identity map pattern - Page 581

Avoiding stack overflows in wrapper DLLs

- by peachykeen

I have a program to which I'm adding fullscreen post-processing effects. I do not have the source for the program (it's proprietary, although a developer did send me a copy of the debug symbols, .map format). I have the code for the effects written and working, no problems. My issue now is linking the two. I've tried two methods so far: Use Detours to modify the original program's import table. This works great and is guaranteed to be stable, but the user's I've talked to aren't comfortable with it, it requires installation (beyond extracting an archive), and there's some question if patching the program with Detours is valid under the terms of the EULA. So, that option is out. The other option is the traditional DLL-replacement. I've wrapped OpenGL (opengl32.dll), and I need the program to load my DLL instead of the system copy (just drop it in the program folder with the right name, that's easy). I then need my DLL to load the Cg framework and runtime (which relies on OpenGL) and a few other things. When Cg loads, it calls some of my functions, which call Cg functions, and I tend to get stack overflows and infinite loops. I need to be able to either include the Cg DLLs in a subdirectory and still use their functions (not sure if it's possible to have my DLLs import table point to a DLL in a subdirectory) or I need to dynamically link them (which I'd rather not do, just to simplify the build process), something to force them to refer to the system's file (not my custom replacement). The entire chain is: Program loads DLL A (named opengl32.dll). DLL A loads Cg.dll and dynamically links (GetProcAddress) to sysdir/opengl32.dll. I now need Cg.dll to also refer to sysdir/opengl32.dll, not DLL A. How would this be done? Edit: How would this be done easily without using GetProcAddress? If nothing else works, I'm willing to fall back to that, but I'd rather not if at all possible. Edit2: I just stumbled across the function SetDllDirectory in the MSDN docs (on a totally unrelated search). At first glance, that looks like what I need. Is that right, or am I misjudging? (off to test it now) Edit3: I've solved this problem by doing thing a bit differently. Instead of dropping an OpenGL32.dll, I've renamed my DLL to DInput.dll. Not only does it have the advantage of having to export one function instead of well over 120 (for the program, Cg, and GLEW), I don't have to worry about functions running back in (I can link to OpenGL as usual). To get into the calls I need to intercept, I'm using Detours. All in all, it works much better. This question, though, is still an interesting problem (and hopefully will be useful for anyone else trying to do crazy things in the future). Both the answers are good, so I'm not sure yet which to pick...

Read the article

Switch activity from a AlertDialog button

- by Fahim Ahmed

Let's say , I have three classes : MapsActivity , MyItemizedOverlay & GetDirectionActivity . In MyItemizedOverlay , I want to switch to GetDirectionActivity after the positive dialog button is clicked . ActiveDialog is placed under onTap method , so that I can get the GeoPoint. For this , what I've done : In ItemizedOverlay class : @Override public boolean onTap(GeoPoint p, MapView mapView) { // TODO Auto-generated method stub int lat = p.getLatitudeE6(); int lot = p.getLongitudeE6(); AlertDialog.Builder dialog = new AlertDialog.Builder(mContext); dialog.setTitle("Confirmation"); dialog.setMessage("Confirm this as end point ?"); dialog.setPositiveButton("Yes", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int arg1) { // TODO Auto-generated method stub Intent intent = new Intent(mContext, GetDestination.class); startActivity(intent); } }); dialog.setNegativeButton("No", null); dialog.show(); return true ; } here IDE shows that I have a error in startActivity(intent) line . I've tried that also : In MyItemizedOverlay class : @Override public boolean onTap(GeoPoint p, MapView mapView) { return super.onTap(p, mapView); } In MapsActivity class : GeoPoint point2 = null ; confirmationOverlay.onTap(point2, mapView) ; int latt = point.getLatitudeE6() ; int longt = point.getLongitudeE6(); final int endpointArray [] = {latt , longt}; if(some condition to show the alert dialog after tapping) { AlertDialog.Builder dialog = new AlertDialog.Builder(MapsActivity.this); dialog.setTitle("Confirmation"); dialog.setMessage("Confirm this location as end point ?"); dialog.setPositiveButton("Yes", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int arg1) { // TODO Auto-generated method stub Intent intent = new Intent(MapsActivity.this,GetDestination.class); intent.putExtra("geopoint" , endpointArray); startActivity(intent); } }); dialog.setNegativeButton("No", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int arg1) { } }); dialog.show(); } For the if statement what sort of condition I can use ? If I set it just like lat0 then the alertdialog appears without tapping on the map. I know this is very silly , but since I am new in both android & java , I hope you guys will consider it. Please help !

Read the article

Inference engine to calculate matching set according to internal rules

- by Zecrates

I have a set of objects with attributes and a bunch of rules that, when applied to the set of objects, provides a subset of those objects. To make this easier to understand I'll provide a concrete example. My objects are persons and each has three attributes: country of origin, gender and age group (all attributes are discrete). I have a bunch of rules, like "all males from the US", which correspond with subsets of this larger set of objects. I'm looking for either an existing Java "inference engine" or something similar, which will be able to map from the rules to a subset of persons, or advice on how to go about creating my own. I have read up on rule engines, but that term seems to be exclusively used for expert systems that externalize the business rules, and usually doesn't include any advanced form of inferencing. Here are some examples of the more complex scenarios I have to deal with: I need the conjunction of rules. So when presented with both "include all males" and "exclude all US persons in the 10 - 20 age group," I'm only interested in the males outside of the US, and the males within the US that are outside the 10 - 20 age group. Rules may have different priorities (explicitly defined). So a rule saying "exclude all males" will override a rule saying "include all US males." Rules may be conflicting. So I could have both an "include all males" and an "exclude all males" in which case the priorities will have to settle the issue. Rules are symmetric. So "include all males" is equivalent to "exclude all females." Rules (or rather subsets) may have meta rules (explicitly defined) associated with them. These meta rules will have to be applied in any case that the original rule is applied, or if the subset is reached via inferencing. So if a meta rule of "exclude the US" is attached to the rule "include all males", and I provide the engine with the rule "exclude all females," it should be able to inference that the "exclude all females" subset is equivalent to the "include all males" subset and as such apply the "exclude the US" rule additionally. I can in all likelihood live without item 5, but I do need all the other properties mentioned. Both my rules and objects are stored in a database and may be updated at any stage, so I'd need to instantiate the 'inference engine' when needed and destroy it afterward.

Read the article

retrieving information from web service calls

- by Monte Chan

Hi all, I am trying to retrieve information from a web service call. The following is what I have so far. In my text view, it is showing Map {item=anyType{key=TestKey; value=2;}; item=anyType{key=TestField; value=adsfasd; };} When I ran that in the debugger, I can see the information above in the variable, tempvar. But the question is, how do I retrieve the information (i.e. the actual values of "key" and "value" in each of the array positions)? Yes, I know there is a lot going on in onCreate and I will fix it later. Thanks in advance, Monte My codes are as follows, import java.util.Vector; import android.app.Activity; import android.os.Bundle; import android.widget.TextView; import org.ksoap2.SoapEnvelope; import org.ksoap2.serialization.SoapObject; import org.ksoap2.serialization.SoapSerializationEnvelope; import org.ksoap2.transport.AndroidHttpTransport; public class ViewHitUpActivity extends Activity { private static final String SOAP_ACTION = "test_function"; private static final String METHOD_NAME = "test_function"; private static final String NAMESPACE = "http://www.monteandjanicechan.com/"; private static final String URL = "http://www.monteandjanicechan.com/ws/test_ws.cfc?wsdl"; // private Object resultRequestSOAP = null; private TextView tv; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); SoapObject request = new SoapObject(NAMESPACE, METHOD_NAME); tv = (TextView)findViewById(R.id.people_view); //SoapObject request.addProperty("test_item", "1"); SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11); envelope.setOutputSoapObject(request); AndroidHttpTransport androidHttpTransport = new AndroidHttpTransport(URL); try { androidHttpTransport.call(SOAP_ACTION, envelope); /* resultRequestSOAP = envelope.getResponse(); Vector tempResult = (Vector) resultRequestSOAP("test_functionReturn"); */ SoapObject resultsRequestSOAP = (SoapObject) envelope.bodyIn; Vector tempResult = (Vector) resultsRequestSOAP.getProperty("test_functionReturn"); int testsize = tempResult.size(); // SoapObject test = (SoapObject) tempResult.get(0); //String[] results = (String[]) resultRequestSOAP; Object tempvar = tempResult.elementAt(1); tv.setText(tempvar.toString()); } catch (Exception aE) { aE.printStackTrace (); tv.setText(aE.getClass().getName() + ": " + aE.getMessage()); } } }

Read the article

How do I create a list or set object in a class in Python?

- by Az

For my project, the role of the Lecturer (defined as a class) is to offer projects to students. Project itself is also a class. I have some global dictionaries, keyed by the unique numeric id's for lecturers and projects that map to objects. Thus for the "lecturers" dictionary (currently): lecturer[id] = Lecturer(lec_name, lec_id, max_students) I'm currently reading in a white-space delimited text file that has been generated from a database. I have no direct access to the database so I haven't much say on how the file is formatted. Here's a fictionalised snippet that shows how the text file is structured. Please pardon the cheesiness. 0001 001 "Miyamoto, S." "Even Newer Super Mario Bros" 0002 001 "Miyamoto, S." "Legend of Zelda: Skies of Hyrule" 0003 002 "Molyneux, P." "Project Milo" 0004 002 "Molyneux, P." "Fable III" 0005 003 "Blow, J." "Ponytail" The structure of each line is basically proj_id, lec_id, lec_name, proj_name. Now, I'm currently reading the relevant data into the relevant objects. Thus, proj_id is stored in class Project whereas lec_name is a class Lecturer object, et al. The Lecturer and Project classes are not currently related. However, as I read in each line from the text file, for that line, I wish to read in the project offered by the lecturer into the Lecturer class; I'm already reading the proj_id into the Project class. I'd like to create an object in Lecturer called offered_proj which should be a set or list of the projects offered by that lecturer. Thus whenever, for a line, I read in a new project under the same lec_id, offered_proj will be updated with that project. If I wanted to get display a list of projects offered by a lecturer I'd ideally just want to use print lecturers[lec_id].offered_proj. My Python isn't great and I'd appreciate it if someone could show me a way to do that. I'm not sure if it's better as a set or a list, as well. Update After the advice from Alex Martelli and Oddthinking I went back and made some changes and tried to print the results. Here's the code snippet: for line in csv_file: proj_id = int(line[0]) lec_id = int(line[1]) lec_name = line[2] proj_name = line[3] projects[proj_id] = Project(proj_id, proj_name) lecturers[lec_id] = Lecturer(lec_id, lec_name) if lec_id in lecturers.keys(): lecturers[lec_id].offered_proj.add(proj_id) print lec_id, lecturers[lec_id].offered_proj The print lecturers[lec_id].offered_proj line prints the following output: 001 set([0001]) 001 set([0002]) 002 set([0003]) 002 set([0004]) 003 set([0005]) It basically feels like the set is being over-written or somesuch. So if I try to print for a specific lecturer print lec_id, lecturers[001].offered_proj all I get is the last the proj_id that has been read in.

Read the article

Use QuickCheck by generating primes

- by Dan

Background For fun, I'm trying to write a property for quick-check that can test the basic idea behind cryptography with RSA. Choose two distinct primes, p and q. Let N = p*q e is some number relatively prime to (p-1)(q-1) (in practice, e is usually 3 for fast encoding) d is the modular inverse of e modulo (p-1)(q-1) For all x such that 1 < x < N, it is always true that (x^e)^d = x modulo N In other words, x is the "message", raising it to the eth power mod N is the act of "encoding" the message, and raising the encoded message to the dth power mod N is the act of "decoding" it. (The property is also trivially true for x = 1, a case which is its own encryption) Code Here are the methods I have coded up so far: import Test.QuickCheck -- modular exponentiation modExp :: Integral a => a -> a -> a -> a modExp y z n = modExp' (y `mod` n) z `mod` n where modExp' y z | z == 0 = 1 | even z = modExp (y*y) (z `div` 2) n | odd z = (modExp (y*y) (z `div` 2) n) * y -- relatively prime rPrime :: Integral a => a -> a -> Bool rPrime a b = gcd a b == 1 -- multiplicative inverse (modular) mInverse :: Integral a => a -> a -> a mInverse 1 _ = 1 mInverse x y = (n * y + 1) `div` x where n = x - mInverse (y `mod` x) x -- just a quick way to test for primality n `divides` x = x `mod` n == 0 primes = 2:filter isPrime [3..] isPrime x = null . filter (`divides` x) $ takeWhile (\y -> y*y <= x) primes -- the property prop_rsa (p,q,x) = isPrime p && isPrime q && p /= q && x > 1 && x < n && rPrime e t ==> x == (x `powModN` e) `powModN` d where e = 3 n = p*q t = (p-1)*(q-1) d = mInverse e t a `powModN` b = modExp a b n (Thanks, google and random blog, for the implementation of modular multiplicative inverse) Question The problem should be obvious: there are way too many conditions on the property to make it at all usable. Trying to invoke quickCheck prop_rsa in ghci made my terminal hang. So I've poked around the QuickCheck manual a bit, and it says: Properties may take the form forAll <generator> $ \<pattern> -> <property> How do I make a <generator> for prime numbers? Or with the other constraints, so that quickCheck doesn't have to sift through a bunch of failed conditions? Any other general advice (especially regarding QuickCheck) is welcome.

Read the article

Problem accessing updated variables within OnTouch

- by Jay Smith

I have an OnTouch and a setOnTouchListener that updates varibles which contain screen coord info. The problem is it doesnt seem to ever update them. On line 78, RGB.setText(test); it never changes from 0.0. If i were to move that line and the line above it into the onTouch it updates. any idea what is wrong? Thank you. package com.evankimia.huskybus; import com.test.huskybus.R; import android.app.Activity; import android.os.Bundle; import android.view.MotionEvent; import android.view.View; import android.view.View.OnTouchListener; import android.widget.TextView; public class HuskyBus extends Activity { TextView RGB; private CampusMap mCampusMap; private float startX = 0; //track x from one ACTION_MOVE to the next private float startY = 0; //track y from one ACTION_MOVE to the next float scrollByX = 0; //x amount to scroll by float scrollByY = 0; //y amount to scroll by /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); RGB = (TextView) findViewById(R.id.coordBox); mCampusMap = (CampusMap) findViewById(R.id.map); mCampusMap.setOnTouchListener(new OnTouchListener() { @Override public boolean onTouch(View v, MotionEvent event) { // TODO Auto-generated method stub switch (event.getAction()) { case MotionEvent.ACTION_DOWN: // Remember our initial down event location. startX = event.getRawX(); startY = event.getRawY(); break; case MotionEvent.ACTION_MOVE: float x = event.getRawX(); float y = event.getRawY(); // Calculate move update. This will happen many times // during the course of a single movement gesture. scrollByX = x - startX; //move update x increment scrollByY = y - startY; //move update y increment startX = x; //reset initial values to latest startY = y; mCampusMap.invalidate(); break; }//end switch return false; } ; }); //end onDraw? String test = "" + scrollByX; RGB.setText(test); } }

Read the article

Function signature-like expressions as C++ template arguments

- by Jeff Lee

I was looking at Don Clugston's FastDelegate mini-library and noticed a weird syntactical trick with the following structure: TemplateClass< void( int, int ) > Object; It almost appears as if a function signature is being used as an argument to a template instance declaration. This technique (whose presence in FastDelegate is apparently due to one Jody Hagins) was used to simplify the declaration of template instances with a semi-arbitrary number of template parameters. To wit, it allowed this something like the following: // A template with one parameter template<typename _T1> struct Object1 { _T1 m_member1; }; // A template with two parameters template<typename _T1, typename _T2> struct Object2 { _T1 m_member1; _T2 m_member2; }; // A forward declaration template<typename _Signature> struct Object; // Some derived types using "function signature"-style template parameters template<typename _Dummy, typename _T1> struct Object<_Dummy(_T1)> : public Object1<_T1> {}; template<typename _Dummy, typename _T1, typename _T2> struct Object<_Dummy(_T1, _T2)> : public Object2<_T1, _T2> {}; // A. "Vanilla" object declarations Object1<int> IntObjectA; Object2<int, char> IntCharObjectA; // B. Nifty, but equivalent, object declarations typedef void UnusedType; Object< UnusedType(int) > IntObjectB; Object< UnusedType(int, char) > IntCharObjectB; // C. Even niftier, and still equivalent, object declarations #define DeclareObject( ... ) Object< UnusedType( __VA_ARGS__ ) > DeclareObject( int ) IntObjectC; DeclareObject( int, char ) IntCharObjectC; Despite the real whiff of hackiness, I find this kind of spoofy emulation of variadic template arguments to be pretty mind-blowing. The real meat of this trick seems to be the fact that I can pass textual constructs like "Type1(Type2, Type3)" as arguments to templates. So here are my questions: How exactly does the compiler interpret this construct? Is it a function signature? Or, is it just a text pattern with parentheses in it? If the former, then does this imply that any arbitrary function signature is a valid type as far as the template processor is concerned? A follow-up question would be that since the above code sample is valid code, why doesn't the C++ standard just allow you to do something like the following, which is does not compile? template<typename _T1> struct Object { _T1 m_member1; }; // Note the class identifier is also "Object" template<typename _T1, typename _T2> struct Object { _T1 m_member1; _T2 m_member2; }; Object<int> IntObject; Object<int, char> IntCharObject;

Read the article

How can I structure my MustacheJS template to add dynamic classes based on the values from a JSON file?

- by JGallardo

OBJECTIVE To build an app that allows the user to search for locations. CURRENT STATE At the moment the locations listed are few, so they are just all presented when landing on the "dealers" page. BACKGROUND Previously there were only about 50 showrooms carrying a product we sell, so a static HTML page was fine. And displays as But the page size grew to about 1500 lines of code after doing this. We have gotten more and need a scalable solution so that we can add many more dealers fast. In other projects, I have previously used MustacheJS and to load in values from a JSON file. I know the ideally this will be an AJAX application. Perhaps I might be better off with database here? Below is what I have in mind so far, and it "works" up to a certain point, but seems not to be anywhere near the most sustainable solution that can be efficiently scaled. HTML <a id="{{state}}"></a> <div> <h4>{{dealer}} : {{city}}, {{state}} {{l_type}}</h4> <div class="{{icon_class}}"> <ul> <li><i class="icon-map-marker"></i></li> <li><i class="icon-phone"></i></li> <li><i class="icon-print"></i></li> </ul> </div> <div class="listingInfo"> <p>{{street}} <br>{{suite}}<br> {{city}}, {{state}} {{zip}}<br> Phone: {{phone}}<br> {{toll_free}}<br> {{fax}} </p> </div> </div> <hr> JSON { "dealers" : [ { "dealer":"Benco Dental", "City":"Denver", "state":"CO", "zip":"80112", "l_type":"Showroom", "icon_class":"listingIcons_3la", "phone":"(303) 790-1421", "toll_free":null, "fax":"(303) 790-1421" }, { "dealer":"Burkhardt Dental Supply", "City":"Portland", "state":"OR", "zip":"97220", "l_type":"Showroom", "icon_class":"listingIcons", "phone":" (503) 252-9777", "toll_free":"(800) 367-3030", "fax":"(866) 408-3488" } ]} CHALLENGES The CSS class wrapping the ul will vary based on how many fields there are. In this case there are 3, so the class is "listingIcons_3la" The "toll free" number section should only show up if in fact, there is a toll free number. the fax number should only show up if there is a value for a fax number.

Read the article

A shortest path problem with superheroes and intergalactic journeys

- by Dman

You are a super-hero in the year 2222 and you are faced with this great challenge: starting from your home planet Ilop you must try to reach Acinhet or else your planet will be destroyed by evil green little monsters. To do this you are given a map of the universe: there are N planets and M inter-planetary connections ( bidirectional ) that bind these planets. Each connection requires a certain time and a certain amount of fuel in order for you to cover the connection from one planet to another. The total time spent going from one planet to another is obtained by multiplying the time past to cover each connection between all the planets you go through. There are some "key planets", that allow you to refuel if you arrive on those certain "key planets". A "key planet" is the planet with the property that if it disappears the road between at least two planets would be lost.(In the example posted below with the input/output files such a "key planet" is 2 because without it the road to 7 would be lost) When you start your mission you are given the possibility of choosing between K ships each with its own maximum fuel capacity. The goal is to find the SHORTEST TIME CONSUMING path but also choose the ship with the minimum fuel capacity that can cover that shortest path(this means that if more ships can cover the shortest path you choose the one with the minimum fuel capacity). Because the minimum time can be a rather large number (over long long int) you are asked to provide only the last 6 digits of the number. For a better understanding of the task, here is an example of input/output files: INPUT: mission.in 7 8 6 1 4 6 5 9 8 7 10 1 2 7 8 1 4 14 9 1 5 3 1 2 3 1 2 2 7 7 1 3 4 2 2 4 6 4 1 5 6 3 7 On the first line (in order): N M K On the second line :the number for the starting planet and the finishing planet On the third line :K numbers that represent the capacities of the ships you can choose from Then you have M lines, all of them have the same structure: Xi Yi Ti Fi-which means that there is a connection between Xi and Yi and you can cover the distance from Xi to Yi in Ti time and with a Fi fuel consumption. OUTPUT:mission.out 000014 8 1 2 3 4 On the first line:the minimum time and fuel consumption; On the second line :the path Restrictions: 2 = N = 1 000 1 = M = 30 000 1 = K = 10 000 Any suggestions or ideas of how this problem might be solved would be most welcomed.

Read the article

How do I destruct data associated with an object after the object no longer exists?

- by Phineas

I'm creating a class (say, C) that associates data (say, D) with an object (say, O). When O is destructed, O will notify C that it soon will no longer exist :( ... Later, when C feels it is the right time, C will let go of what belonged to O, namely D. If D can be any type of object, what's the best way for C to be able to execute "delete D;"? And what if D is an array of objects? My solution is to have D derive from a base class that C has knowledge of. When the time comes, C calls delete on a pointer to the base class. I've also considered storing void pointers and calling delete, but I found out that's undefined behavior and doesn't call D's destructor. I considered that templates could be a novel solution, but I couldn't work that idea out. Here's what I have so far for C, minus some details: // This class is C in the above description. There may be many instances of C. class Context { public: // D will inherit from this class class Data { public: virtual ~Data() {} }; Context(); ~Context(); // Associates an owner (O) with its data (D) void add(const void* owner, Data* data); // O calls this when he knows its the end (O's destructor). // All instances of C are now aware that O is gone and its time to get rid // of all associated instances of D. static void purge (const void* owner); // This is called periodically in the application. It checks whether // O has called purge, and calls "delete D;" void refresh(); // Side note: sometimes O needs access to D Data *get (const void *owner); private: // Used for mapping owners (O) to data (D) std::map _data; }; // Here's an example of O class Mesh { public: ~Mesh() { Context::purge(this); } void init(Context& c) const { Data* data = new Data; // GL initialization here c.add(this, new Data); } void render(Context& c) const { Data* data = c.get(this); } private: // And here's an example of D struct Data : public Context::Data { ~Data() { glDeleteBuffers(1, &vbo); glDeleteTextures(1, &texture); } GLint vbo; GLint texture; }; }; P.S. If you're familiar with computer graphics and VR, I'm creating a class that separates an object's per-context data (e.g. OpenGL VBO IDs) from its per-application data (e.g. an array of vertices) and frees the per-context data at the appropriate time (when the matching rendering context is current).

Read the article

Hibernate can't load Custom SQL collection

- by Geln Yang

Hi, There is a table Item like, code,name 01,parent1 02,parent2 0101,child11 0102,child12 0201,child21 0202,child22 Create a java object and hbm xml to map the table.The Item.parent is a Item whose code is equal to the first two characters of its code : class Item{ String code; String name; Item parent; List<Item> children; .... setter/getter.... } <hibernate-mapping> <class name="Item" table="Item"> <id name="code" length="4" type="string"> <generator class="assigned" /> </id> <property name="name" column="name" length="50" not-null="true" /> <many-to-one name="parent" class="Item" not-found="ignore"> <formula> <![CDATA[ (select i.code,r.name from Item i where (case length(code) when 4 then i.code=SUBSTRING(code,1,2) else false end)) ]]> </formula> </many-to-one> <bag name="children"></bag> </class> </hibernate-mapping> I try to use formula to define the many-to-one relationship,but it doesn't work!Is there something wrong?Or is there other method? Thanks! ps,I use mysql database. add 2010/05/23 Pascal's answer is right,but the "false" value must be replaced with other expression,like "1=2".Because the "false" value would be considered to be a column of the table. select i.code from Item i where ( case length(code) when 4 then i.code=SUBSTRING(code,1,2) else 1=2 end) And I have another question about the children "bag" mapping.There isn't formula configuration option for "bag",but we can use "loader" to load a sql-query.I configure the "bag" as following.But it get a list whose size is 0.What's wrong with it? <class> ... ... <bag name="children"> <key /> <one-to-many class="Item"></one-to-many> <loader query-ref="getChildren"></loader> </bag> </class> <sql-query name="getChildren"> <load-collection alias="r" role="Item.children" /> <![CDATA[(select {r.*} from Item r join Item o where o.code=:code and ( case length(o.code) when 2 then (length(r.code)=4 and SUBSTRING(r.code,1,2)=o.code) else 1=2 end ))]]> </sql-query>

Read the article

Need help configurating my Tomcat server

- by gablin

I just reinstalled my entire server, and now I can't seem to get my JSP-based website to work on Tomcat anymore. I use the same server.xml file, which worked perfectly before the reinstallation, but no longer. Here's the content of the server.xml file which worked before:  <Listener className="org.apache.catalina.core.AprLifecycleListener" SSLEngine="on" />  <Listener className="org.apache.catalina.core.JasperListener" />  <Listener className="org.apache.catalina.mbeans.ServerLifecycleListener" /> <Listener className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener" />  <GlobalNamingResources>  <Resource name="UserDatabase" auth="Container" type="org.apache.catalina.UserDatabase" description="User database that can be updated and saved" factory="org.apache.catalina.users.MemoryUserDatabaseFactory" pathname="conf/tomcat-users.xml" /> </GlobalNamingResources>  <Service name="Catalina">    <Connector port="8080" protocol="HTTP/1.1" connectionTimeout="20000" redirectPort="8443" />      <Connector port="8009" protocol="AJP/1.3" redirectPort="8443" />   <Engine name="Catalina" defaultHost="localhost">      <Realm className="org.apache.catalina.realm.UserDatabaseRealm" resourceName="UserDatabase"/>        <Host name="www.rebootradio.nu"> <Alias>rebootradio.nu</Alias> <Context path="" docBase="D:/services/http/rebootradio.nu" debug="1" reloadable="true"/> </Host> </Engine> </Service> </Server> The JSP site doesn't use any WAR files or anything like that; there's just a default.jsp in the specified folder D:/services/http/rebootradio.nu which loads the site. As I said, this configuration worked before, but now with the latest verion of XAMPP and Tomcat it doesn't work anymore. All I get is a 404 message saying The requested resource () is not available.

Read the article

Rails. Putting update logic in your migrations

- by Daniel Abrahamsson

A couple of times I've been in the situation where I've wanted to refactor the design of some model and have ended up putting update logic in migrations. However, as far as I've understood, this is not good practice (especially since you are encouraged to use your schema file for deployment, and not your migrations). How do you deal with these kind of problems? To clearify what I mean, say I have a User model. Since I thought there would only be two kinds of users, namely a "normal" user and an administrator, I chose to use a simple boolean field telling whether the user was an adminstrator or not. However, after I while I figured I needed some third kind of user, perhaps a moderator or something similar. In this case I add a UserType model (and the corresponding migration), and a second migration for removing the "admin" flag from the user table. And here comes the problem. In the "add_user_type_to_users" migration I have to map the admin flag value to a user type. Additionally, in order to do this, the user types have to exist, meaning I can not use the seeds file, but rather create the user types in the migration (also considered bad practice). Here comes some fictional code representing the situation: class CreateUserTypes < ActiveRecord::Migration def self.up create_table :user_types do |t| t.string :name, :nil => false, :unique => true end #Create basic types (can not put in seed, because of future migration dependency) UserType.create!(:name => "BASIC") UserType.create!(:name => "MODERATOR") UserType.create!(:name => "ADMINISTRATOR") end def self.down drop_table :user_types end end class AddTypeIdToUsers < ActiveRecord::Migration def self.up add_column :users, :type_id, :integer #Determine type via the admin flag basic = UserType.find_by_name("BASIC") admin = UserType.find_by_name("ADMINISTRATOR") User.all.each {|u| u.update_attribute(:type_id, (u.admin?) ? admin.id : basic.id)} #Remove the admin flag remove_column :users, :admin #Add foreign key execute "alter table users add constraint fk_user_type_id foreign key (type_id) references user_types (id)" end def self.down #Re-add the admin flag add_column :users, :admin, :boolean, :default => false #Reset the admin flag (this is the problematic update code) admin = UserType.find_by_name("ADMINISTRATOR") execute "update users set admin=true where type_id=#{admin.id}" #Remove foreign key constraint execute "alter table users drop foreign key fk_user_type_id" #Drop the type_id column remove_column :users, :type_id end end As you can see there are two problematic parts. First the row creation part in the first model, which is necessary if I would like to run all migrations in a row, then the "update" part in the second migration that maps the "admin" column to the "type_id" column. Any advice?

Read the article

Pointers to Derived Class Objects Losing vfptr

- by duckworthd

To begin, I am trying to write a run-of-the-mill, simple Ray Tracer. In my Ray Tracer, I have multiple types of geometries in the world, all derived from a base class called "SceneObject". I've included the header for it here. /** Interface for all objects that will appear in a scene */ class SceneObject { public: mat4 M, M_inv; Color c; SceneObject(); ~SceneObject(); /** The transformation matrix to be applied to all points of this object. Identity leaves the object in world frame. */ void setMatrix(mat4 M); void setMatrix(MatrixStack mStack); void getMatrix(mat4& M); /** The color of the object */ void setColor(Color c); void getColor(Color& c); /** Alter one portion of the color, leaving the rest as they were. */ void setDiffuse(vec3 rgb); void setSpecular(vec3 rgb); void setEmission(vec3 rgb); void setAmbient(vec3 rgb); void setShininess(double s); /** Fills 'inter' with information regarding an intersection between this object and 'ray'. Ray should be in world frame. */ virtual void intersect(Intersection& inter, Ray ray) = 0; /** Returns a copy of this SceneObject */ virtual SceneObject* clone() = 0; /** Print information regarding this SceneObject for debugging */ virtual void print() = 0; }; As you can see, I've included a couple virtual functions to be implemented elsewhere. In this case, I have only two derived class -- Sphere and Triangle, both of which implement the missing member functions. Finally, I have a Parser class, which is full of static methods that do the actual "Ray Tracing" part. Here's a couple snippets for relevant portions void Parser::trace(Camera cam, Scene scene, string outputFile, int maxDepth) { int width = cam.getNumXPixels(); int height = cam.getNumYPixels(); vector<vector<vec3>> colors; colors.clear(); for (int i = 0; i< width; i++) { vector<vec3> ys; for (int j = 0; j<height; j++) { Intersection intrsct; Ray ray; cam.getRay(ray, i, j); vec3 color; printf("Obtaining color for Ray[%d,%d]\n", i,j); getColor(color, scene, ray, maxDepth); ys.push_back(color); } colors.push_back(ys); } printImage(colors, width, height, outputFile); } void Parser::getColor(vec3& color, Scene scene, Ray ray, int numBounces) { Intersection inter; scene.intersect(inter,ray); if(inter.isIntersecting()){ Color c; inter.getColor(c); c.getAmbient(color); } else { color = vec3(0,0,0); } } Right now, I've forgone the true Ray Tracing part and instead simply return the color of the first object hit, if any. As you have no doubt noticed, the only way the computer knows that a ray has intersected an object is through Scene.intersect(), which I also include. void Scene::intersect(Intersection& i, Ray r) { Intersection result; result.setDistance(numeric_limits<double>::infinity()); result.setIsIntersecting(false); double oldDist; result.getDistance(oldDist); /* Cycle through all objects, making result the closest one */ for(int ind=0; ind<objects.size(); ind++){ SceneObject* thisObj = objects[ind]; Intersection betterIntersect; thisObj->intersect(betterIntersect, r); double newDist; betterIntersect.getDistance(newDist); if (newDist < oldDist){ result = betterIntersect; oldDist = newDist; } } i = result; } Alright, now for the problem. I begin by creating a scene and filling it with objects outside of the Parser::trace() method. Now for some odd reason, I cast Ray for i=j=0 and everything works wonderfully. However, by the time the second ray is cast all of the objects stored in my Scene no longer recognize their vfptr's! I stepped through the code with a debugger and found that the information to all the vfptr's are lost somewhere between the end of getColor() and the continuation of the loop. However, if I change the arguments of getColor() to use a Scene& instead of a Scene, then no loss occurs. What crazy voodoo is this?

Read the article

Rails: How do I unserialize from database?

- by Macint

Hello, I am currently trying to save information for an invoice/bill. On the invoice I want to show what the total price is made up of. The procedures & items, their price and the qty. So in the end I hope to get it to look like this: Consult [date] [total_price] Procedure_name [price] [qty] Procedure_name [price] [qty] Consult [date] [total_price] Procedure_name [price] [qty] etc... All this information is available through the database but i want to save the information as a separate copy. That way if the user changes the price of some procedures the invoice information is still correct. I thought i'd do this by serializing and save the data to a column (consult_data) in the Invoice table. My Model: class Invoice < ActiveRecord::Base ...stuff... serialize :consult_data ... end This is what I get from the form (1 consult and 3 procedures): {"commit"=>"Save draft", "authenticity_token"=>"MZ1OiOCtj/BOu73eVVkolZBWoN8Fy1skHqKgih7Sbzw=", "id"=>"113", "consults"=>[{"consult_date"=>"2010-02-20", "consult_problem"=>"ABC", "procedures"=>[{"name"=>"asdasdasd", "price"=>"2.0", "qty"=>"1"}, {"name"=>"AAAnd another one", "price"=>"45.0", "qty"=>"4"}, {"name"=>"asdasdasd", "price"=>"2.0", "qty"=>"1"}], "consult_id"=>"1"}]} My save action: def add_to_invoice @invoice = @current_practice.invoices.find_by_id(params[:id]) @invoice.consult_data=params[:consults] if @invoice.save render :text => "I think it worked" else render :text => "I don't think it worked'" end end It does save to the database and if I look at the entry in the console I can see that it is all there: consult_data: "--- \n- !map:HashWithIndifferentAccess \n consult_da..." (---The question---) But I can't seam to get back my data. I tried defining a variable to the consult_data attribute and then doing "variable.consult_problem" or "variable[:consult_problem]" (also tried looping) but it only throws no-method-errors back at me. How do I unserialize the data from the database and turn it back into hash that i can use? Thank you very much for any help!

Read the article

Server Error in '/' Application (ASP.NET)

- by baeltazor

Hi All I just setup up member ship roles and registration on my website with visual web developer using the tutorial on msdn. It works perfectly locally, but when i uploaded it to my server, I get the following page: "Server Error in '/' Application. -------------------------------------------------------------------------------- Configuration Error Description: An error occurred during the processing of a configuration file required to service this request. Please review the specific error details below and modify your configuration file appropriately. Parser Error Message: The connection name 'LocalSqlServer' was not found in the applications configuration or the connection string is empty. Source Error: [No relevant source lines] Source File: machine.config Line: 160 -------------------------------------------------------------------------------- Version Information: Microsoft .NET Framework Version:2.0.50727.4200; ASP.NET Version:2.0.50727.4016 " Does anybody know why I'm seeing this and how I may go about fixinf this? Any help is greatly appreciated. Thank you Bael. EDIT: I have just looked at my web.config file after reading the following line in the error message: "The connection name 'LocalSqlServer' was not found in the applications configuration or the connection string is empty." ... And have noticed that the following element is completely empty: <connectionStrings/> // Is this one supposed to be empty? if not what should go here? In the error it implies it shouldn't be empty. Also, I don't know where I should place LocalSqlServer LATEST EDIT After changing DataSource to LocalHost i get the following error: Server Error in '/JTS' Application. -------------------------------------------------------------------------------- A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server) Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.Data.SqlClient.SqlException: A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server) Source Error: An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below. Stack Trace: [SqlException (0x80131904): A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)] System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) +4849015 System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj) +194 System.Data.SqlClient.TdsParser.Connect(ServerInfo serverInfo, SqlInternalConnectionTds connHandler, Boolean ignoreSniOpenTimeout, Int64 timerExpire, Boolean encrypt, Boolean trustServerCert, Boolean integratedSecurity, SqlConnection owningObject) +4862333 System.Data.SqlClient.SqlInternalConnectionTds.AttemptOneLogin(ServerInfo serverInfo, String newPassword, Boolean ignoreSniOpenTimeout, Int64 timerExpire, SqlConnection owningObject) +90 System.Data.SqlClient.SqlInternalConnectionTds.LoginNoFailover(String host, String newPassword, Boolean redirectedUserInstance, SqlConnection owningObject, SqlConnectionString connectionOptions, Int64 timerStart) +342 System.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(SqlConnection owningObject, SqlConnectionString connectionOptions, String newPassword, Boolean redirectedUserInstance) +221 System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, Object providerInfo, String newPassword, SqlConnection owningObject, Boolean redirectedUserInstance) +189 System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection) +185 System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnection owningConnection, DbConnectionPool pool, DbConnectionOptions options) +31 System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject) +433 System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject) +66 System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject) +499 System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection) +65 System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +117 System.Data.SqlClient.SqlConnection.Open() +122 System.Web.DataAccess.SqlConnectionHolder.Open(HttpContext context, Boolean revertImpersonate) +87 System.Web.DataAccess.SqlConnectionHelper.GetConnection(String connectionString, Boolean revertImpersonation) +221 System.Web.Security.SqlMembershipProvider.GetPasswordWithFormat(String username, Boolean updateLastLoginActivityDate, Int32& status, String& password, Int32& passwordFormat, String& passwordSalt, Int32& failedPasswordAttemptCount, Int32& failedPasswordAnswerAttemptCount, Boolean& isApproved, DateTime& lastLoginDate, DateTime& lastActivityDate) +815 System.Web.Security.SqlMembershipProvider.CheckPassword(String username, String password, Boolean updateLastLoginActivityDate, Boolean failIfNotApproved, String& salt, Int32& passwordFormat) +105 System.Web.Security.SqlMembershipProvider.CheckPassword(String username, String password, Boolean updateLastLoginActivityDate, Boolean failIfNotApproved) +42 System.Web.Security.SqlMembershipProvider.ValidateUser(String username, String password) +78 System.Web.UI.WebControls.Login.AuthenticateUsingMembershipProvider(AuthenticateEventArgs e) +60 System.Web.UI.WebControls.Login.OnAuthenticate(AuthenticateEventArgs e) +119 System.Web.UI.WebControls.Login.AttemptLogin() +115 System.Web.UI.WebControls.Login.OnBubbleEvent(Object source, EventArgs e) +101 System.Web.UI.Control.RaiseBubbleEvent(Object source, EventArgs args) +37 System.Web.UI.WebControls.Button.OnCommand(CommandEventArgs e) +118 System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +166 System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +10 System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13 System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +36 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1565 -------------------------------------------------------------------------------- Version Information: Microsoft .NET Framework Version:2.0.50727.4927; ASP.NET Version:2.0.50727.4927

Read the article

Do you know why introducing jquery ui autocomplete for my dropdown boxes is also changing my listbox

- by oo

I am trying to change my comboboxes to use autocomplete so i leverage the code listed here (which worked perfectly for my dropdowns) The issue is that i also on the same page have a listbox with the following code: <%= Html.ListBox("Cars", Model.BodyParts.Select( x => new SelectListItem { Text = x.Name, Value = x.Id, Selected = Model.CarsSelected.Any(y => y.Id == x.Id) } ))%> and it appears that the jquery ui code is changing this to a autocomplete dropdown as well (as opposed to keeping it as a multi select list box) any idea how to prevent this from happening? i literally am just using the exact code on this page <script type="text/javascript"> (function($) { $.widget("ui.combobox", { _create: function() { var self = this; var select = this.element.hide(); var input = $("<input>") .insertAfter(select) .autocomplete({ source: function(request, response) { var matcher = new RegExp(request.term, "i"); response(select.children("option").map(function() { var text = $(this).text(); if (!request.term || matcher.test(text)) return { id: $(this).val(), label: text.replace(new RegExp("(?![^&;]+;)(?!<[^<>]*)(" + request.term.replace(/([\^\$\[\]\{\}\*\.\+\?\|\\])/gi, "\\$1") + ")(?![^<>]*>)(?![^&;]+;)", "gi"), "<strong>$1</strong>"), value: text }; })); }, delay: 0, select: function(e, ui) { if (!ui.item) { // remove invalid value, as it didn't match anything $(this).val(""); return false; } $(this).focus(); select.val(ui.item.id); self._trigger("selected", null, { item: select.find("[value='" + ui.item.id + "']") }); }, minLength: 0 }) .addClass("ui-widget ui-widget-content ui-corner-left"); $("<button> </button>") .insertAfter(input) .button({ icons: { primary: "ui-icon-triangle-1-s" }, text: false }).removeClass("ui-corner-all") .addClass("ui-corner-right ui-button-icon") .position({ my: "left center", at: "right center", of: input, offset: "-1 0" }).css("top", "") .click(function() { // close if already visible if (input.autocomplete("widget").is(":visible")) { input.autocomplete("close"); return; } // pass empty string as value to search for, displaying all results input.autocomplete("search", ""); input.focus(); }); } }); })(jQuery); $(function() { $("select").combobox(); }); </script>

Read the article

Strange results - I obtain same value for all keys

- by Pietro Luciani

I have a problem with mapreduce. Giving as input a list of song ("Songname"#"UserID"#"boolean") i must have as result a song list in which is specified how many time different useres listen them... so a output ("Songname","timelistening"). I used hashtable to allow only one couple . With short files it works well but when I put as input a list about 1000000 of records it returns me the same value (20) for all records. This is my mapper: public static class CanzoniMapper extends Mapper<Object, Text, Text, IntWritable>{ private IntWritable userID = new IntWritable(0); private Text song = new Text(); public void map(Object key, Text value, Context context) throws IOException, InterruptedException { /*StringTokenizer itr = new StringTokenizer(value.toString()); while (itr.hasMoreTokens()) { word.set(itr.nextToken()); context.write(word, one); }*/ String[] caratteri = value.toString().split("#"); if(caratteri[2].equals("1")){ song.set(caratteri[0]); userID.set(Integer.parseInt(caratteri[1])); context.write(song,userID); } } } This is my reducer: public static class CanzoniReducer extends Reducer<Text,IntWritable,Text,IntWritable> { private IntWritable result = new IntWritable(); public void reduce(Text key, Iterable<IntWritable> values, Context context) throws IOException, InterruptedException { Hashtable<IntWritable,Text> doppioni = new Hashtable<IntWritable,Text>(); for (IntWritable val : values) { doppioni.put(val,key); } result.set(doppioni.size()); //doppioni.clear(); context.write(key,result); } } and main: Configuration conf = new Configuration(); Job job = new Job(conf, "word count"); job.setJarByClass(Canzoni.class); job.setMapperClass(CanzoniMapper.class); //job.setCombinerClass(CanzoniReducer.class); //job.setNumReduceTasks(2); job.setReducerClass(CanzoniReducer.class); job.setOutputKeyClass(Text.class); job.setOutputValueClass(IntWritable.class); FileInputFormat.addInputPath(job, new Path(args[0])); FileOutputFormat.setOutputPath(job, new Path(args[1])); System.exit(job.waitForCompletion(true) ? 0 : 1); Any idea???

Read the article

How to store date into Mysql database with play framework in scala?

- by Rahul Kulhari

I am working with play framework with scala and what am i doing : login page to login into web app sign up page to register into web app after login i want to store all databases values to user what i want to do: when user register for web app then i want to store user values into database with current time and date but my form is giving error. error: List(FormError(dates,error.required,List())),None) controllers/Application.scala object Application extends Controller { val ta:Form[Keyword] = Form( mapping( "id" -> ignored(NotAssigned:Pk[Long]), "word" -> nonEmptyText, "blog" -> nonEmptyText, "cat" -> nonEmptyText, "score"-> of[Long], "summaryId"-> nonEmptyText, "dates" -> date("yyyy-MM-dd HH:mm:ss") )(Keyword.apply)(Keyword.unapply) ) def index = Action { Ok(html.index(ta)); } def newTask= Action { implicit request => ta.bindFromRequest.fold( errors => {println(errors) BadRequest(html.index(errors))}, keywo => { Keyword.create(keywo) Ok(views.html.data(Keyword.all())) } ) } models/keyword.scala case class Keyword(id: Pk[Long],word: String,blog: String,cat: String,score: Long, summaryId: String,dates: Date ) object Keyword { val keyw = { get[Pk[Long]]("keyword.id") ~ get[String]("keyword.word")~ get[String]("keyword.blog")~ get[String]("keyword.cat")~ get[Long]("keyword.score") ~ get[String]("keyword.summaryId")~ get[Date]("keyword.dates") map { case id~blog~cat~word~score~summaryId~dates => Keyword(id,word,blog,cat,score, summaryId,dates) } } def all(): List[Keyword] = DB.withConnection { implicit c => SQL("select * from keyword").as(Keyword.keyw *) } def create(key: Keyword){DB.withConnection{implicit c=> SQL("insert into keyword values({word},{blog}, {cat}, {score},{summaryId},{dates})").on('word-> key.word,'blog->key.blog, 'cat -> key.cat, 'score-> key.score, 'summaryId -> key.summaryId, 'dates->new Date()).executeUpdate } } views/index.scala.html @(taskForm: Form[Keyword]) @import helper._ @main("Todo list") { @form(routes.Application.newTask) { @inputText(taskForm("word")) @inputText(taskForm("blog")) @inputText(taskForm("cat")) @inputText(taskForm("score")) @inputText(taskForm("summaryId")) <input type="submit"> <a href="">Go Back</a> } } please give me some idea to store date into mysql databse and date is not a field of form

Read the article

How to generate and encode (for use in GA), random, strict, binary rooted trees with N leaves?

- by Peter Simon

First, I am an engineer, not a computer scientist, so I apologize in advance for any misuse of nomenclature and general ignorance of CS background. Here is the motivational background for my question: I am contemplating writing a genetic algorithm optimizer to aid in designing a power divider network (also called a beam forming network, or BFN for short). The BFN is intended to distribute power to each of N radiating elements in an array of antennas. The fraction of the total input power to be delivered to each radiating element has been specified. Topologically speaking, a BFN is a strictly binary, rooted tree. Each of the (N-1) interior nodes of the tree represents the input port of an unequal, binary power splitter. The N leaves of the tree are the power divider outputs. Given a particular power divider topology, one is still free to map the power divider outputs to the array inputs in an arbitrary order. There are N! such permutations of the outputs. There are several considerations in choosing the desired ordering: 1) The power ratio for each binary coupler should be within a specified range of values. 2) The ordering should be chosen to simplify the mechanical routing of the transmission lines connecting the power divider. The number of ouputs N of the BFN may range from, say, 6 to 22. I have already written a genetic algorithm optimizer that, given a particular BFN topology and desired array input power distribution, will search through the N! permutations of the BFN outputs to generate a design with compliant power ratios and good mechanical routing. I would now like to generalize my program to automatically generate and search through the space of possible BFN topologies. As I understand it, for N outputs (leaves of the binary tree), there are $C_{N-1}$ different topologies that can be constructed, where $C_N$ is the Catalan number. I would like to know how to encode an arbitrary tree having N leaves in a way that is consistent with a chromosomal description for use in a genetic algorithm. Also associated with this is the need to generate random instances for filling the initial population, and to implement crossover and mutations operators for this type of chromosome. Any suggestions will be welcome. Please minimize the amount of CS lingo in your reply, since I am not likely to be acquainted with it. Thanks in advance, Peter

Read the article

Tomcat v7.0 failed to start on Eclipse

- by Questions

Whenever I am running a program on Eclipse, my tomcat is failing to start. I get a dialog box stating this message Server Tomcat v7.0 Server at localhost failed to start. In the console, I am getting this messages Nov 17, 2011 11:56:04 AM org.apache.catalina.core.AprLifecycleListener init INFO: The APR based Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: C:\Program Files\Java\jre6\bin;C:\WINDOWS\Sun\Java\bin;C:\WINDOWS\system32;C:\WINDOWS;C:/Program Files/Java/jre6/bin/client;C:/Program Files/Java/jre6/bin;C:/Program Files/Java/jre6/lib/i386;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\Program Files\Intel\WiFi\bin\;C:\Program Files\Java\jdk1.6.0_01\bin;C:\Program Files\Java\jre1.6.0_01\bin;C:\ILOG\CPLEX_Studio_Preview122\opl\bin\x86_win32;C:\ILOG\CPLEX_Studio_Preview122\opl\oplide\;C:\ILOG\CPLEX_Studio_Preview122\cplex\bin\x86_win32;C:\ILOG\CPLEX_Studio_Preview122\cpoptimizer\bin\x86_win32;;D:\JSP_Setup\eclipse-jee-helios-SR2-win32\eclipse;;. Nov 17, 2011 11:56:04 AM org.apache.tomcat.util.digester.SetPropertiesRule begin WARNING: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property 'source' to 'org.eclipse.jst.jee.server:servletConfigTest' did not find a matching property. Nov 17, 2011 11:56:04 AM org.apache.tomcat.util.digester.SetPropertiesRule begin WARNING: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property 'source' to 'org.eclipse.jst.jee.server:BeerAdvice3' did not find a matching property. Nov 17, 2011 11:56:04 AM org.apache.tomcat.util.digester.SetPropertiesRule begin WARNING: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property 'source' to 'org.eclipse.jst.jee.server:BeerAdvice1' did not find a matching property. Nov 17, 2011 11:56:05 AM org.apache.coyote.http11.Http11Protocol init INFO: Initializing Coyote HTTP/1.1 on http-8080 Nov 17, 2011 11:56:05 AM org.apache.coyote.ajp.AjpProtocol init INFO: Initializing Coyote AJP/1.3 on ajp-8009 Nov 17, 2011 11:56:05 AM org.apache.catalina.startup.Catalina load INFO: Initialization processed in 682 ms Nov 17, 2011 11:56:05 AM org.apache.catalina.core.StandardService startInternal INFO: Starting service Catalina Nov 17, 2011 11:56:05 AM org.apache.catalina.core.StandardEngine startInternal INFO: Starting Servlet Engine: Apache Tomcat/7.0.2 java.lang.reflect.InvocationTargetException at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:288) at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:415) Caused by: java.lang.IllegalArgumentException: Invalid <url-pattern> entry_checking in servlet mapping at org.apache.catalina.core.StandardContext.addServletMapping(StandardContext.java:2823) at org.apache.catalina.core.StandardContext.addServletMapping(StandardContext.java:2799) at org.apache.catalina.deploy.WebXml.configureContext(WebXml.java:1278) at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1255) at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:878) at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:313) at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119) at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:89) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:4667) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:139) at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:988) at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:771) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:139) at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:988) at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:275) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:139) at org.apache.catalina.core.StandardService.startInternal(StandardService.java:427) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:139) at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:649) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:139) at org.apache.catalina.startup.Catalina.start(Catalina.java:585) ... 6 more I had run the code previously, but now it is giving this problems. Also, I went through this post http://forums.opensuse.org/applications/391114-tomcat6-eclipse-not-working.html But is not helping me. Please help at the earliest.

Read the article

iphone quartz drawing 2 lines on top of each other causes worm effect

- by Leonard

I'm using Quartz-2D for iPhone to display a route on a map. The route is colored according to temperature. Because some streets are colored yellow, I am using a slightly thicker black line under the route line to create a border effect, so that yellow parts of the route are spottable on yellow streets. But, even if the black line is as thick as the route line, the whole route looks like a worm (very ugly). I tought this was because I was drawing lines from waypoint to waypoint, instead using the last waypoint as the next starting waypoint. That way if there is a couple of waypoints missing, the route will still have no cuts. What do I need to do to display both lines without a worm effect? -(void) drawRect:(CGRect) rect { CSRouteAnnotation* routeAnnotation = (CSRouteAnnotation*)self.routeView.annotation; // only draw our lines if we're not int he moddie of a transition and we // acutally have some points to draw. if(!self.hidden && nil != routeAnnotation.points && routeAnnotation.points.count > 0) { CGContextRef context = UIGraphicsGetCurrentContext(); Waypoint* fromWaypoint = [[Waypoint alloc] initWithDictionary:[routeAnnotation.points objectAtIndex:0]]; Waypoint* toWaypoint; for(int idx = 1; idx < routeAnnotation.points.count; idx++) { toWaypoint = [[Waypoint alloc] initWithDictionary:[routeAnnotation.points objectAtIndex:idx]]; CLLocation* fromLocation = [fromWaypoint getLocation]; CGPoint fromPoint = [self.routeView.mapView convertCoordinate:fromLocation.coordinate toPointToView:self]; CLLocation* toLocation = [toWaypoint getLocation]; CGPoint toPoint = [self.routeView.mapView convertCoordinate:toLocation.coordinate toPointToView:self]; routeAnnotation.lineColor = [fromWaypoint.weather getTemperatureColor]; CGContextBeginPath(context); CGContextSetLineWidth(context, 3.0); CGContextSetStrokeColorWithColor(context, [UIColor blackColor].CGColor); CGContextMoveToPoint(context, fromPoint.x, fromPoint.y); CGContextAddLineToPoint(context, toPoint.x, toPoint.y); CGContextStrokePath(context); CGContextClosePath(context); CGContextBeginPath(context); CGContextSetLineWidth(context, 3.0); CGContextSetStrokeColorWithColor(context, routeAnnotation.lineColor.CGColor); CGContextMoveToPoint(context, fromPoint.x, fromPoint.y); CGContextAddLineToPoint(context, toPoint.x, toPoint.y); CGContextStrokePath(context); CGContextClosePath(context); fromWaypoint = toWaypoint; } [fromWaypoint release]; [toWaypoint release]; } } Also, I get a <Error>: CGContextClosePath: no current point. error, which I think is bullshit. Please hint me! :)

Read the article

How to pass parameters to Apache Pivot's wtkx:include tag?

- by Andrew Swan

I need to create a reusable UI component that accepts a number of parameters (e.g. an image URL and some label text), similar to how JSP tags can accept parameters. The Pivot docs for the "wtkx:include" tag say: The tag allows a WTKX file to embed content defined in an external WTKX file as if it was defined in the source file itself. This is useful for ... defining reusable content templates I was hoping that I could define my component in a WTKX file using standard Pivot components (e.g. a TextInput) and pass it one or more parameters; for example my reusable template called "row.wtkx" might contain a row with an image and a text field, like this (where the ${xxx} bits are the parameters): <TablePane.Row xmlns="org.apache.pivot.wtk"> <ImageView image="@images/${image_url}" /> <TextInput text="${title}" /> </TablePane.Row> I could then reuse this component within a TablePane as follows: <rows> <TablePane.Row> <Label text="Painting"/> <Label text="Title"/> </TablePane.Row> <wtkx:include src="row.wtkx" image_url="mona_lisa.jpg" title="Mona Lisa"/> <wtkx:include src="row.wtkx" image_url="pearl_earring.jpg" title="Girl with a Pearl Earring"/> <wtkx:include src="row.wtkx" image_url="melting_clocks.jpg" title="Melting Clocks"/> </rows> I've made up the ${...} syntax myself just to show what I'm trying to do. Also, there could be other ways to pass the parameter values other than using attributes of the "wtkx:include" tag itself, e.g. pass a JSON-style map called say "args". The ability to pass parameters like this would make the include tag much more powerful, e.g. in my case allow me to eliminate a lot of duplication between the table row declarations. Or is "wtkx:include" not the right way to be doing this?

Read the article

How to troubleshoot a Highcharts script that's not rendering data when date is added and hanging the JS engine with large datasets?

- by ylluminate

I have a Highchart JS graph that I'm building in Rails (although I don't think Ruby has real bearing on this problem unless it's the Date output format) to which I'm adding the timestamp of each datapoint. Presently the array of floats is rendering fine without timestamps, however when I add the timestamp to the series it fails to rend. What's worse is that when the series has hundreds of entries all sorts of problems arise, not the least of which is the browser entirely hanging and requiring a force quit / kill. I'm using the following to build the array of arrays data series: series1 = readings.map{|row| [(row.date.to_i * 1000), (row.data1.to_f if BigDecimal(row.data1) != BigDecimal("-1000.0"))] } This yields a result like this: series: [{"name":"Data 1","data":[[1326262980000,1.79e-09],[1326262920000,1.29e-09],[1326262860000,1.22e-09],[1326262800000,1.42e-09],[1326262740000,1.29e-09],[1326262680000,1.34e-09],[1326262620000,1.31e-09],[1326262560000,1.51e-09],[1326262500000,1.24e-09],[1326262440000,1.7e-09],[1326262380000,1.24e-09],[1326262320000,1.29e-09],[1326262260000,1.53e-09],[1326262200000,1.23e-09],[1326262140000,1.21e-09]],"color":"blue"}] Yet nothing appears on the graph as noted. Notwithstanding, when I compare the data series in one of their very similar examples here: http://www.highcharts.com/demo/spline-irregular-time It appears that really the data series are formatted identically (except in mine I use the timestamp vs date method). This leads me to think I've got a problem with the timestamp output, but I'm just not able to figure out where / how as I'm converting the date output to an integer multipled by 1000 to convert it to milliseconds as per explained in a similar Railscasts tutorial. I would very much appreciate it if someone could point me in the right direction here as to what I may be doing wrong. What could cause no data to appear on the graph in smaller sized sets (<100 points) and when into the hundreds causes an apparent hang in the javascript engine in this case? Perhaps ultimately the key lies here as this is the entire js that's being generated and not rendering: jQuery(function() { // 1. Define JSON options var options = { chart: {"defaultSeriesType":"spline","renderTo":"chart_name"}, title: {"text":"Title"}, legend: {"layout":"vertical","style":{}}, xAxis: {"title":{"text":"UTC Time"},"type":"datetime"}, yAxis: [{"title":{"text":"Left Title","margin":10}},{"title":{"text":"Right Groups Title"},"opposite":true}], tooltip: {"enabled":true}, credits: {"enabled":false}, plotOptions: {"areaspline":{}}, series: [{"name":"Data 1","data":[[1326262980000,1.79e-08],[1326262920000,1.69e-08],[1326262860000,1.62e-08],[1326262800000,1.42e-08],[1326262740000,1.29e-08],[1326262680000,1.34e-08],[1326262620000,1.31e-08],[1326262560000,1.51e-08],[1326262500000,1.64e-08],[1326262440000,1.7e-08],[1326262380000,1.64e-08],[1326262320000,1.69e-08],[1326262260000,1.53e-08],[1326262200000,1.23e-08],[1326262140000,1.21e-08]],"color":"blue"},{"name":"Data 2","data":[[1326262980000,9.79e-09],[1326262920000,9.78e-09],[1326262860000,9.8e-09],[1326262800000,9.82e-09],[1326262740000,9.88e-09],[1326262680000,9.89e-09],[1326262620000,1.3e-06],[1326262560000,1.32e-06],[1326262500000,1.33e-06],[1326262440000,1.33e-06],[1326262380000,1.34e-06],[1326262320000,1.33e-06],[1326262260000,1.32e-06],[1326262200000,1.32e-06],[1326262140000,1.32e-06]],"color":"red"}], subtitle: {} }; // 2. Add callbacks (non-JSON compliant) // 3. Build the chart var chart = new Highcharts.StockChart(options); });

Search Results

Search found 15206 results on 609 pages for 'identity map pattern'.

Page 581/609 | < Previous Page | 577 578 579 580 581 582 583 584 585 586 587 588 | Next Page >

- by peachykeen

- by Fahim Ahmed

- by Zecrates

- by Monte Chan

- by Az

- by Dan

- by Jay Smith

- by Jeff Lee

- by JGallardo

- by Dman

- by Phineas

- by Geln Yang

- by gablin

- by Daniel Abrahamsson

- by duckworthd

- by Macint

- by baeltazor

- by oo

- by Pietro Luciani

- by Rahul Kulhari

- by Peter Simon

- by Questions

- by Leonard

- by Andrew Swan

- by ylluminate

< Previous Page | 577 578 579 580 581 582 583 584 585 586 587 588 | Next Page >