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  • Java order jlist by status

    - by Takami
    i have a small problem, i don't know how to sort my jlist by status which is retrieved from database. i want sort by "online" and "offline", i mean online computers go first and then offline computers, i have this code now, it just makes the icon+text for the jlist Can you tell me how can i filter/sortby status? public void acx_pc(String query) { try { Statement st = con.createStatement(); ResultSet rs = st.executeQuery(query); String comb; Map<Object, Icon> icons = new HashMap<>(); ArrayList<String> pc_list = new ArrayList<>(); int i = 0; while (rs.next()) { //Getting info from DB String pc_name = rs.getString("nombre_pc"); String pc_ip = rs.getString("IP"); String status = rs.getString("estado"); //Setting text for the jList comb = pc_name + " - " + pc_ip; //Comparing Status switch (status) { case "online": //This is just for rendering an image+text to Jlist icons.put(comb, new ImageIcon(getClass().getResource("/Imagenes/com_on_30x30.png"))); break; case "offline": //This is just for rendering an image to Jlist icons.put(comb, new ImageIcon(getClass().getResource("/Imagenes/com_off_30x30.png"))); break; } //Adding info to ArrayList pc_list.add(i, comb); i++; } con.close(); // Setting the list/text on Jlist Home.computer_jlist.setListData(pc_list.toArray()); // create a cell renderer to add the appropriate icon Home.computer_jlist.setCellRenderer(new pc_cell_render(icons)); } catch (Exception e) { System.out.println("Error aqui: " + e); } } I want to do something like (should automatically order) http://imageshack.us/a/img27/9018/2mx1.png and not: http://imageshack.us/a/img407/346/e9r.png

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  • Java syntax of +

    - by Pindatjuh
    Why is the following syntax correct: x = y+++y; (Where it means y++ + y or y + ++y which both mean y * 2 + 1) But this is not valid syntax: x = y+++++y; (Which should mean y++ + ++y, which must mean y and increase y and then add ++y which increases y thus y * 2 + 2) Is there a reason for this?

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  • Getter/Setter Problem in Java?

    - by Praveen Chandrasekaran
    Hi Folks, I want to pass the String value between the classes both are same package. so i created the the classs like the code: public class Map_Delegate { String myLatitude; String myLongitude; String myName; private String TAG = "Map_Delegate"; public String getMyName() { return this.myName; } public void setMyName(String value) { Log.v(TAG, value); this.myName = value; } public String getMyLatitude() { return this.myLatitude; } public void setMyLatitude(String value) { Log.v(TAG, value); this.myLatitude = value; } public String getMyLongitude() { return this.myLongitude; } public void setMyLongitude(String value) { Log.v(TAG, value); this.myLongitude = value; } } But it can't pass the value. I done like this code to set the value: Map_Delegate map = new Map_Delegate(); map.setMyName(first_name_temp + " " + last_name_temp); map.setMyLatitude(homeLatitude_temp); map.setMyLongitude(homeLongitude_temp); code to get the value: Map_Delegate map = new Map_Delegate(); name_val = getMyName(); lat_val = getMyLatitude(); long_val = getMyLongitude(); Why get the Null value can you Guess? All classes in the same package and public .AnyIdea?

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  • Slowing process creation under Java?

    - by oconnor0
    I have a single, large heap (up to 240GB, though in the 20-40GB range for most of this phase of execution) JVM [1] running under Linux [2] on a server with 24 cores. We have tens of thousands of objects that have to be processed by an external executable & then load the data created by those executables back into the JVM. Each executable produces about half a megabyte of data (on disk) that when read right in, after the process finishes, is, of course, larger. Our first implementation was to have each executable handle only a single object. This involved the spawning of twice as many executables as we had objects (since we called a shell script that called the executable). Our CPU utilization would start off high, but not necessarily 100%, and slowly worsen. As we began measuring to see what was happening we noticed that the process creation time [3] continually slows. While starting at sub-second times it would eventually grow to take a minute or more. The actual processing done by the executable usually takes less than 10 seconds. Next we changed the executable to take a list of objects to process in an attempt to reduce the number of processes created. With batch sizes of a few hundred (~1% of our current sample size), the process creation times start out around 2 seconds & grow to around 5-6 seconds. Basically, why is it taking so long to create these processes as execution continues? [1] Oracle JDK 1.6.0_22 [2] Red Hat Enterprise Linux Advanced Platform 5.3, Linux kernel 2.6.18-194.26.1.el5 #1 SMP [3] Creation of the ProcessBuilder object, redirecting the error stream, and starting it.

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  • Java loop to collect the second and third elements every three in an array

    - by mhollander38
    I have a file with data in the form timestamp, coordinate, coordinate, seperated by spaces, as here; 14:25:01.215 370.0 333.0 I need to loop through and add the coordinates only to an array. The data from the file is read in and put into as String[] called info, from split(" "). I have two problems, I think the end of the file has a extra " " which I need to lose appropriately and I also want confirmation/suggestions of my loop, at the moment I am getting sporadic out of bounds exceptions. My loop is as follows; String[] info; info = dataHolder.split(" "); ArrayList<String> coOrds1 = new ArrayList<String>(); for (int counter = 0; counter < info.length; counter = counter+3) { coOrds1.add(info[counter+1]); coOrds1.add(info[counter+2]); } Help and suggestions appreciated. The text file is here but the class receives in a UDP packet from another class so I am unsure if this potentially adds " " at the end or not.

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  • How to validate overlapping no in java

    - by anandhinaveen
    I Have dynamically render row. WE have fields like FROM TO. For eg: From TO 2 10, 2 3, 8 12 It cannot accept this combination row.. That means no number should be overlapping. For eg: From TO 2 10, 0 1, 11 12 This combination is allowed.the row may also increased. I need need to write a validation for this overlapping. Can any 1 help to solve this problem.

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  • Java split is eating my characters.

    - by Fenris_uy
    Hi, I have a string like this String str = "la$le\$li$lo". I want to split it to get the following output "la","le\$li","lo". The \$ is a $ escaped so it should be left in the output. But when I do str.split("[^\\\\]\\$") y get "l","le\$l","lo". From what I get my regex is matching a$ and i$ and removing then. Any idea of how to get my characters back? Thanks

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  • How to build our own java custom layout

    - by nguyendat
    Please help me how to creat own custom layout, container, component, layout manager... Example: Containers and Layout Managers Create a window frame. Nest panels within a frame for better layout control. Create and display buttons in a panel. List two component attributes that are controlled by a layout manager. Set the layout manager for a container. Place components in a panel using BorderLayout, GridLayout, and FlowLayout. Name one advantage of each of the layout managers. Create panels with titles. i was search on google but can't find any that match my requirement Thanks for your help

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  • Getting a java collection of objects in Alphabetical order

    - by MichaelMcCabe
    I have a question that I dont really know where to start. So I thought i'd ask it here. Basically, I have a drop down with names in it. I want these names to be in alphabetical order. Populating the drop down happens as follows; I query a database and pull down an Id and Name, make a object called "UserList", and set the name and id variables with what I get back. I then add this object to an ArrayList. I do this over and over. I then convert this collection to an array, and pass it to my JSP page using session.setAttribute("userList", UserList); I then populate the drop down as below. <c:forEach items="${usersCompanysList}" var="c" > There probably is a simple answer but how to I sort these names?

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  • ByteArrayOutputStream to PrintWriter (Java Servlet)

    - by Thomas
    Writing generated PDF (ByteArrayOutputStream) in a Servlet to PrintWriter. I am desperately looking for a way to write a generated PDF file to the response PrintWriter. Since a Filter up the hierarchy chain has already called response.getWriter() I can't get response.getOutputStream(). I do have a ByteArrayOutputStream where I generated the PDF into. Now all I need is a way to output the content of this ByteArrayOutputStream to the PrintWriter. If anyone could give me a helping hand would be very much appreciated!

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  • Java overloading and overriding

    - by Padmanabh
    We always say that method overloading is static polymorphism and overriding is runtime polymorphism. What exactly do we mean by static here? Is the call to a method resolved on compiling the code? So whats the difference between normal method call and calling a final method? Which one is linked at compile time?

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  • Problem in arranging contents of Class in JAVA

    - by LuckySlevin
    Hi, I have some classes and I'm trying to fill the objects of this class. Here is what i've tried. (Question is at the below) public class Team { private String clubName; private String preName; private ArrayList<String> branches; public Team(String clubName, String preName) { this.clubName = clubName; this.preName = preName; branches = new ArrayList<String>(); } public Team() { // TODO Auto-generated constructor stub } public String getClubName() { return clubName; } public String getPreName() { return preName; } public ArrayList<String> getBranches() { return branches; } public void setClubName(String clubName) { this.clubName = clubName; } public void setPreName(String preName) { this.preName = preName; } public void setBranches(ArrayList<String> branches) { this.branches = branches; } } public class Branch { private ArrayList<Player> players = new ArrayList<Player>(); String brName; public Branch() {} public void setBr(String brName){this.brName = brName;} public String getBr(){return brName;} public ArrayList<Player> getPlayers() { return players; } public void setPlayers(ArrayList<Player> players) { this.players = players; } } //TEST CLASS public class test { /** * @param args * @throws IOException */ public static void main(String[] args) throws IOException { String a,b,c; String q = "q"; int brCount = 0, tCount = 0; BufferedReader input = new BufferedReader(new InputStreamReader(System.in)); Team[] teams = new Team[30]; Branch[] myBranch = new Branch[30]; for(int z = 0 ; z <30 ;z++) { teams[z] = new Team(); myBranch[z] = new Branch(); } ArrayList<String> tmp = new ArrayList<String>(); int k = 0; int secim = Integer.parseInt(input.readLine()); while(secim != 0) { if(k!=0) secim = Integer.parseInt(input.readLine()); k++; switch(secim) { case 1 : brCount = 0; a = input.readLine(); teams[tCount].setClubName(a); b= input.readLine(); teams[tCount].setPreName(b); c = input.readLine(); while(c.equals(q) == false) { if(brCount != 0) {c = input.readLine();} if(c.equals(q)== false){ myBranch[brCount].brName = c; tmp.add(myBranch[brCount].brName); brCount++; } System.out.println(brCount); } teams[tCount].setBranches(tmp); for(int i=0;i<=tCount;i++ ){ System.out.print("a :" + teams[i].getClubName()+ " " + teams[i].getPreName()+ " "); System.out.println(teams[i].getBranches());} tCount++; break; case 2: String src = input.readLine();//LATERRRRRRRr } } } } The problem is one of my class elements. I have an arraylist as an element of a class. When i enter: AAA as preName BBB as clubName c d e as Branches Then as a second element www as preName GGG as clubName a b as branches The result is coming like: AAA BBB c,d,e,a,b GGG www c,d,e,a,b Which means ArrayList part of the class is putting it on and on. I tried to use clear() method but caused problems. Any ideas.

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  • PasswordFiled char[] to String in Java connection MySql?

    - by user1819551
    This is a jFrame to connect to the database and this is in the button connect. My issue is in the passwordField NetBeans make me do a char[], but my .getConnection not let me insert the char[] ERROR: "no suitable method found for getConnection(String,String,char[])". So I will change to String right? So when I change and run the jFrame said access denied. when I start doing the System.out.println(l) " Give me the right answer" Like this: "Alex". But when I do the System.out.println(password) "Give me the Array spaces and not the value" Like this: jdbc:mysql://localhost/home inventory root [C@5be5ab68 <--- Array space . What I doing wrong? try { Class.forName("org.gjt.mm.mysql.Driver"); //Load the driver String host = "jdbc:mysql://"+tServerHost.getText()+"/"+tSchema.getText(); String uName = tUsername.getText(); char[] l = pPassword.getPassword(); System.out.println(l); String password= l.toString(); System.out.println(host+uName+l); con = DriverManager.getConnection(host, uName, password); System.out.println(host+uName+password); } catch (SQLException | ClassNotFoundException ex) { JOptionPane.showMessageDialog(this, ex.getMessage()); } }

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  • Splitting up input using regular expressions in Java

    - by Joe24
    I am making a program that lets a user input a chemical for example C9H11N02. When they enter that I want to split it up into pieces so I can have it like C9, H11, N, 02. When I have it like this I want to make changes to it so I can make it C10H12N203 and then put it back together. This is what I have done so far. using the regular expression I have used I can extract the integer value, but how would I go about get C10, H11 etc..? System.out.println("Enter Data"); Scanner k = new Scanner( System.in ); String input = k.nextLine(); String reg = "\\s\\s\\s"; String [] data; data = input.split( reg ); int m = Integer.parseInt( data[0] ); int n = Integer.parseInt( data[1] );

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  • Help making a button open another app with Java/Android

    - by user569503
    I am trying to learn to make a simple app that opens a couple of other apps to eliminate the need for another apps. I just can't figure it out. From reading here and other places it seems this should work. Button batteryhistory = (Button)findViewById(R.string.BatteryHistoryButtonDialog); batteryhistory.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { Intent i = new Intent(); ComponentName n = new ComponentName("com.android.settings", "com.android.settings.BatteryHistory"); i.setComponent(n); startActivity(i); Thanks so much for the help :D

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  • Searching in a TreeMap (Java)

    - by Kronen
    I need to do a search in a map of maps and return the keys this element belong. I think this implementation is very slow, can you help me to optimize it?. I need to use TreeSet and I can't use contains because they use compareTo, and equals/compareTo pair are implemented in an incompatible way and I can't change that. (sorry my bad english) Map m = new TreeSet(); public String getKeys(Element element) { for(Entry e : m.entrySet()) { mapSubKey = e.getValue(); for(Entry e2 : mapSubKey.entrySet()) { setElements = e2.getValue(); for(Element elem : setElements) if(elem.equals(element)) return "Key: " + e.getKey() + " SubKey: " + e2.getKey(); } } }

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  • Java Map question

    - by user552961
    I have one Map that contains some names and numbers Map<String,Integer> abc = new TreeMap<String,Integer>(); It works fine. I can put some values in it but when I call it in different class it gives me wrong order. For example: I putted abc.put("a",1); abc.put("b",5); abc.put("c",3); some time it returns the order (b,a,c) and some time (a,c,b). What is wrong with it? Is there any step that I am missing when I call this map?

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  • Passing a class ("Country.class") as an argument in Java

    - by Coronatus
    I'm trying to make a method that takes an argument of Country.class, User.class etc, and returns argument.count(). All the possible classes that I would give to this method extend from Model and have the method count(). My code: private static long <T> countModel(Model<T> clazz) { return clazz.count(); } Called by: renderArgs.put("countryCount", countModel(Country.class)); However this just doesn't work at all. How do I do this, please?

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  • Container of Generic Types in java

    - by Cyker
    I have a generic class Foo<T> and parameterized types Foo<String> and Foo<Integer>. Now I want to put different parameterized types into a single ArrayList. What is the correct way of doing this? Candidate 1: public class MMM { public static void main(String[] args) { Foo<String> fooString = new Foo<String>(); Foo<Integer> fooInteger = new Foo<Integer>(); ArrayList<Foo<?> > list = new ArrayList<Foo<?> >(); list.add(fooString); list.add(fooInteger); for (Foo<?> foo : list) { // Do something on foo. } } } class Foo<T> {} Candidate 2: public class MMM { public static void main(String[] args) { Foo<String> fooString = new Foo<String>(); Foo<Integer> fooInteger = new Foo<Integer>(); ArrayList<Foo> list = new ArrayList<Foo>(); list.add(fooString); list.add(fooInteger); for (Foo foo : list) { // Do something on foo. } } } class Foo<T> {} In a word, it is related to the difference between Foo<?> and the raw type Foo. Update: Grep What is the difference between the unbounded wildcard parameterized type and the raw type? on this link may be helpful.

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  • Sequence of the Events in Java

    - by ozlegolas
    Hi, I have two events for two seperate components, but there is a problem. JTabbedPane's stateChanged event is fired before JFormattedField's focusLost event. Is there a way of making stateChange event to be fired after focusLost event. Thanks, Tuna

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