Search Results

Search found 55437 results on 2218 pages for 'oracle berkeley db java edition'.

Page 777/2218 | < Previous Page | 773 774 775 776 777 778 779 780 781 782 783 784  | Next Page >

• Climbing boxes in box2D

  - by Rothens

  I've just stepped into the world of Box2D with libgdx. I've already made a stack of boxes: They are dropped randomly ontop of each other. What I'd like to achieve is to make a character, that could freely climb on the boxes, (He can grip on the boxes anywhere, not just on the side/top of a box) but his weight affects the stack as well, so the boxes could fall down. My google-fu failed me... Is there any way to make this possible?

  Read the article

• Having trouble with pathfinding

  - by user2144536

  I'm trying to implement pathfinding in a game I'm programming using this method. I'm implementing it with recursion but some of the values after the immediate circle of tiles around the player are way off. For some reason I cannot find the problem with it. This is a screen cap of the problem: The pathfinding values are displayed in the center of every tile. Clipped blocks are displayed with the value of 'c' because the values were too high and were covering up the next value. The red circle is the first value that is incorrect. The code below is the recursive method. //tileX is the coordinates of the current tile, val is the current pathfinding value, used[][] is a boolean //array to keep track of which tiles' values have already been assigned public void pathFind(int tileX, int tileY, int val, boolean[][] used) { //increment pathfinding value int curVal = val + 1; //set current tile to true if it hasn't been already used[tileX][tileY] = true; //booleans to know which tiles the recursive call needs to be used on boolean topLeftUsed = false, topUsed = false, topRightUsed = false, leftUsed = false, rightUsed = false, botomLeftUsed = false, botomUsed = false, botomRightUsed = false; //set value of top left tile if necessary if(tileX - 1 >= 0 && tileY - 1 >= 0) { //isClipped(int x, int y) returns true if the coordinates givin are in a tile that can't be walked through (IE walls) //occupied[][] is an array that keeps track of which tiles have an enemy in them // //if the tile is not clipped and not occupied set the pathfinding value if(isClipped((tileX - 1) * 50 + 25, (tileY - 1) * 50 + 25) == false && occupied[tileX - 1][tileY - 1] == false && !(used[tileX - 1][tileY - 1])) { pathFindingValues[tileX - 1][tileY - 1] = curVal; topLeftUsed = true; used[tileX - 1][tileY - 1] = true; } //if it is occupied set it to an arbitrary high number so enemies find alternate routes if the best is clogged if(occupied[tileX - 1][tileY - 1] == true) pathFindingValues[tileX - 1][tileY - 1] = 1000000000; //if it is clipped set it to an arbitrary higher number so enemies don't travel through walls if(isClipped((tileX - 1) * 50 + 25, (tileY - 1) * 50 + 25) == true) pathFindingValues[tileX - 1][tileY - 1] = 2000000000; } //top middle if(tileY - 1 >= 0 ) { if(isClipped(tileX * 50 + 25, (tileY - 1) * 50 + 25) == false && occupied[tileX][tileY - 1] == false && !(used[tileX][tileY - 1])) { pathFindingValues[tileX][tileY - 1] = curVal; topUsed = true; used[tileX][tileY - 1] = true; } if(occupied[tileX][tileY - 1] == true) pathFindingValues[tileX][tileY - 1] = 1000000000; if(isClipped(tileX * 50 + 25, (tileY - 1) * 50 + 25) == true) pathFindingValues[tileX][tileY - 1] = 2000000000; } //top right if(tileX + 1 <= used.length && tileY - 1 >= 0) { if(isClipped((tileX + 1) * 50 + 25, (tileY - 1) * 50 + 25) == false && occupied[tileX + 1][tileY - 1] == false && !(used[tileX + 1][tileY - 1])) { pathFindingValues[tileX + 1][tileY - 1] = curVal; topRightUsed = true; used[tileX + 1][tileY - 1] = true; } if(occupied[tileX + 1][tileY - 1] == true) pathFindingValues[tileX + 1][tileY - 1] = 1000000000; if(isClipped((tileX + 1) * 50 + 25, (tileY - 1) * 50 + 25) == true) pathFindingValues[tileX + 1][tileY - 1] = 2000000000; } //left if(tileX - 1 >= 0) { if(isClipped((tileX - 1) * 50 + 25, (tileY) * 50 + 25) == false && occupied[tileX - 1][tileY] == false && !(used[tileX - 1][tileY])) { pathFindingValues[tileX - 1][tileY] = curVal; leftUsed = true; used[tileX - 1][tileY] = true; } if(occupied[tileX - 1][tileY] == true) pathFindingValues[tileX - 1][tileY] = 1000000000; if(isClipped((tileX - 1) * 50 + 25, (tileY) * 50 + 25) == true) pathFindingValues[tileX - 1][tileY] = 2000000000; } //right if(tileX + 1 <= used.length) { if(isClipped((tileX + 1) * 50 + 25, (tileY) * 50 + 25) == false && occupied[tileX + 1][tileY] == false && !(used[tileX + 1][tileY])) { pathFindingValues[tileX + 1][tileY] = curVal; rightUsed = true; used[tileX + 1][tileY] = true; } if(occupied[tileX + 1][tileY] == true) pathFindingValues[tileX + 1][tileY] = 1000000000; if(isClipped((tileX + 1) * 50 + 25, (tileY) * 50 + 25) == true) pathFindingValues[tileX + 1][tileY] = 2000000000; } //botom left if(tileX - 1 >= 0 && tileY + 1 <= used[0].length) { if(isClipped((tileX - 1) * 50 + 25, (tileY + 1) * 50 + 25) == false && occupied[tileX - 1][tileY + 1] == false && !(used[tileX - 1][tileY + 1])) { pathFindingValues[tileX - 1][tileY + 1] = curVal; botomLeftUsed = true; used[tileX - 1][tileY + 1] = true; } if(occupied[tileX - 1][tileY + 1] == true) pathFindingValues[tileX - 1][tileY + 1] = 1000000000; if(isClipped((tileX - 1) * 50 + 25, (tileY + 1) * 50 + 25) == true) pathFindingValues[tileX - 1][tileY + 1] = 2000000000; } //botom middle if(tileY + 1 <= used[0].length) { if(isClipped((tileX) * 50 + 25, (tileY + 1) * 50 + 25) == false && occupied[tileX][tileY + 1] == false && !(used[tileX][tileY + 1])) { pathFindingValues[tileX][tileY + 1] = curVal; botomUsed = true; used[tileX][tileY + 1] = true; } if(occupied[tileX][tileY + 1] == true) pathFindingValues[tileX][tileY + 1] = 1000000000; if(isClipped((tileX) * 50 + 25, (tileY + 1) * 50 + 25) == true) pathFindingValues[tileX][tileY + 1] = 2000000000; } //botom right if(tileX + 1 <= used.length && tileY + 1 <= used[0].length) { if(isClipped((tileX + 1) * 50 + 25, (tileY + 1) * 50 + 25) == false && occupied[tileX + 1][tileY + 1] == false && !(used[tileX + 1][tileY + 1])) { pathFindingValues[tileX + 1][tileY + 1] = curVal; botomRightUsed = true; used[tileX + 1][tileY + 1] = true; } if(occupied[tileX + 1][tileY + 1] == true) pathFindingValues[tileX + 1][tileY + 1] = 1000000000; if(isClipped((tileX + 1) * 50 + 25, (tileY + 1) * 50 + 25) == true) pathFindingValues[tileX + 1][tileY + 1] = 2000000000; } //call the method on the tiles that need it if(tileX - 1 >= 0 && tileY - 1 >= 0 && topLeftUsed) pathFind(tileX - 1, tileY - 1, curVal, used); if(tileY - 1 >= 0 && topUsed) pathFind(tileX , tileY - 1, curVal, used); if(tileX + 1 <= used.length && tileY - 1 >= 0 && topRightUsed) pathFind(tileX + 1, tileY - 1, curVal, used); if(tileX - 1 >= 0 && leftUsed) pathFind(tileX - 1, tileY, curVal, used); if(tileX + 1 <= used.length && rightUsed) pathFind(tileX + 1, tileY, curVal, used); if(tileX - 1 >= 0 && tileY + 1 <= used[0].length && botomLeftUsed) pathFind(tileX - 1, tileY + 1, curVal, used); if(tileY + 1 <= used[0].length && botomUsed) pathFind(tileX, tileY + 1, curVal, used); if(tileX + 1 <= used.length && tileY + 1 <= used[0].length && botomRightUsed) pathFind(tileX + 1, tileY + 1, curVal, used); }

  Read the article

• Can I install an Ubuntu app from remote laptop?

  - by Voidcode

  Is their a way to push/send and ubuntu-app/deb-file to be install on my Ubuntu laptop? Usecase... Laptop 1. I find an app, I need to install! But I´am not at home. I just push it to my other laptop to be install.. Laptop 2. I am now at home. My laptop 2 view an dialog asking to install the app I send from laptop 1. Can this be do?.. SSH? Question-update Can it be done so it open Ubuntu Software Center and then laptop2-user only need to write their password and press ok? for non-tec users.. like my father...

  Read the article

• LibGDX - Textures rendering at wrong position

  - by ACluelessGuy

  Update 2: Let me further explain my problem since I think that i didn't make it clear enough: The Y-coordinates on the bottom of my screen should be 0. Instead it is the height of my screen. That means the "higher" i touch/click the screen the less my y-coordinate gets. Above that the origin is not inside my screen, atleast not the 0 y-coordinate. Original post: I'm currently developing a tower defence game for fun by using LibGDX. There are places on my map where the player is or is not allowed to put towers on. So I created different ArrayLists holding rectangles representing a tile on my map. (towerPositions) for(int i = 0; i < map.getLayers().getCount(); i++) { curLay = (TiledMapTileLayer) map.getLayers().get(i); //For all Cells of current Layer for(int k = 0; k < curLay.getWidth(); k++) { for(int j = 0; j < curLay.getHeight(); j++) { curCell = curLay.getCell(k, j); //If there is a actual cell if(curCell != null) { tileWidth = curLay.getTileWidth(); tileHeight = curLay.getTileHeight(); xTileKoord = tileWidth*k; yTileKoord = tileHeight*j; switch(curLay.getName()) { //If layer named "TowersAllowed" picked case "TowersAllowed": towerPositions.add(new Rectangle(xTileKoord, yTileKoord, tileWidth, tileHeight)); // ... AND SO ON If the player clicks on a "allowed" field later on he has the opportunity to build a tower of his coice via a menu. Now here is the problem: The towers render, but they render at wrong position. (They appear really random on the map, no certain pattern for me) for(Rectangle curRect : towerPositions) { if(curRect.contains(xCoord, yCoord)) { //Using a certain tower in this example (left the menu out if(gameControl.createTower("towerXY")) { //RenderObject is just a class holding the Texture and x/y coordinates renderList.add(new RenderObject(new Texture(Gdx.files.internal("TowerXY.png")), curRect.x, curRect.y)); } } } Later on i render it: game.batch.begin(); for(int i = 0; i < renderList.size() ; i++) { game.batch.draw(renderList.get(i).myTexture, renderList.get(i).x, renderList.get(i).y); } game.batch.end(); regards

  Read the article

• How to store a list of Objects that might change in future?

  - by Amogh Talpallikar

  I have set of Objects of the same class which have different values of their attributes. and I need to find the best match from a function under given scenarios out of these objects. In future these objects might increase as well. Quite similar to the way we have Color class in awt. we have some static color objects in the class with diff rgb values. But in my case say, I need to chose the suitable color out of these static ones based on certain criteria. So should I keep them in an arrayList or enum or keep them as static vars as in case of Colors. because I will need to parse through all of them and decide upon the best match. so I need them in some sort of collection. But in future if I need to add another type I will have to modify the class and add another list.add(object) call for this one and then it will violate the open-close principle. How should I go about it ?

  Read the article

• BigDecimal.floatValue versus Float.valueOf

  - by Frank

  Has anybody ever come across this: System.out.println("value of: " + Float.valueOf("3.0f")); // ok, prints 3.0 System.out.println(new BigDecimal("3.0f").floatValue()); // NumberFormatException I would argue that the lack of consistency here is a bug, where BigDecimal(String) doesn't follow the same spec as Float.valueOf() (I checked the JDK doc). I'm using a library that forces me to go through BigDecimal, but it can happen that I have to send "3.0f" there. Is there a known workaround (BigDecimal is inaccessible in a library).

  Read the article

• Datenbank Speicherplatz überwachen mit dem Segment Advisor

  - by Ulrike Schwinn (DBA Community)

  Wie kritisch ist die Belegung des Speicherplatzes innerhalb der Tablespaces? Können vielleicht einige Segmente verkleinert bzw. reorganisiert werden, die unnötigen Platz verbrauchen? Um Antworten auf diese Fragen zu erhalten, gibt es die Möglichkeit unterschiedliche Data Dictionary Views wie DBA_SEGMENTS, DBA_EXTENTS und DBA_FREE_SPACE abzufragen bzw. Packages wie DBMS_SPACE zur detaillierten Analyse zu verwenden. Zusätzlich gibt es in der Oracle Datenbank spezielle mitgelieferte Advisors, die bei der Analyse des Speicherplatzes und der Objekte eine gewisse Unterstützung liefern können - den sogenannten Segment und den Compression Advisor. Der aktuelle Artikel in der DBA Community illustriert díe Verwendungsweise des Segment Advisors.

  Read the article

• How to revert to Eclipse's old behavior when double-clicking on frames or windows, in Juno?

  - by mattquiros

  I find Eclipse Juno very counter-intuitive. In my workspace, I used to just have the package view at the left, my code on the right, and whenever I'm printing something in the console, that's only when the console frame shows up from the bottom right. When you double click on a particular window, it either only goes fullscreen within Eclipse, or back to its original size together with the size of the other frames. In Juno, however, it seems that frames are put on layers on top of each other. When I print something to the console, the output frame only shows up as a small, useless square to my right. When I double-click, it goes full screen. When I double-click again, it occupies the full right frame, hiding my code. I double-click again and it goes full screen, then it double-clicks before it shares the right frame with my code on top of it. Then when I minimize it, it goes to the side. Any way to go back to the good old days of Eclipse? Thanks.

  Read the article

• Move Camera Freely Around Object While Looking at It

  - by Alex_Hyzer_Kenoyer

  I've got a 3D model loaded (a planet) and I have a camera that I want to allow the user to move freely around it. I have no problem getting the camera to orbit the planet around either the x or y axis. My problem is when I try to move the camera on a different axis I have no idea how to go about doing it. I am using OpenGL on Android with the libGDX library. I want the camera to orbit the planet in the direction that the user swipes their finger on the screen.

  Read the article

• Platformer Collision Error [closed]

  - by Connor

  I am currently working on a relatively simple platform game that has an odd bug.You start the game by falling onto the ground (you spawn a few blocks above the ground), but when you land your feet get stuck INSIDE the world and you can't move until you jump. Here's what I mean: The player's feet are a few pixels below the ground level. However, this problem only occurs in 3 places throughout the map and only in those 3 select places. I'm assuming that the problem lies within my collision detection code but I'm not entirely sure, as I don't get an error when it happens. public boolean isCollidingWithBlock(Point pt1, Point pt2) { //Checks x for(int x = (int) (this.x / Tile.tileSize); x < (int) (this.x / Tile.tileSize + 4); x++) { //Checks y for(int y = (int) (this.y / Tile.tileSize); y < (int) (this.y / Tile.tileSize + 4); y++) { if(x >= 0 && y >= 0 && x < Component.dungeon.block.length && y < Component.dungeon.block[0].length) { //If the block is not air if(Component.dungeon.block[x][y].id != Tile.air) { //If the player is in contact with point one or two on the block if(Component.dungeon.block[x][y].contains(pt1) || Component.dungeon.block[x][y].contains(pt2)) { //Checks for specific blocks if(Component.dungeon.block[x][y].id == Tile.portalBlock) { Component.isLevelDone = true; } if(Component.dungeon.block[x][y].id == Tile.spike) { Health.health -= 1; Component.isJumping = true; if(Health.health == 0) { Component.isDead = true; } } return true; } } } } } return false; } What I'm asking is how I would fix the problem. I've looked over my code for quite a while and I'm not sure what's wrong with it. Also, if there's a more efficient way to do my collision checking then please let me know! I hope that is enough information, if it's not just tell me what you need and I'll be sure to add it. Thank you! [EDIT] Jump code: if(!isJumping && !isCollidingWithBlock(new Point((int) x + 2, (int) (y + height)), new Point((int) (x + width + 2), (int) (y + height)))) { y += fallSpeed; //sY is the screen's Y. The game is a side-scroller Component.sY += fallSpeed; } else { if(Component.isJumping) { isJumping = true; } } if(isJumping) { if(!isCollidingWithBlock(new Point((int) x + 2, (int) y), new Point((int) (x + width + 2), (int) y))) { if(jumpCount >= jumpHeight) { isJumping = false; jumpCount = 0; } else { y -= jumpSpeed; Component.sY -= jumpSpeed; jumpCount += 1; } } else { isJumping = false; jumpCount = 0; } }

  Read the article

• Bukkit send a custom placed name plate?

  - by HcgRandon

  Hello i have been working on a part of my plugin that has waypoints allowing the user to create delete etc. I got to thinking after using and seeing a couple of the disguse plugins. That maybe i could create a command toggle that would show the user where the waypoints they have are! I know how to do all of this i just have no idea how to display a nameplate to the client. I know its possible because disguisecraft does it i tried looking though their code but couldent find much... I belive to get this effect i need to send packets to the client if someone can direct me to a list of bukkit packets or even a solution to sending the client a custom located nameplate that would be fantastic! Thanks in advanced.

  Read the article

• External classes positions don't work?

  - by SystemNetworks

  I have an external class which reads the user's mouse clicks. I gave a position where the user have to click, and when the user clicks on that position, it would turn my boolean "mouse" to true. But when I connect that to my game(state based) class, it does not work. Here's the code: External class public void UI(Input input, GameContainer gc, float posX, float posY) { int x = Mouse.getX(); int y = Mouse.getY(); if(posX<=100 && posY<=100) { if(Mouse.isButtonDown(1)) { mouse = true; } } } Game class(main) public void update(GameContainer gc, StateBasedGame sbg, int delta) throws SlickException { int x = Mouse.getX(); int y = Mouse.getY(); civ.UI(input, gc, x,y); } The problem is when I click my mouse at posX<=100 && posY<=100. It does not work.

  Read the article

• Use decorator and factory together to extend objects?

  - by TheClue

  I'm new to OOP and design pattern. I've a simple app that handles the generation of Tables, Columns (that belong to Table), Rows (that belong to Column) and Values (that belong to Rows). Each of these object can have a collection of Property, which is in turn defined as an enum. They are all interfaces: I used factories to get concrete instances of these products, depending on circumnstances. Now I'm facing the problem of extending these classes. Let's say I need another product called "SpecialTable" which in turn has some special properties or new methods like 'getSomethingSpecial' or an extended set of Property. The only way is to extend/specialize all my elements (ie. build a SpecialTableFactory, a SpecialTable interface and a SpecialTableImpl concrete)? What to do if, let's say, I plan to use standard methods like addRow(Column column, String name) that doesn't need to be specialized? I don't like the idea to inherit factories and interfaces, but since SpecialTable has more methods than Table i guess it cannot share the same factory. Am I wrong? Another question: if I need to define product properties at run time (a Table that is upgraded to SpecialTable at runtime), i guess i should use a decorator. Is it possible (and how) to combine both factory and decorator design? Is it better to use a State or Strategy pattern, instead?

  Read the article

• More smaller maps among which player can travel

  - by davidv

  I am developing 2d game, where maps are tile based, small about 20x20 tiles and player can travel between a lot of maps (in my game rooms) like this. The maps are connected sometimes verticaly and sometimes horizontaly and together they make one big cave. Should I create a class where one 2d array holds all the maps (another 2d arrays), or is there any other way? Whats the most efficient way to create them in this class? Thank you for your help.

  Read the article

• Community Forum at Openworld - Presentations available

  - by Javier Puerta

  Thanks to all of you who participated at the Exadata & Manageability Partner Community session that we ran during Oracle Openworld in San Francisco. Very special thanks to the partner speakers who shared their experiences with the rest of the community! Presentation On October 1st we held a new session of the Exadata & Manageability Partner Community in San Francisco. Thanks to all of you who participated in the event and very especially to the partner speakers who shares their experiences with the rest of the community: Francisco Bermúdez (Capgemini Spain), Dmitry Krasilov (Nvision, Russia) and Miguel Alves (WeDo Technologies, Portugal)The slide decks used in the presentations are now available for download at the Exadata Partner Community Collaborative Workspace (for community members only - if you get an error message, please register for the Community first).In a few weeks we will be announcing the location for the next Community event in the spring timeframe.

  Read the article

• JEE project(s) to show prospective employers

  - by My code has no bugs

  I'm studying JEE and want to get employed doing JEE work in the near future. From reading this website and various others, I now know that many employers value a github profile with code samples, projects and the like. Since I want to get hired doing JEE stuff, what kind of projects can I work on to eventually place on github showing prospective employers? Is there any (non-nonsense) project(s) which uses the JEE stack I can work on ?

  Read the article

• Algorithms for Data Redundancy and Failover for distributed storage system?

  - by kennetham

  I'm building a distributed storage system that works with different storage sizes. For instance, my storage devices have sizes of 50GB, 70GB, 150GB, 250GB, 1000GB, 5 storage systems in one system. My application will store any files to the storage system. Question: How can I build a distributed storage with the idea of data redundancy and fail-over to store documents, videos, any type of files at the same time ensuring that should one of any storage devices fail, there would be another copy of these files on another storage device. However, the concern is, 50GB of storage can only store this maximum number of files as compared to 70GB, 150GB etc. With one storage in mind, bringing 5 storage systems like a cloud storage, is there any logical way to distribute or store the files through my application? How do I ensure data redundancy through different storage sizes? Is there any algorithm to collate multiple blob files into a single file archive? What is the best solution for one cloud storage with multiple different storage sizes? I open this topic with the objective of discussing the best way to implement this idea, assuming simplicity, what are the issues of this implementation, performance measurements and discussion of the limitations.

  Read the article

• How can I perform sentiment analysis on extracted text from online sources?

  - by aniket69

  I'm working on extracting the sentiment from YouTube comments, blogs, news content, Facebook wall posts, and Twitter feeds. I'm looking for an automated way to do this: the two third-party solutions I've found have been AlchemyAPI and RapidMiner. Are these the best way to approach this project, or should I be using something else? Is there a more efficient way to approach sentiment analysis? What techniques have worked for you in a project like this?

  Read the article

• Mobile Application development - get hands on at UKOUG

  - by Grant Ronald

  Development of mobile solutions is one of the hottest topics in the IT market at the moment.  Forbes predicts that mobile application development with outstrip native PC development by 4-1 by 2015.  I'm therefor delighted to announce that the UKOUG and Oracle have synch'd up to provide a rolling 3 day hands-on Mobile development lab at the UKOUG conference this year. We're setting up a lab of 10 Mac machines in which you will be able to develop iOS on-device applications.  And the great thing is, if you want to develop for Android, its the same lab as well!  Just think, write once and deploy to iOS or Android.  We know places will be limited so we are going to be putting in place a first-come-first-served booking system.  Walk-ups will be allowed only if places are free. This is your chance to start skilling up on the hottest development initiative in years.

  Read the article

• How do I implement a "sliding out of / into" effect on a settings menu similar to that in Angry Birds?

  - by VictorB

  I'm trying to implement a settings menu component similar to that in Angry Birds - a button control that makes an options menu slide out of it and back into it when clicked on. I use scene2d.ui to build the UI components: a Button in a Table to implement the button control, a Table to implement the options menu, and a Stack to lay these out one on top of the other and at this moment I have the following behavior: When the user hits the button control for the first time, then the alpha of the table component is set to 1; When the user hits the button control the second time, then the alpha of the table component is set to 0; And so on. Any ideas how I can get the sliding out of and into effect on user clicks with libgdx? Similar to what Angry Birds provides. Maybe using the TweenEngine, actions, interpolations, combinations of these? Thanks in advance.

  Read the article

• OpenWorld Presentations and Anatomy of an RTF Template w/ files

  - by mdonohue

  For those who missed it ... or those who made it and couldn't get enough, check out the presentations delivered at OpenWorld: Overview and Roadmap The Reporting Platform for Oracle Applications Best Practices and even though it wasn't presented at OpenWorld an updated version of Anatomy of an RTF Template to include documented example files  (RTF template, Sub-Template and sample XML data) so you can re-use and play with the code directly.  Huge thanks to Tim and Hok-Min who did all the hard, original work on this example loaded with tips and tricks.  

  Read the article

• How to choose between Tell don't Ask and Command Query Separation?

  - by Dakotah North

  The principle Tell Don't Ask says: you should endeavor to tell objects what you want them to do; do not ask them questions about their state, make a decision, and then tell them what to do. The problem is that, as the caller, you should not be making decisions based on the state of the called object that result in you then changing the state of the object. The logic you are implementing is probably the called object’s responsibility, not yours. For you to make decisions outside the object violates its encapsulation. A simple example of "Tell, don't Ask" is Widget w = ...; if (w.getParent() != null) { Panel parent = w.getParent(); parent.remove(w); } and the tell version is ... Widget w = ...; w.removeFromParent(); But what if I need to know the result from the removeFromParent method? My first reaction was just to change the removeFromParent to return a boolean denoting if the parent was removed or not. But then I came across Command Query Separation Pattern which says NOT to do this. It states that every method should either be a command that performs an action, or a query that returns data to the caller, but not both. In other words, asking a question should not change the answer. More formally, methods should return a value only if they are referentially transparent and hence possess no side effects. Are these two really at odds with each other and how do I choose between the two? Do I go with the Pragmatic Programmer or Bertrand Meyer on this?

  Read the article

• Android Array Lag?

  - by Mike

  I am making a platform game for Android. It is sort of a tile based game. I added bullets and enemies with AI and a bunch of tile types. I created a simple map with no Enemies. Everything was running well and smooth until I shot a bunch of bullets randomly everywhere. A couple of hundreds of bullets later, the FPS lowered. I made a test to find out if the bullets were the problem so I made another simple map with just a tile to stand on and left it for a while. Minutes later, I played around with it a bit to check if the FPS changed and it didnt. I reloaded the same map and shot a lot of bullets. Minutes later, the FPS was visibly lower even after the number of bullets were zero. Points to note: Programmed FPS is 30 Tested on a Samsung Galaxy Y and Samsung Galaxy W Any tile, enemy, bullet that is off screen is not drawn to prevent lag Bullets collide with Tiles (if they dont collide with in 450 frames, they are removed from the array) I used List bullets = new ListArray(); I used bullets.add(new Bullet(x, y, params...)); I used for(...){ if(...){ bullets.remove(i); } } Code for bullet: private void drawBullets(Canvas canvas) { for (int i = 0; i < bullets.size(); i++) { Bullet b = bullets.get(i); b.update(canvas); //updates physics if (b.t > blm) { //if the bullet is past its expiry bullets.remove(i); i--; } else { if (svx((b.x)) > 0 && svx(b.x) < width && svy((b.y)) > 0 && svy(b.y) < height) { // if bullet is not off screen b.draw(canvas); // draw the bullet } } } } I tried searching for solutions and references but I have no luck. I'm guessing that the lag has something to do with the Array and the Bullets or Classes that I've loaded? I'm not sure! Someone please help! Thanks in advance! :)

  Read the article

• In Search Data Structure And Algorithm Project Title Based on Topic

  - by Salehin Suhaimi

  As the title says, my lecturer gave me a project that i needed to finish in 3 weeks before final semester exams. So i thought i will start now. The requirement is to "build a simple program that has GUI based on all the chapter that we've learned." But i got stuck on WHAT program should i build. Any idea a program that is related to this chapter i've learned? Any input will help. list, array list, linked list, vectors, stacks, Queues, ADT, Hashing, Binary Search Tree, AVL Tree, That's about all i can remember. Any idea where can i start looking?

  Read the article

• how to avoid or minimise use of check/conditional statement?

  - by Muneeb Nasir

  I have scenario, where i got stream and i need to check for some value. if i got my any new value i have to store it in any of data structure. well it seems very easy, i can place conditional statement if-else or can use contain method of set/map to check either received is new or not. but the problem is checking will effect my application performance, in stream i'll receive hundreds for value in second, if i start checking each and every value i received than for sure it effect performance. Any body can suggest me any mechanism or algorithm that solve my issue. either by bypassing checks or atleast minimize them?

  Read the article

< Previous Page | 773 774 775 776 777 778 779 780 781 782 783 784  | Next Page >