Search Results

Search found 35663 results on 1427 pages for 'embedded java'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 156/1427 | < Previous Page | 152 153 154 155 156 157 158 159 160 161 162 163  | Next Page >

  • How to debug Java code when using ANT script in Eclipse

    - by zengr
    Hi, I have a java class and I need to debug it (put breakpoints and continue using F6). I am using ANT script to init, build, deploy and run the code. I am using: <javac srcdir="${src.dir}" destdir="${classes.dir}" debug="true" debuglevel="lines,vars,source"> .......... </javac> But when I place the breakpoint in a line in my foo.java class and I run the ant script (the run part, Right Click on run--Debug As--Ant Build), Eclipse does not stop at that line of code. What am I missing out?!

    Read the article

  • How to demonstrate java multithreading visibility problems?

    - by Joe23
    If variables in Java are accessed from multiple threads, one must ensure that they are safely published. This usually means using synchronizedor volatile. I have got the impression, that some of my colleagues do not take this issue seriously, since they "never heard of volatile before and their programs have worked for years". So my question is: Can someone provide an example Java program/snippet, that reliably shows data visibility problems. I think running a program and seeing the unexpected NPE or stale variable value would help more, than just theoretic explanations, that cannot be demonstrated. Thanks a lot for your help!

    Read the article

  • Java Loop every minute.

    - by Robert
    I want to write a loop in Java that firs starts up and goes like this: while (!x){ //wait one minute or two //execute code } I want to do this so that it does not use up system resources. What is actually going on in the code is that it goes to a website and checks to see if something is done, if it is not done, it should wait another minute until it checks again, and when its done it just moves on. Is their anyway to do this in java? I googled it but didnt find anything. Thanks

    Read the article

  • High CPU usage when running several "java -version" in parallel

    - by Prateesh
    This is just out of curiosity to understand i have a small shell script for ((i = 0; i < 50; i++)) do java -version & done when i run this my CPU usage report by sar is as below 07:51:25 PM CPU %user %nice %system %iowait %steal %idle 07:51:30 PM all 6.98 0.00 1.75 1.00 0.00 90.27 07:51:31 PM all 43.00 0.00 12.00 0.00 0.00 45.00 07:51:32 PM all 86.28 0.00 13.72 0.00 0.00 0.00 07:51:33 PM all 5.25 0.00 1.75 0.50 0.00 92.50 As you can see, on the third line the CPU is at 100% My java version is 1.5.0_22-b03.

    Read the article

  • Rewrite arrays using collections

    - by owca
    I have a task, which I was able to do with the use of simplest methods - arrays. Now I'd like to go further and redo it using some more complicated java features like collections, but I've never used anything more complicated than 2d matrix. What should I look at and how to start with it. Should Tower become a Collection ? And here's the task : We have two classes - Tower and Block. Towers are built from Blocks. Ande here's sample code for testing: Block k1=new Block("yellow",1,5,4); Block k2=new Block("blue",2,2,6); Block k3=new Block("green",3,4,2); Block k4=new Block("yellow",1,5,4); Tower tower=new Tower(); tower.add(k1,k2,k3); "Added 3 blocks." System.out.println(tower); "block: green, base: 4cm x 3cm, thicknes: 2 cm block: blue, base: 6cm x 2cm, thicknes: 2 cm block: yellow, base: 5cm x 4cm, thicknes: 1 cm" tower.add(k2); "Tower already contains this block." tower.add(k4); "Added 1 block." System.out.println(tower); "block: green, base: 4cm x 3cm, thicknes: 2 cm block: blue, base: 6cm x 2cm, thicknes: 2 cm block: yellow, base: 5cm x 4cm, thicknes: 1 cm block: yellow, base: 5cm x 4cm, thicknes: 1 cm" tower.delete(k1); "Deleted 1 block" tower.delete(k1); "Block not in tower" System.out.println(tower); "block: blue, base: 6cm x 2cm, thicknes: 2 cm block: yellow, base: 5cm x 4cm, thicknes: 1 cm block: yellow, base: 5cm x 4cm, thicknes: 1 cm" Let's say I will treat Tower as a collection of blocks. How to perform search for specific block among whole collection ? Or should I use other interface ?

    Read the article

  • Java, filling arrays, and inheritance

    - by Arvanem
    Hi folks, I think I'm running into an inheritance conceptual wall with my Java arrays. I'm kind of new to Java so please tell me if I have things upside down. In essence, I want to do three things: Create a runnersArray with the attributes of my Runners class. Fill my runnersArray using my GenerateObjects method of my GenerateObjects class. Access the contents of my filled runnersArray in my Evaluating method of my Evaluating class. The problem seems to be that runnersArray is not visible to the methods in steps 2 and 3 above, but their classes (due to design reasons) cannot inherit or extend Runners class. Thanks in advance for any suggestions. Here are some code snippets showing what I'm trying to do: public class Runners extends Party { Runners[] runnersArray = new Runners[5]; } and public class GenerateObject extends /* certain parent class */ { public GenerateObject (int arrayNum) { runnersArray[arrayNum] = /* certain Runners attributes */; } } and public class Evaluating extends /*certain parent class*/ { public Evaluating (int arrayNum) { System.out.println(/* String cast attribute of runnersArray[arrayNum]*/; } }

    Read the article

  • Java: separating JAR versions

    - by Chris
    I'm developing a Java plugin for an existing Java program. The existing program uses a specific version of eclipse.uml2.* and my plugin does too. Unfortunately I need a newer version for my plugin. In order to run the plugin, I need to export it into a Jar file (with all jars packed). Then the program executes it. But somehow the new eclipse.uml2.* seem to interfere with the program - it crashes. Is there a way to "separate" both versions of the jar files?

    Read the article

  • Gradle java.util.logging.Logger output in unit tests

    - by Misha Koshelev
    Dear All: Sorry this is probably a very simple question. I am using gradle http://www.gradle.org/ for my development environment. It works quite well! I have written a simple unit test that uses HtmlUnit and my own package. For my own package, I use java.util.Logger. HtmlUnit seems to use commons logging: http://htmlunit.sourceforge.net/logging.html I would like to see console output of my logging messages from java.util.Logger However, it seems that even messages at the info level are not displayed in my Unit Test Results GUI (System.err link), although the HtmlUnit messages are all displayed. Please let me know if you have suggestions. Thank you! Misha

    Read the article

  • How to protect compiled Java classes?

    - by Registered User
    I know, many similar questions has been asked here. I am not asking if I can protect my compiled Java class - because obviously you will say 'no you can't'. I am asking what is the best known method of protecting Java classes against de-compiling? If you aware of any research or academic paper in this field please do let me know. Also if you have used some methods or software please share you experience? Any kind of information will be very useful. Thank you.

    Read the article

  • actionlistener not responding in java calculator

    - by tokee
    hi, please see calculator interface code below, from my beginners point of view the "1" should display when it's pressed but evidently i'm doing something wrong. any suggestiosn please? import java.awt.*; import javax.swing.*; import javax.swing.border.*; import java.awt.event.*; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JPanel; /** *A Class that operates as the framework for a calculator. *No calculations are performed in this section */ public class CalcFrame extends JPanel { private CalcEngine calc; private JFrame frame; private JTextField display; private JLabel status; /** * Constructor for objects of class GridLayoutExample */ //public CalcFrame(CalcEngine engine) //{ //frame.setVisible(true); // calc = engine; // makeFrame(); //} public CalcFrame() { makeFrame(); calc = new CalcEngine(); } class ButtonListener implements ActionListener { ButtonListener() { } public void actionPerformed(ActionEvent e) { if (e.getActionCommand().equals("1")) { System.out.println("1"); } } } /** * This allows you to quit the calculator. */ // Alows the class to quit. private void quit() { System.exit(0); } // Calls the dialog frame with the information about the project. private void showAbout() { JOptionPane.showMessageDialog(frame, "Declan Hodge and Tony O'Keefe Group Project", "About Calculator Group Project", JOptionPane.INFORMATION_MESSAGE); } // ---- swing stuff to build the frame and all its components ---- /** * The following creates a layout of the calculator frame. */ private void makeFrame() { frame = new JFrame("Group Project Calculator"); makeMenuBar(frame); JPanel contentPane = (JPanel)frame.getContentPane(); contentPane.setLayout(new BorderLayout(8, 8)); contentPane.setBorder(new EmptyBorder( 10, 10, 10, 10)); /** * Insert a text field */ display = new JTextField(8); contentPane.add(display, BorderLayout.NORTH); //Container contentPane = frame.getContentPane(); contentPane.setLayout(new GridLayout(4, 5)); JPanel buttonPanel = new JPanel(new GridLayout(4, 4)); contentPane.add(new JButton("9")); contentPane.add(new JButton("8")); contentPane.add(new JButton("7")); contentPane.add(new JButton("6")); contentPane.add(new JButton("5")); contentPane.add(new JButton("4")); contentPane.add(new JButton("3")); contentPane.add(new JButton("2")); contentPane.add(new JButton("1")); contentPane.add(new JButton("0")); contentPane.add(new JButton("+")); contentPane.add(new JButton("-")); contentPane.add(new JButton("/")); contentPane.add(new JButton("*")); contentPane.add(new JButton("=")); contentPane.add(new JButton("C")); contentPane.add(new JButton("CE")); contentPane.add(new JButton("%")); contentPane.add(new JButton("#")); //contentPane.add(buttonPanel, BorderLayout.CENTER); frame.pack(); frame.setVisible(true); } /** * Create the main frame's menu bar. * The frame that the menu bar should be added to. */ private void makeMenuBar(JFrame frame) { final int SHORTCUT_MASK = Toolkit.getDefaultToolkit().getMenuShortcutKeyMask(); JMenuBar menubar = new JMenuBar(); frame.setJMenuBar(menubar); JMenu menu; JMenuItem item; // create the File menu menu = new JMenu("File"); menubar.add(menu); // create the Quit menu with a shortcut "Q" key. item = new JMenuItem("Quit"); item.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_Q, SHORTCUT_MASK)); item.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { quit(); } }); menu.add(item); // Adds an about menu. menu = new JMenu("About"); menubar.add(menu); // Displays item = new JMenuItem("Calculator Project"); item.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { showAbout(); } }); menu.add(item); } }

    Read the article

  • ESRI frameworks: java vs javascript

    - by Luke
    I'm about to develop a web mapping application with ESRI Products like ArcGIS Server and Image Server. I can't find a good comparison between the Java Web ADF and the Javascript Framework. They're of course different because one is a full environment and the other is only client side but it's much more concise and the step to start is minimal. Another problem is that the Java Web ADF is not compatible with our current application server (JBoss 4.2.2) and require an old 4.0.2 version. Someone out there has experience that can help me? Many thanks.

    Read the article

  • groovy (java) error grabbing files

    - by senzacionale
    i can not grab files. I get: java.lang.RuntimeException: Error grabbing Grapes -- [unresolved dependency: org.apache.ivy#ivy;2.1.0: not found start of script which grab files import groovy.text.SimpleTemplateEngine import java.security.MessageDigest import org.apache.commons.cli.OptionBuilder import org.apache.commons.cli.Options import org.apache.commons.cli.PosixParser import org.apache.commons.io.FileUtils import org.apache.ivy.core.settings.IvySettings import org.apache.ivy.plugins.parser.m2.PomModuleDescriptorParser import org.apache.tools.ant.Project import org.apache.tools.ant.ProjectHelper import org.apache.tools.ant.types.Path import org.apache.commons.cli.HelpFormatter //First grab the grapes we need for the script and create a few beans to hold some values @Grab(group = 'org.apache.ant', module = 'ant', version = '1.7.1') @Grab(group = 'commons-io', module = 'commons-io', version = '1.4') @Grab(group = 'commons-cli', module = 'commons-cli', version = '1.2') @Grab(group = 'org.apache.ivy', module = 'ivy', version = '2.1.0')

    Read the article

  • Java - Highest, Lowest and Average

    - by Emily
    Right, so why does Java come up with this error: Exception in thread "main" java.lang.Error: Unresolved compilation problem: Type mismatch: cannot convert from double to int at rainfall.main(rainfall.java:38) From this: public class rainfall { /** * @param args */ public static void main(String[] args) { int[] numgroup; numgroup = new int [12]; ConsoleReader console = new ConsoleReader(); int highest; int lowest; int index; int tempVal; int minMonth; int minIndex; int maxMonth; int maxIndex; System.out.println("Welcome to Rainfall"); // Input (index now 0-based) for(index = 0; index < 12; index = index + 1) { System.out.println("Please enter the rainfall for month " + index + 1); tempVal = console.readInt(); while (tempVal100 || tempVal<0) { System.out.println("The rating must be within 0...100. Try again"); tempVal = console.readInt(); } numgroup[index] = tempVal; } lowest = numgroup[0]; highest = numgroup[0]; int total = 0.0; // Loop over data (using 1 loop) for(index = 0; index < 12; index = index + 1) { int curr = numgroup[index]; if (curr < lowest) { lowest = curr; minIndex = index; } if (curr highest) { highest = curr; maxIndex = index; } total += curr; } float avg = (float)total / numgroup.length; System.out.println("The average monthly rainfall was " + avg); // +1 to go from 0-based index to 1-based month System.out.println("The lowest monthly rainfall was month " + minIndex + 1); System.out.println("The highest monthly rainfall was month " + maxIndex + 1); System.out.println("Thank you for using Rainfall"); } private static ConsoleReader ConsoleReader() { return null; } }

    Read the article

  • 'SImple' 2 class Java calculator doesn't accept inputs or do calculations

    - by Tony O'Keeffe
    Hi, I'm trying to get a two class java calculator working (new to java) to work but so far i'm having no success. the two classes are outlined below, calcFrame is for the interface and calEngine should do the actual calculations but i can't get them to talk to one another. i'd really appreciate any assistance on same. Thanks. CalcFrame Code - import java.awt.; import javax.swing.; import javax.swing.border.; import java.awt.event.; /** *A Class that operates as the framework for a calculator. *No calculations are performed in this section */ public class CalcFrame implements ActionListener { private CalcEngine calc; private JFrame frame; private JTextField display; private JLabel status; /** * Constructor for objects of class GridLayoutExample */ public CalcFrame() { makeFrame(); //calc = engine; } /** * This allows you to quit the calculator. */ // Alows the class to quit. private void quit() { System.exit(0); } // Calls the dialog frame with the information about the project. private void showAbout() { JOptionPane.showMessageDialog(frame, "Group Project", "About Calculator Group Project", JOptionPane.INFORMATION_MESSAGE); } private void makeFrame() { frame = new JFrame("Group Project Calculator"); makeMenuBar(frame); JPanel contentPane = (JPanel)frame.getContentPane(); contentPane.setLayout(new BorderLayout(8, 8)); contentPane.setBorder(new EmptyBorder( 10, 10, 10, 10)); /** * Insert a text field */ display = new JTextField(); contentPane.add(display, BorderLayout.NORTH); //Container contentPane = frame.getContentPane(); contentPane.setLayout(new GridLayout(4, 4)); JPanel buttonPanel = new JPanel(new GridLayout(4, 4)); contentPane.add(new JButton("1")); contentPane.add(new JButton("2")); contentPane.add(new JButton("3")); contentPane.add(new JButton("4")); contentPane.add(new JButton("5")); contentPane.add(new JButton("6")); contentPane.add(new JButton("7")); contentPane.add(new JButton("8")); contentPane.add(new JButton("9")); contentPane.add(new JButton("0")); contentPane.add(new JButton("+")); contentPane.add(new JButton("-")); contentPane.add(new JButton("/")); contentPane.add(new JButton("*")); contentPane.add(new JButton("=")); contentPane.add(new JButton("C")); contentPane.add(buttonPanel, BorderLayout.CENTER); //status = new JLabel(calc.getAuthor()); //contentPane.add(status, BorderLayout.SOUTH); frame.pack(); frame.setVisible(true); } /** * Create the main frame's menu bar. * The frame that the menu bar should be added to. */ private void makeMenuBar(JFrame frame) { final int SHORTCUT_MASK = Toolkit.getDefaultToolkit().getMenuShortcutKeyMask(); JMenuBar menubar = new JMenuBar(); frame.setJMenuBar(menubar); JMenu menu; JMenuItem item; // create the File menu menu = new JMenu("File"); menubar.add(menu); // create the Quit menu with a shortcut "Q" key. item = new JMenuItem("Quit"); item.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_Q, SHORTCUT_MASK)); item.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { quit(); } }); menu.add(item); // Adds an about menu. menu = new JMenu("About"); menubar.add(menu); // Displays item = new JMenuItem("Calculator Project"); item.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { showAbout(); } }); menu.add(item); } /** * An interface action has been performed. * Find out what it was and handle it. * @param event The event that has occured. */ public void actionPerformed(ActionEvent event) { String command = event.getActionCommand(); if(command.equals("0") || command.equals("1") || command.equals("2") || command.equals("3") || command.equals("4") || command.equals("5") || command.equals("6") || command.equals("7") || command.equals("8") || command.equals("9")) { int number = Integer.parseInt(command); calc.numberPressed(number); } else if(command.equals("+")) { calc.plus(); } else if(command.equals("-")) { calc.minus(); } else if(command.equals("=")) { calc.equals(); } else if(command.equals("C")) { calc.clear(); } else if(command.equals("?")) { } // else unknown command. redisplay(); } /** * Update the interface display to show the current value of the * calculator. */ private void redisplay() { display.setText("" + calc.getDisplayValue()); } /** * Toggle the info display in the calculator's status area between the * author and version information. */ } CalcEngine - public class CalcEngine { // The calculator's state is maintained in three fields: // buildingDisplayValue, haveLeftOperand, and lastOperator. // The current value (to be) shown in the display. private int displayValue; // The value of an existing left operand. private int leftOperand; /** * Create a CalcEngine. */ public CalcEngine() { clear(); } public int getDisplayValue() { return displayValue; } /** * A number button was pressed. * Either start a new operand, or incorporate this number as * the least significant digit of an existing one. * @param number The number pressed on the calculator. */ public void numberPressed(int number) { if(buildingDisplayValue) { // Incorporate this digit. displayValue = displayValue*10 + number; } else { // Start building a new number. displayValue = number; buildingDisplayValue = true; } } /** * The 'plus' button was pressed. */ public void plus() { applyOperator('+'); } /** * The 'minus' button was pressed. */ public void minus() { applyOperator('-'); } /** * The '=' button was pressed. */ public void equals() { // This should completes the building of a second operand, // so ensure that we really have a left operand, an operator // and a right operand. if(haveLeftOperand && lastOperator != '?' && buildingDisplayValue) { calculateResult(); lastOperator = '?'; buildingDisplayValue = false; } else { keySequenceError(); } } /** * The 'C' (clear) button was pressed. * Reset everything to a starting state. */ public void clear() { lastOperator = '?'; haveLeftOperand = false; buildingDisplayValue = false; displayValue = 0; } /** * @return The title of this calculation engine. */ public String getTitle() { return "Java Calculator"; } /** * @return The author of this engine. */ public String getAuthor() { return "David J. Barnes and Michael Kolling"; } /** * @return The version number of this engine. */ public String getVersion() { return "Version 1.0"; } /** * Combine leftOperand, lastOperator, and the * current display value. * The result becomes both the leftOperand and * the new display value. */ private void calculateResult() { switch(lastOperator) { case '+': displayValue = leftOperand + displayValue; haveLeftOperand = true; leftOperand = displayValue; break; case '-': displayValue = leftOperand - displayValue; haveLeftOperand = true; leftOperand = displayValue; break; default: keySequenceError(); break; } } /** * Apply an operator. * @param operator The operator to apply. */ private void applyOperator(char operator) { // If we are not in the process of building a new operand // then it is an error, unless we have just calculated a // result using '='. if(!buildingDisplayValue && !(haveLeftOperand && lastOperator == '?')) { keySequenceError(); return; } if(lastOperator != '?') { // First apply the previous operator. calculateResult(); } else { // The displayValue now becomes the left operand of this // new operator. haveLeftOperand = true; leftOperand = displayValue; } lastOperator = operator; buildingDisplayValue = false; } /** * Report an error in the sequence of keys that was pressed. */ private void keySequenceError() { System.out.println("A key sequence error has occurred."); // Reset everything. clear(); } }

    Read the article

  • [java] Efficiency of while(true) ServerSocket Listen

    - by Submerged
    I am wondering if a typical while(true) ServerSocket listen loop takes an entire core to wait and accept a client connection (Even when implementing runnable and using Thread .start()) I am implementing a type of distributed computing cluster and each computer needs every core it has for computation. A Master node needs to communicate with these computers (invoking static methods that modify the algorithm's functioning). The reason I need to use sockets is due to the cross platform / cross language capabilities. In some cases, PHP will be invoking these java static methods. I used a java profiler (YourKit) and I can see my running ServerSocket listen thread and it never sleeps and it's always running. Is there a better approach to do what I want? Or, will the performance hit be negligible? Please, feel free to offer any suggestion if you can think of a better way (I've tried RMI, but it isn't supported cross-language. Thanks everyone

    Read the article

  • Java resource as file

    - by Martin Riedel
    Is there a way in Java to construct a File instance on a resource retrieved from a jar through the classloader? My application uses some files from the jar (default) or from a filesystem directory specified at runtime (user input). I'm looking for a consistent way of a) loading these files as a stream b) listing the files in the user-defined directory or the directory in the jar respectively Edit: Apparently, the ideal approach would be to stay away from java.io.File altogether. Is there a way to load a directory from the classpath and list its contents (files/entities contained in it)?

    Read the article

  • Java 'Prototype' pattern - new vs clone vs class.newInstance

    - by Guillaume
    In my project there are some 'Prototype' factories that create instances by cloning a final private instance. The author of those factories says that this pattern provides better performance than calling 'new' operator. Using google to get some clues about that, I've found nothing really relevant about that. Here is a small excerpt found in a javdoc from an unknown project javdoc from an unknown project Sadly, clone() is rather slower than calling new. However it is a lot faster than calling java.lang.Class.newInstance(), and somewhat faster than rolling our own "cloner" method. For me it's looking like an old best practice of the java 1.1 time. Does someone know more about this ? Is this a good practice to use that with 'modern' jvm ?

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 152 153 154 155 156 157 158 159 160 161 162 163  | Next Page >