System.out.println(...) causes applet to throw OutOfMemoryError exception

Hi all,
I've created an applet with a very barebones method in it, that is causing an OutOfMemoryError when run for approx 2 minutes.
Here is the code...
import javax.swing.JApplet;
public class BridgeMapApplet extends JApplet
public void start()
          Thread t = new Thread(){
          public void run() {
               String response = "<bridgeMapResponse><bridges><bridge><macAddress>00:07:D5:01:3B:ED</macAddress><parentMacAddress>00:00:00:00:00:00</parentMacAddress><ipAddress>192.168.254.157</ipAddress><card></card><secondCard></secondCard><wdsName></wdsName><cfgFileTag></cfgFileTag><rssi>0</rssi><stpStatus></stpStatus><children><bridge><macAddress>00:07:D5:01:3C:19</macAddress><parentMacAddress>00:07:D5:01:3B:ED</parentMacAddress><ipAddress>192.168.254.166</ipAddress><card></card><secondCard></secondCard><wdsName></wdsName><cfgFileTag></cfgFileTag><rssi>73</rssi><stpStatus></stpStatus><children><bridge><macAddress>00:07:D5:01:45:BE</macAddress><parentMacAddress>00:07:D5:01:3C:19</parentMacAddress><ipAddress>192.168.254.152</ipAddress><card></card><secondCard></secondCard><wdsName></wdsName><cfgFileTag></cfgFileTag><rssi>80</rssi><stpStatus></stpStatus><children><bridge><macAddress>00:07:D5:01:47:12</macAddress><parentMacAddress>00:07:D5:01:45:BE</parentMacAddress><ipAddress>192.168.254.153</ipAddress><card></card><secondCard></secondCard><wdsName></wdsName><cfgFileTag></cfgFileTag><rssi>0</rssi><stpStatus></stpStatus><description></description><deviceStatus>New</deviceStatus></bridge><bridge><macAddress>00:07:D5:01:46:78</macAddress><parentMacAddress>00:07:D5:01:45:BE</parentMacAddress><ipAddress>192.168.254.162</ipAddress><card></card><secondCard></secondCard><wdsName></wdsName><cfgFileTag></cfgFileTag><rssi>0</rssi><stpStatus></stpStatus><description></description><deviceStatus>New</deviceStatus></bridge><bridge><macAddress>00:07:D5:01:3D:B9</macAddress><parentMacAddress>00:07:D5:01:45:BE</parentMacAddress><ipAddress>192.168.254.154</ipAddress><card></card><secondCard></secondCard><wdsName></wdsName><cfgFileTag></cfgFileTag><rssi>0</rssi><stpStatus></stpStatus><description></description><deviceStatus>New</deviceStatus></bridge></children><description></description><deviceStatus>New</deviceStatus></bridge></children><description></description><deviceStatus>New</deviceStatus></bridge><bridge><macAddress>00:07:D5:01:46:94</macAddress><parentMacAddress>00:07:D5:01:3B:ED</parentMacAddress><ipAddress>192.168.254.165</ipAddress><card></card><secondCard></secondCard><wdsName></wdsName><cfgFileTag></cfgFileTag><rssi>63</rssi><stpStatus></stpStatus><description></description><deviceStatus>New</deviceStatus></bridge><bridge><macAddress>00:07:D5:01:3D:D3</macAddress><parentMacAddress>00:07:D5:01:3B:ED</parentMacAddress>ipAddress>192.168.254.168</ipAddress><card></card><secondCard></secondCard><wdsName></wdsName><cfgFileTag></cfgFileTag><rssi>78</rssi><stpStatus></stpStatus><children><bridge><macAddress>00:07:D5:01:46:7A</macAddress><parentMacAddress>00:07:D5:01:3D:D3</parentMacAddress><ipAddress>192.168.254.163</ipAddress><card></card><secondCard></secondCard><wdsName></wdsName><cfgFileTag></cfgFileTag><rssi>100</rssi><stpStatus></stpStatus><description></description><deviceStatus>New</deviceStatus></bridge><bridge><macAddress>00:07:D5:01:3D:D5</macAddress><parentMacAddress>00:07:D5:01:3D:D3</parentMacAddress><ipAddress>192.168.254.161</ipAddress><card></card><secondCard></secondCard><wdsName></wdsName><cfgFileTag></cfgFileTag><rssi>99</rssi><stpStatus></stpStatus><description></description><deviceStatus>New</deviceStatus></bridge><bridge><macAddress>00:07:D5:01:3D:6F</macAddress><parentMacAddress>00:07:D5:01:3D:D3</parentMacAddress><ipAddress>192.168.254.164</ipAddress><card></card><secondCard></secondCard><wdsName></wdsName><cfgFileTag></cfgFileTag><rssi>100</rssi><stpStatus></stpStatus><description></description><deviceStatus>New</deviceStatus></bridge><bridge><macAddress>00:07:D5:01:3D:81</macAddress><parentMacAddress>00:07:D5:01:3D:D3</parentMacAddress><ipAddress>192.168.254.167</ipAddress><card></card><secondCard></secondCard><wdsName></wdsName><cfgFileTag></cfgFileTag><rssi>100</rssi><stpStatus></stpStatus><description></description><deviceStatus>New</deviceStatus></bridge></children><description></description><deviceStatus>New</deviceStatus></bridge></children><description></description><deviceStatus>New</deviceStatus></bridge></bridges><lastUpdate>2009-12-21T19:45:25.375Z</lastUpdate></bridgeMapResponse>";
while(true) {
                    System.out.println(response);
                    try{
                         Thread.sleep(10);
                    }catch(InterruptedException ie){}
               } //end while
          } //end run
          }; //end thread
          t.start();
} // end of start()
} // end of applet
When I connect to the process with a java debugger, i get the following output after a couple minutes...
C:\eclipse\workspace\applet>jdb -attach 2502
Set uncaught java.lang.Throwable
Set deferred uncaught java.lang.Throwable
Initializing jdb ...
>
Exception occurred: java.lang.OutOfMemoryError (uncaught)"thread=traceMsgQueueTh
read", com.sun.deploy.util.Trace.firePrintlnEvent(), line=-1 bci=58
traceMsgQueueThread[1]
===================================================================
I know this is a very frequent thread execution, but this was to speed up the replication of a bug that occurs after a few hours.
Regardless of how low the Thread.sleep() interval is, why would this cause an OutOfMemoryError?
thank you!!

When posting code, code snippets, HTML/XML or input/output, please use the code tags. The code tags help retain the indentation and formatting of the sample. To use the code tags, select the sample and click the CODE button.
As an aside, what on earth is the use of dumping output to the console in an applet?
My initial thought as to how prevent the OOME when dumping loads to the Java Console is - don't dump loads to it. The Java Console is effectively useless to the average end-user, either way. The Java Console is not easy to open, for an applet that makes it through the init() successfully.

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Here is my code
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pl.java:437)
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I have jave 7 I'm trying underscore option in String. as String strNum = "1000_000";System.out.println("..abc..." Integer.parseInt(strNum)); but getting error. could you please help in this?

Hi,
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what is your actual question here?
bye
TPD

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Hi
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Disable or restrict System.out.println() statements on client side

Hi All,
This might be a stupid question, but i am still going ahead and asking the question.
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Hi All,
This might be a stupid question, but i am still going
ahead and asking the question.
Is there a way to disable or restrict
System.out.println() statements in applet code from
executing on the client side by using settings in
proxy server or firewall or other security settings.
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System.out.println() problem

When I use operator + for concatenate the following Strings
md.getDriverName() + md.getDriverVersion()
as follow in a try block:
try {
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md = con.getMetaData();
System.out.println(md.getDriverName().+md.getDriverVersion());
when I have tried run java -cp postgresql.jar errors message appers :
Exception in thread "main" java.lang.NoClassDefFoundError: while resolving class: conx
at java.lang.VMClassLoader.transformException(java.lang.Class, java.lang.Throwable) (/usr/lib/libgcj.so.6.0.0)
at java.lang.VMClassLoader.resolveClass(java.lang.Class) (/usr/lib/libgcj.so.6.0.0)
at java.lang.Class.initializeClass() (/usr/lib/libgcj.so.6.0.0)
at java.lang.Class.forName(java.lang.String, boolean, java.lang.ClassLoader) (/usr/lib/libgcj.so.6.0.0)
at gnu.java.lang.MainThread.run() (/usr/lib/libgcj.so.6.0.0)
Caused by: java.lang.ClassNotFoundException: java.lang.StringBuilder not found in gnu.gcj.runtime.SystemClassLoader{urls=[file:postgresql.jar,file:./], parent=gnu.gcj.runtime.ExtensionClassLoader{urls=[], parent=null}}
at java.net.URLClassLoader.findClass(java.lang.String) (/usr/lib/libgcj.so.6.0.0)
at java.lang.ClassLoader.loadClass(java.lang.String, boolean) (/usr/lib/libgcj.so.6.0.0)
at java.lang.ClassLoader.loadClass(java.lang.String) (/usr/lib/libgcj.so.6.0.0)
at java.lang.Class.forName(java.lang.String, boolean, java.lang.ClassLoader) (/usr/lib/libgcj.so.6.0.0)
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Caused by: java.lang.ClassNotFoundException: java.lang.StringBuilder not found in
gnu.gcj.runtime.SystemClassLoader{urls=[file:postgresql.jar,file:./],
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System.out.println ....syntax error?

Hi,
I am workin on my first java program here...and althought my classes compile just fine I can't manage to get what I want to appear on the screen on Button action....
Clicking on cost should trigger the appearance of the total cost...but nothing happens.
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import java.awt.event.*;
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import java.util.*;
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int c1;
int p1;
int price;
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add(ChoiceCourse);
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while (i<c.length)
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add(new Label("Number of participants for the course selected : "));
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ChoicePeople.addItemListener(this);
cb1 = new Checkbox ("Full-Time");
add(cb1);
cb2 = new Checkbox ("Part-Time");
add (cb2);
cb3 = new Checkbox ("Concessions");
add (cb3);
b1 = new Button ("Cost");
add (b1);
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Thanks for the guidance and the explanations. I've improved my code according to your recommendations (1, 2 &3) and it compiles just fine.
However, the println still doesn't work...but there is improvement:
When I run my applet using the AppletViewer at the very end I get a log of what happened...and it's now showing:
"D:\JBuilder8\jdk1.4\bin\appletviewer.exe Booking.html
total cost of your selection is: �0"
Which means that the println is being called but is not printing where it should be (on my screen)....the other problem is that it is obviously not properly calculating the total cost since it shouldn't be �0.
Here is my new (improved) code, and below is the code for the Courses class (which does some of the calculation):
import java.awt.*;
import java.awt.event.*;
import java.applet.*;
import java.util.*;
public class Booking extends Applet implements ItemListener,ActionListener
String[][] c = { {"French Language","250","130","70"}, {"Painting","270","140","70"}, {"Yoga","250","130","70"} };
Courses courses_list = new Courses(c);
Choice ChoiceCourse;
Choice ChoicePeople;
Checkbox cb1, cb2, cb3;
boolean fulltime = false;
boolean parttime = false;
boolean concessions = false;
Button b1;
int c1;
int p1;
int price;
public void init()
add(new Label("Courses available for booking : "));
ChoiceCourse = new Choice();
add(ChoiceCourse);
//the following populates the ChoiceCourse dropDown Menu with the Courses'Titles
int i=0;
while (i<c.length)
    ChoiceCourse.addItem(courses_list.getTitle(i));
    i++;
ChoiceCourse.addItemListener(this);
add(new Label("Number of participants for the course selected : "));
ChoicePeople = new Choice();
add(ChoicePeople);
//the following populates the ChoicePeople dropDown Menu with "numbers" from 1 to 10
int j=1;
while (j<11)
    ChoicePeople.addItem(new Integer(j).toString());
    j++;
ChoicePeople.addItemListener(this);
cb1 = new Checkbox ("Full-Time");
add(cb1);
cb2 = new Checkbox ("Part-Time");
add (cb2);
cb3 = new Checkbox ("Concessions");
add (cb3);
b1 = new Button ("Cost");
add (b1);
b1.addActionListener(this);
public void itemStateChanged(ItemEvent e)
   if (e.getSource().equals (ChoiceCourse)) //should this be == or .equals? it doesn't work either way but compiles
     String c2 = (String) e.getItem(); // When ChoiceCourse is modified
     if (c2.equals ("French Language"))
       c1 = 0;
     if (c2.equals ("Painting"))
       c1 = 1;
     else
       c1 = 2;
   if (e.getSource().equals (ChoicePeople)) //should this be == or .equals?it doesn't work either way but compiles
     String p2 = (String) e.getItem(); // When ChoicePeople is modified
     p1=Integer.parseInt(p2);       // converts the String into an integer
public void actionPerformed(ActionEvent e)
    if ( e.getActionCommand().equals ("Cost") )
      fulltime = cb1.getState();
      parttime = cb2.getState();
      concessions = cb3.getState();
      if (fulltime)
        price = 1;
      if (parttime)
        price = 2;
      else
        price = 3;
      int mode = Integer.parseInt(c[c1][price]);
      System.out.println("total cost of your selection is: �" + courses_list.getCost(p1,mode));
class Courses
import java.util.*;
public class Courses
private String[][] Listing = new String[3][4]; //create array 3 rows * 4 columns
Courses(String[][] c)
   this.Listing=c;
int i;
int j;
int p;
int price;
int people;
int cost;
String t;
String p1;
String getTitle(int i) //return Course Title
   t=Listing[0];
return t;
int getPrice(int i, int j) //return Price (Full-Time, Part-Time, Concessions)
p1=Listing[i][j];
p=Integer.parseInt(p1);
return p;
int getCost(int pe, int pp)
pe=price;
pp=people;
cost=pe*pp;
return cost;

Unicode in System.out.println()

Hello All,
Can somebody help me figure out why the following code prints '?'.
import java.io.*;
class Test {
public static void main(String args[]) throws Exception {
System.out.println("\u0080");
PrintWriter aPrintWriter = new PrintWriter(System.out);
aPrintWriter.write("\u0080");
aPrintWriter.flush();
What needs to be done to get the actual character that is expected.
Nischal

Can somebody help me figure out why the following code
prints '?'. It's because of the character set of your console.
System.out is a PrintStream which works with bytes not with characters.
You can use
OutputStreamWriter osw = new OutputStreamWriter(System.out, "ISO-8859-1")
PrintWriter myPrintWriter = new PrintWriter( osw);
myPrintWriter.write( "\u0080");of course you'll have to use the character set your console uses.

Why System.out.println not PrintStream.println ?

Hi, just a beginner question
I just wonder why should we use System.out.println, not PrintStream.println ?
the field out in the System class is the instance of PrintStream class, isn't it?
So why don't we just use the PrintStream class directly?
Thanks..
Edited by: riff_almighty on Oct 27, 2007 3:27 AM

According to the api:
A PrintStream adds functionality to another output stream, namely the ability to print representations of various data values conveniently. Two other features are provided as well. Unlike other output streams, a PrintStream never throws an IOException; instead, exceptional situations merely set an internal flag that can be tested via the checkError method. Optionally, a PrintStream can be created so as to flush automatically; this means that the flush method is automatically invoked after a byte array is written, one of the println methods is invoked, or a newline character or byte ('\n') is written.
So there is nowhere mentioned about the PrintStream associated with the user console. System.out is the one instance of PrintStream which is associated with the console...
Also println() is not a static method and cant be called upon the class...
Edited by: VijayBabu on Oct 27, 2007 12:51 AM

System.out.println(...) causes applet to throw OutOfMemoryError exception

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