How to run a java program in the JVM of an already running program?

As far as I know about JVM, each time we run a program a separate instance of JVM is created where the program runs. Correct me if I am wrong.
Is there any way for another program to execute itself in the same JVM?
Currently I am working on JFCUnit which is a tool used to automate swing applications. I am trying to automate JConsole.
If I open "JConsole.exe" through a program and then try to get the handles using JFCUnit, things are not working.
If I use JConsole.jar in JDK/lib and create a new instance of JConsole and then try to get the handles using JFCUnit, I am able to proceed with automation.
But here comes the problem :-
The application which needs to be automated through JConsole requires it to be started with few arguments, which is as follows:
%JDK_HOME%\bin\jconsole -J-Djava.class.path=%CLASSPATH% -J-Dcom.sun.management.jmxremote.ssl=false -J-Dcom.sun.management.jmxremote.authenticate=true -J-Djmx.remote.protocol.provider.pkgs=oracle.oc4j.admin.jmx.remote "service:jmx:rmi://localhost:23791"So this problem can be solved in two ways,
Either
1. JFCunit could be made to recognize the JConsole.exe which would be running is a different JVM.
OR
2. JConsole.jar to be used in a way so that it takes the required arguments, hereby an instance of JConsole would be created that too in the same JVM as that of the program.
I am more interested in the first solution as it would definitely be helpful in other projects as well.
Please let me know if any other solution is possible.
Any kinda solution is appreciated :)
Thanks in advance.

Give a look at Terracota.
http://www.terracottatech.com/

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<pre>
import java.util.Properties;
import java.io.FileInputStream;
import java.io.IOException;
import java.lang.reflect.Method;
import java.lang.reflect.InvocationTargetException;
import java.util.Enumeration;
import java.util.NoSuchElementException;
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private String iProg;
private String iArgs[];
public static void main(String args[])
new RunProg().main();
// first step is to start main program itself
private void main()
Properties properties = System.getProperties();
try
properties.load(new FileInputStream("RunProg.properties"));
catch(IOException e)
System.setProperties(properties);
int i = 0;
System.out.println("enter main, activeCount=" + Thread.activeCount());
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String program = properties.getProperty("Prog" + i);
if(program == null)
break;
StringTokenizer st = new StringTokenizer(program);
String[] args = new String[st.countTokens() - 1];
try
RunProg rp = (RunProg)this.clone();
rp.iProg = st.nextToken();
for(int j = 0; st.hasMoreTokens(); j++)
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catch(CloneNotSupportedException e)
System.out.println("prog" + i + "=" + program + ", can't start");
i++;
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public void run()
try
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Class p[] = new Class[1];
p[0] = String[].class;
Method m = c.getMethod("main", p);
Object o[] = new Object[1];
o[0] = iArgs;
m.invoke(null, o);
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System.out.println(iProg + "ClassNotFoundException");
catch(NoSuchMethodException e)
System.out.println(iProg + "NoSuchMethodException");
catch(InvocationTargetException e)
System.out.println(iProg + "NoSuchMethodException");
catch(IllegalAccessException e)
System.out.println(iProg + "NoSuchMethodException");
System.out.println(Thread.currentThread().getName() + ", ended");
System.out.println("exit run, activeCount=" + Thread.activeCount());
// setup SecurityManager to disable method System.exit()
public RunProg()
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// inner-class to disable method System.exit()
protected class mySecurityManager extends SecurityManager
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* inner-class to analyze StringTokenizer. This class is enhanced to check double Quotation marks
protected class StringTokenizer implements Enumeration
private int currentPosition;
private int maxPosition;
private String str;
private String delimiters;
private boolean retTokens;
* Constructs a string tokenizer for the specified string. All
* characters in the <code>delim</code> argument are the delimiters
* for separating tokens.
* <p>
* If the <code>returnTokens</code> flag is <code>true</code>, then
* the delimiter characters are also returned as tokens. Each
* delimiter is returned as a string of length one. If the flag is
* <code>false</code>, the delimiter characters are skipped and only
* serve as separators between tokens.
* @param str a string to be parsed.
* @param delim the delimiters.
* @param returnTokens flag indicating whether to return the delimiters
* as tokens.
public StringTokenizer(String str, String delim, boolean returnTokens)
currentPosition = 0;
this.str = str;
maxPosition = str.length();
delimiters = delim;
retTokens = returnTokens;
* Constructs a string tokenizer for the specified string. The
* characters in the <code>delim</code> argument are the delimiters
* for separating tokens. Delimiter characters themselves will not
* be treated as tokens.
* @param str a string to be parsed.
* @param delim the delimiters.
public StringTokenizer(String str, String delim)
this(str, delim, false);
* Constructs a string tokenizer for the specified string. The
* tokenizer uses the default delimiter set, which is
* <code>"\t\n\r\f"</code>: the space character, the tab
* character, the newline character, the carriage-return character,
* and the form-feed character. Delimiter characters themselves will
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* @param str a string to be parsed.
public StringTokenizer(String str)
this(str, " \t\n\r\f", false);
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protected void skipDelimiters()
while(!retTokens &&
(currentPosition < maxPosition) &&
(delimiters.indexOf(str.charAt(currentPosition)) >= 0))
currentPosition++;
* Tests if there are more tokens available from this tokenizer's string.
* If this method returns <tt>true</tt>, then a subsequent call to
* <tt>nextToken</tt> with no argument will successfully return a token.
* @return <code>true</code> if and only if there is at least one token
* in the string after the current position; <code>false</code>
* otherwise.
public boolean hasMoreTokens()
skipDelimiters();
return(currentPosition < maxPosition);
* Returns the next token from this string tokenizer.
* @return the next token from this string tokenizer.
* @exception NoSuchElementException if there are no more tokens in this
* tokenizer's string.
public String nextToken()
skipDelimiters();
if(currentPosition >= maxPosition)
throw new NoSuchElementException();
int start = currentPosition;
boolean inQuotation = false;
while((currentPosition < maxPosition) &&
(delimiters.indexOf(str.charAt(currentPosition)) < 0 || inQuotation))
if(str.charAt(currentPosition) == '"')
inQuotation = !inQuotation;
currentPosition++;
if(retTokens && (start == currentPosition) &&
(delimiters.indexOf(str.charAt(currentPosition)) >= 0))
currentPosition++;
String s = str.substring(start, currentPosition);
if(s.charAt(0) == '"')
s = s.substring(1);
if(s.charAt(s.length() - 1) == '"')
s = s.substring(0, s.length() - 1);
return s;
* Returns the next token in this string tokenizer's string. First,
* the set of characters considered to be delimiters by this
* <tt>StringTokenizer</tt> object is changed to be the characters in
* the string <tt>delim</tt>. Then the next token in the string
* after the current position is returned. The current position is
* advanced beyond the recognized token. The new delimiter set
* remains the default after this call.
* @param delim the new delimiters.
* @return the next token, after switching to the new delimiter set.
* @exception NoSuchElementException if there are no more tokens in this
* tokenizer's string.
public String nextToken(String delim)
delimiters = delim;
return nextToken();
* Returns the same value as the <code>hasMoreTokens</code>
* method. It exists so that this class can implement the
* <code>Enumeration</code> interface.
* @return <code>true</code> if there are more tokens;
* <code>false</code> otherwise.
* @see java.util.Enumeration
* @see java.util.StringTokenizer#hasMoreTokens()
public boolean hasMoreElements()
return hasMoreTokens();
* Returns the same value as the <code>nextToken</code> method,
* except that its declared return value is <code>Object</code> rather than
* <code>String</code>. It exists so that this class can implement the
* <code>Enumeration</code> interface.
* @return the next token in the string.
* @exception NoSuchElementException if there are no more tokens in this
* tokenizer's string.
* @see java.util.Enumeration
* @see java.util.StringTokenizer#nextToken()
public Object nextElement()
return nextToken();
* Calculates the number of times that this tokenizer's
* <code>nextToken</code> method can be called before it generates an
* exception. The current position is not advanced.
* @return the number of tokens remaining in the string using the current
* delimiter set.
* @see java.util.StringTokenizer#nextToken()
public int countTokens()
int count = 0;
int currpos = currentPosition;
while(currpos < maxPosition)
* This is just skipDelimiters(); but it does not affect
* currentPosition.
while(!retTokens &&
(currpos < maxPosition) &&
(delimiters.indexOf(str.charAt(currpos)) >= 0))
currpos++;
if(currpos >= maxPosition)
break;
int start = currpos;
boolean inQuotation = false;
while((currpos < maxPosition) &&
(delimiters.indexOf(str.charAt(currpos)) < 0 || inQuotation))
if(str.charAt(currpos) == '"')
inQuotation = !inQuotation;
currpos++;
if(retTokens && (start == currpos) &&
(delimiters.indexOf(str.charAt(currpos)) >= 0))
currpos++;
count++;
return count;
</pre>
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Prog1=GetEnv 47838 837489 892374 839274
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Last edited by mwillems (2015-04-21 00:03:43)

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