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Class loading problem

Posts: 13
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I am creating ant task "Javac" to compile a java file generated at runtime using ant-1.6.5.jar

A sample code snippet is as follows:-

Javac javac = new Javac();

javac.setProject (ANT_PROJECT);

Path path = new Path (ANT_PROJECT);

path.setPath (libdirPath_); // dependency jar needed for compilation of the generated java file.


javac.init ();

javac.setTarget ("1.5");

javac.setIncludejavaruntime (true);

javac.setDestdir (m_options.getClassesDir ());

javac.setEncoding (pnode.getEncoding ());

javac.setClasspath (path);

javac.setDebug (true);

javac.setSrcdir (srcPath);

javac.setOptimize (false);

try {

log. debug ("Compiling java source." + getJavaFile().getAbsolutePath());

javac.execute ();

log.debug ("Compiled java source.");


catch (BuildException e) {


Java file is compiled succesfully.

After that when I am trying to load the class using custom class loader in the following way:

private _JspTemplate tpl;


ReproClassLoader loader = (ReproClassLoader) Thread.currentThread ().getContextClassLoader ();

Class clazz = loader.loadClass (classQualified);

tpl = (_JspTemplate) clazz.newInstance ();

getting an NoClassDefFoundError.. com.anshinsoft.repro.jsp._JspTemplate

_JspTemplate is an abstract class and the generated java file is subclass of _JspTemplate.

My custom class loader "ReproClassLoader" basically URLClassLoader is used to load jar files at runtime.

when I am writing custom implementation of findClass () method in ReproClassLoader and Inside of the findClass ()

the class loader fetches the byte codes from local file system, then it is succesfully executed.

My concern is whether this is the only solution or not?

Can I do it in a better way? Please suggest.

Any help is highly appreciated

Thanks and Regards,

Ranch Hand
Posts: 2308
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This is a standard ant task.Why do you want to rewrite it ?
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