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loading the inner classes using the custom class loaders

Posted on 2002-03-14
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Last Modified: 2010-03-31
i am trying to write my own loader for the classes i am using, i have a class with inner classes, how to load the inner classes and return the reference of the outer class?


hari

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Question by:bhksharma
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Venci75 earned 200 total points
ID: 6867660
import java.util.*;
import java.net.*;
import java.io.*;

public class CL extends ClassLoader {

  public class FilenamePattern implements FilenameFilter {
    String pattern;
    public FilenamePattern(String p) {pattern = p + "$";}
    public boolean accept(File dir, String name) { return name.startsWith(pattern);}
  }

  protected String path;
  public CL(String j) {
      path = j;
  }
  public File getPath(String name) {
      File file = new File(path);
      StringTokenizer tok = new StringTokenizer(name, ".");
      while (tok.hasMoreTokens()) {
          file = new File(file, tok.nextToken());
      }
      return file;
  }
  public String[] getFiles(String className) {
      File file = getPath(className);
      String[] result = file.getParentFile().list(new FilenamePattern(file.getName()));
      for (int i = 0; i < result.length; i++) {
          result[i] = result[i].substring(0, result[i].lastIndexOf(".class"));
      }
      return result;
  }
  public Class findClass(String name) {
      byte[] b = loadClassData(name);
      Class result =  defineClass(name, b, 0, b.length);
      String[] list = getFiles(name);
      String pkg = name.substring(0, name.lastIndexOf('.')+1);
      for (int i = 0; i < list.length; i++) {
          b = loadClassData(pkg + list[i]);
          defineClass(pkg + list[i], b, 0, b.length);
      }
      return result;
  }

  private byte[] loadClassData(String name) {
      // load the class data from the connection
      try {
          File file = getPath(name);
          file = new File(file.getParent(), file.getName() + ".class");
          InputStream is = new FileInputStream(file);
          int r;
          ByteArrayOutputStream os = new ByteArrayOutputStream();
          while ((r = is.read()) != -1)
              os.write(r);
          return os.toByteArray();
      } catch (Exception ex) {
          ex.printStackTrace();
      }
      return null;
  }
  public static void main(String args[]) throws Exception{
          // the path to your classes
          CL cl = new CL("c:/work/ClassLoser/classes/");
          Class test_class =  cl.findClass("class with inner class");
();
          Class test_inner_class = test_class.getClasses()[0];
          System.out.println(test_inner_class);
          System.out.println(test_inner_class.getClassLoader());
  }
}
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Expert Comment

by:Moondancer
ID: 6935148
Your question posted twice, experts are participating with you in both of them.
Moondancer - EE Moderator
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Expert Comment

by:Venci75
ID: 7901665
No comment has been added lately, so it's time to clean up this TA.
I will leave a recommendation in the Cleanup topic area that this question is:
Answered by: Venci75
Please leave any comments here within the next seven days.
 
PLEASE DO NOT ACCEPT THIS COMMENT AS AN ANSWER!
 
Venci75
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Expert Comment

by:Netminder
ID: 7962584
Per recommendation, force-accepted.

Netminder
EE Admin
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