///MemoryBlock.java
public class MemoryBlock {
  int id;
  int size;
  byte[] block;

  public MemoryBlock( int id, int size ) {
    this.id = id;
    this.size = size;
    block = new byte[size];
    System.out.println( "MemoryBlock created: "+this );
  }

  public String toString() {
    return "{id="+id+",size="+size+"}";
  }

  protected void finalize() {
    System.out.println( "MemoryBlock finalized: "+this );
  }

 }
//MyReference.java
import java.lang.ref.*;

public class MyReference extends SoftReference<MemoryBlock> {
  public MyReference( MemoryBlock referent ) {
    super( referent );
  }

  public MyReference( MemoryBlock referent, ReferenceQueue<MemoryBlock>q ) {
    super( referent, q );
  }

  public String toString() {
    return String.valueOf(get());
  }

 }

///MemoryTest1.java
import java.util.*;


 public class MemoryTest1 {
  public static void main( String[] args ) {
    ArrayList<MemoryBlock> blocks = new ArrayList<MemoryBlock>();
    int size = 65536;
    for ( int id=0; true; id++ ) {
      blocks.add( new MemoryBlock(id,size) );
      System.out.println( "blocks: "+blocks );
      size *= 2;
    }
  }

 }
///MemoryTest2.java
import java.lang.ref.*;

 import java.util.*;


 public class MemoryTest2 {
  public static void main( String[] args ) {
    ArrayList<MyReference> blocks = new ArrayList<MyReference>();
    int size = 65536;
    for ( int id=0; true; id++ ) {
      blocks.add( new MyReference(new MemoryBlock(id,size)) );
      System.out.println( "blocks: "+blocks );
      size *= 2;
    }
  }

 }

- posted by Pop @ 6:42 PM