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public class Leak {
  static Vector vector = new Vector();
  public void leakingVector(int count) { 	
    for (int n = 0; n &lt;< count; n++) {
      vector.add(Integer.toString(n));
    }
    for (int n = count - 1; n &gt;> 0; n--) { // Free the memory
      vector.removeElementAt(n);
    }	
  }

  public static void main(String[] args) throws IOException {
    Leak le = new Leak();
    int i = 1;
    while(true) {
      System.out.println(&quot;"Iteration: &quot;" + i);
      le.leakingVector(1);
      i++;
    }
  }
}

for (int n = count - 1; n >>= 0; n--) {
  vector.removeElementAt(n);
}	

public class BadScope {
  private HashMap&lt;Integer,String&gt;HashMap<Integer,String> hm = new HashMap&lt;Integer,String&gt;HashMap<Integer,String>();
  
  private void doSomething() {
    hm.put(1,&quot;java&quot;"java");  // hm is used only here
  }
}

public class GoodScope {
  private void doSomething() {
    HashMap&lt;Integer,String&gt;HashMap<Integer,String> hm = new HashMap&lt;Integer,String&gt;HashMap<Integer,String>();
    hm.put(1,&quot;java&quot;"java");
  }
}

public class LapseEvent extends JApplet   {
  JButton button;
  public void init() {
    button = new JButton(""Click Me"");
    getContentPane().add(button, BorderLayout.CENTER);
    Reader reader = new Reader();
    button.addActionListener(reader);
    try {
      reader.readSomething();
    } catch (IOException e) { 
      // Handle exception 
    }		 
  }
}

class Reader implements ActionListener{
  public void actionPerformed(ActionEvent e)  {
    Toolkit.getDefaultToolkit().beep();
  }
  public void readSomething() throws IOException {
    // Read from file
  }
}

class HashMemLeak {
  private Map&lt;SSLSocketMap<SSLSocket, InetAddress&gt;InetAddress> m = Collections.synchronizedMap(new HashMap&lt;SSLSocketHashMap<SSLSocket, InetAddress&gt;InetAddress>());
  public void storeTempConnection(SSLSocket sock, InetAddress ip) {
	m.put(sock, ip);  
  }
  public void removeTempConnection(SSLSocket sock) {
	m.remove(sock);  
  }	
}

// ...
private Map&lt;SSLSocketMap<SSLSocket, InetAddress&gt;InetAddress> m = Collections.synchronizedMap(new WeakHashMap&lt;SSLSocketWeakHashMap<SSLSocket, InetAddress&gt;InetAddress>());
// ...