Name: avC70361 Date: 12/05/97



  The java.util.TreeMap class fails to be serialized despite of implementing the
java.io.Serializable interface because unexpected exception
NotSerializableException for class java.util.TreeMap$Entry is thrown.

Here is the test demonstrating the bug
----------TreeMapTest.java------
import java.util.TreeMap;
import java.io.IOException;
import java.io.ByteArrayOutputStream;
import java.io.ObjectOutputStream;

public class TreeMapTest {

  public static void main(String args[]) {

    ObjectOutputStream stream = null;

    try {

      stream = new ObjectOutputStream(
        new ByteArrayOutputStream()
      );

    } catch(IOException e) {
      System.out.println("Unexpected exception : " + e);
      System.exit(1);
    }

    try {

      TreeMap map = new TreeMap();
      map.put("key", "entry");

      stream.writeObject(map);

    } catch(IOException e) {
      System.out.println("Unexpected exception : " + e);
    }

  }

}
-------The test output----------
#>java TreeMapTest
Unexpected exception : java.io.NotSerializableException: java.util.TreeMap$Entry
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