Map的keySet方法序列化BUG问题及其解决方法

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Map的keySet在进行序列化时，报错：java.io.NotSerializableException: java.util.HashMap$KeySet。这个异常可以再oracle的官网：http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4756277中查到原因，为了方便日后测试序列化问题，给出序列化的测试类。
序列化的测试类:

import java.io.ByteArrayOutputStream;import java.io.ObjectOutputStream;import java.util.HashMap;import java.util.Map;/** * Created by IntelliJ IDEA. * User: dragon * Date: 12-8-20 * Time: 上午11:04 * 序列化测试类 */public class MapCollectionSerializeTest {    private static void trySerialize (Object o) {        try {            ObjectOutputStream stream                = new ObjectOutputStream(new ByteArrayOutputStream());            System.out.print("Trying to serialize " + o + "...");            stream.writeObject(o);            stream.flush();            System.out.println("done");        }        catch (Exception e) {            System.out.print("failed: ");            e.printStackTrace();        }    }    // ----------------------------------------------------------------------    // Entry point    public static void main (String[] args) {        Map map = new HashMap();        map.put("one", "one");        map.put("two", "two");        map.put("three", "three");        System.out.println("keySet():");        trySerialize(map.keySet());        System.out.println("entrySet():");        trySerialize(map.entrySet());        System.out.println("values():");        trySerialize(map.values());    }}

解决方法：

Set set = new HashSet(map.keySet());