在Java中寻找ConcurrentHashSet吗？ - diwayou的专栏 - 博客频道 - CSDN.NET

在Java中寻找ConcurrentHashSet吗？ - diwayou的专栏 - 博客频道 - CSDN.NET

在Java中寻找ConcurrentHashSet吗？

分类：
Java

2011-05-11 09:37
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方法一：Collections.newSetFromMap(new ConcurrentHashMap<Object,Boolean>())

方法二：（引用自Apache Mina，位置org.apache.mina.util.ConcurrentHashSet）

 

package org.apache.mina.util;
import java.util.Collection;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
/**
 * A {@link ConcurrentHashMap}-backed {@link Set}.
 *
 * @author <a href="http://mina.apache.org" mce_href="http://mina.apache.org">Apache MINA Project</a>
 */
public class ConcurrentHashSet<E> extends MapBackedSet<E> {
    private static final long serialVersionUID = 8518578988740277828L;
    public ConcurrentHashSet() {
        super(new ConcurrentHashMap<E, Boolean>());
    }
    public ConcurrentHashSet(Collection<E> c) {
        super(new ConcurrentHashMap<E, Boolean>(), c);
    }
    @Override
    public boolean add(E o) {
        Boolean answer = ((ConcurrentMap<E, Boolean>) map).putIfAbsent(o, Boolean.TRUE);
        return answer == null;
    }
}

package org.apache.mina.util;<br /> import java.util.Collection;<br /> import java.util.Set;<br /> import java.util.concurrent.ConcurrentHashMap;<br /> import java.util.concurrent.ConcurrentMap;<br /> /**<br /> * A {@link ConcurrentHashMap}-backed {@link Set}.<br /> *<br /> * @author <a href="http://mina.apache.org" mce_href="http://mina.apache.org">Apache MINA Project</a><br /> */<br /> public class ConcurrentHashSet<E> extends MapBackedSet<E> {<br /> private static final long serialVersionUID = 8518578988740277828L;<br /> public ConcurrentHashSet() {<br /> super(new ConcurrentHashMap<E, Boolean>());<br /> }<br /> public ConcurrentHashSet(Collection<E> c) {<br /> super(new ConcurrentHashMap<E, Boolean>(), c);<br /> }<br /> @Override<br /> public boolean add(E o) {<br /> Boolean answer = ((ConcurrentMap<E, Boolean>) map).putIfAbsent(o, Boolean.TRUE);<br /> return answer == null;<br /> }<br /> }<br />