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？

方法一：Collections.newSetFromMap(new ConcurrentHashMap<Object,Boolean>())

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

 

[java] view plaincopyprint?

1. package org.apache.mina.util;  
2. import java.util.Collection;  
3. import java.util.Set;  
4. import java.util.concurrent.ConcurrentHashMap;  
5. import java.util.concurrent.ConcurrentMap;  
6. /** 
7.  * A {@link ConcurrentHashMap}-backed {@link Set}. 
8.  * 
9.  * @author <a href="http://mina.apache.org" mce_href="http://mina.apache.org">Apache MINA Project</a> 
10.  */  
11. public class ConcurrentHashSet<E> extends MapBackedSet<E> {  
12.     private static final long serialVersionUID = 8518578988740277828L;  
13.     public ConcurrentHashSet() {  
14.         super(new ConcurrentHashMap<E, Boolean>());  
15.     }  
16.     public ConcurrentHashSet(Collection<E> c) {  
17.         super(new ConcurrentHashMap<E, Boolean>(), c);  
18.     }  
19.     @Override  
20.     public boolean add(E o) {  
21.         Boolean answer = ((ConcurrentMap<E, Boolean>) map).putIfAbsent(o, Boolean.TRUE);  
22.         return answer == null;  
23.     }  
24. }  

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 />