java Collections学习

java集合的同步：（还需深入）

Collections.synchronizedList(List)

List list = Collections.synchronizedList(new ArrayList()); … … Synchronized(list){      Iterator i = list.iterator();//Must be in synchronized block      While(i.hasNext())           foo(i.next()); }

Collections.synchronizedSet(Set)

Set s = Collections.synchronizedSet(new HashSet());       ...   synchronized(s) {       Iterator i = s.iterator(); // Must be in the synchronized block       while (i.hasNext())           foo(i.next());   }

SortedSet s = Collections.synchronizedSortedSet(new HashSortedSet());       ...   synchronized(s) {       Iterator i = s.iterator(); // Must be in the synchronized block       while (i.hasNext())           foo(i.next());   }

SortedSet s = Collections.synchronizedSortedSet(new HashSortedSet());   SortedSet s2 = s.headSet(foo);       ...   synchronized(s) {  // Note: s, not s2!!!       Iterator i = s2.iterator(); // Must be in the synchronized block       while (i.hasNext())           foo(i.next());   }

Collections.synchronizedMap(Map)

Map m = Collections.synchronizedMap(new HashMap());       ...   Set s = m.keySet();  // Needn't be in synchronized block       ...   synchronized(m) {  // Synchronizing on m, not s!       Iterator i = s.iterator(); // Must be in synchronized block       while (i.hasNext())           foo(i.next());   }

SortedMap m = Collections.synchronizedSortedMap(new HashSortedMap());       ...   Set s = m.keySet();  // Needn't be in synchronized block       ...   synchronized(m) {  // Synchronizing on m, not s!       Iterator i = s.iterator(); // Must be in synchronized block       while (i.hasNext())           foo(i.next());   }

SortedMap m = Collections.synchronizedSortedMap(new HashSortedMap());   SortedMap m2 = m.subMap(foo, bar);       ...   Set s2 = m2.keySet();  // Needn't be in synchronized block       ...   synchronized(m) {  // Synchronizing on m, not m2 or s2!       Iterator i = s.iterator(); // Must be in synchronized block       while (i.hasNext())           foo(i.next());   }

 

摘自：http://blog.youkuaiyun.com/qinjienj/article/details/7684340