SynchronizedMap

前言

线程安全的map类，底层对传递的map进行加锁处理。

初始化

数据全部存储在m中，进行了一层包装处理。

private final Map<K,V> m;     // Backing Map
final Object      mutex;        // Object on which to synchronize
SynchronizedMap(Map<K,V> m) {
    this.m = Objects.requireNonNull(m);
    mutex = this;
}
SynchronizedMap(Map<K,V> m, Object mutex) {
    this.m = m;
    this.mutex = mutex;
}

主要方法

主要方法都是对mutex进行加锁处理，以便安全访问。

public int size() {
    synchronized (mutex) {return m.size();}
}
public boolean isEmpty() {
    synchronized (mutex) {return m.isEmpty();}
}
public boolean containsKey(Object key) {
    synchronized (mutex) {return m.containsKey(key);}
}
public boolean containsValue(Object value) {
    synchronized (mutex) {return m.containsValue(value);}
}
public V get(Object key) {
    synchronized (mutex) {return m.get(key);}
}
public V put(K key, V value) {
    synchronized (mutex) {return m.put(key, value);}
}
public V remove(Object key) {
    synchronized (mutex) {return m.remove(key);}
}
public void putAll(Map<? extends K, ? extends V> map) {
    synchronized (mutex) {m.putAll(map);}
}
public void clear() {
    synchronized (mutex) {m.clear();}
}