android软摘引之SoftReferenceHashTable

public class SoftReferenceHashTable<K,V> {    Hashtable<K, SoftReference<V>> mTable = new Hashtable<K, SoftReference<V>>();        public V put(K key, V value) {        SoftReference<V> old = mTable.put(key, new SoftReference<V>(value));        if (old == null)            return null;        return old.get();    }        public V get(K key) {        SoftReference<V> val = mTable.get(key);        if (val == null)            return null;        V ret = val.get();        if (ret == null)            mTable.remove(key);        return ret;    }        public V remove(K k) {        SoftReference<V> v = mTable.remove(k);        if (v == null)            return null;        return v.get();    }}

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