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SparseArray ArrayMap

2017-01-06 14:22:39| 分类： android | 标签： |举报 |字号大中小订阅

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对比HashMap，性能空间上占用更少

应用场景：

1、数据量都在千级以内
2、如果key的类型已经确定为int类型，那么使用SparseArray，因为它避免了自动装箱的过程，如果key为long类型，它还提供了一个LongSparseArray来确保key为long类型时的使用

3、如果key类型为其它的类型，则使用ArrayMap

ArrayMap<Key, Value> arrayMap = new ArrayMap<>();

SparseArray<Object> array = new SparseArray<>();

添加数据

public V put(K key, V value)

获取数据

public V get(Object key)

删除数据

public V remove(Object key)

特有方法

它和SparseArray一样同样也有两个更方便的获取数据方法：

public K keyAt(int index)
public V valueAt(int index)

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