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最新推荐文章于 2024-09-30 13:00:00 发布

原创最新推荐文章于 2024-09-30 13:00:00 发布 · 432 阅读

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每次comparator都不记得写object的leixing

Arrays.sort ( intervals, new Comparator<Interval> (){
public int compare ( Interval in1, Interval in2 ){
return in1.start - in2.start;
}
});

HashMap

`void`	`clear()` Removes all of the mappings from this map.
`Object`	`clone()` Returns a shallow copy of this `HashMap` instance: the keys and values themselves are not cloned.
`boolean`	`containsKey(Object key)` Returns `true` if this map contains a mapping for the specified key.
`boolean`	`containsValue(Object value)` Returns `true` if this map maps one or more keys to the specified value.
`Set<Map.Entry<K,V>>`	`entrySet()` Returns a `Set` view of the mappings contained in this map.
`V`	`get(Object key)` Returns the value to which the specified key is mapped, or `null` if this map contains no mapping for the key.
`boolean`	`isEmpty()` Returns `true` if this map contains no key-value mappings.
`Set<K>`	`keySet()` Returns a `Set` view of the keys contained in this map.
`V`	`put(K key, V value)` Associates the specified value with the specified key in this map.
`void`	`putAll(Map<? extends K,? extends V> m)` Copies all of the mappings from the specified map to this map.
`V`	`remove(Object key)` Removes the mapping for the specified key from this map if present.
`int`	`size()` Returns the number of key-value mappings in this map.
`Collection<V>`	`values()` Returns a `Collection` view of the values contained in this map.