Question

java Map数组定义出现的警告

public static Map<String, String> [] maps = null ;
public static void newDBParameter(int length){
maps = new HashMap[length] ;//黄色警告
}

maps = new HashMap[length] 这句该怎么写才消除警告
new HashMap<String,String>[length];//报错

Answer 1

应该是maps = new HashMap(length)吧，数组采用[]定义。
看看hashmap构造函数：

Constructor and Description

HashMap()
Constructs an empty HashMap with the default initial
capacity (16) and the default load factor (0.75).

HashMap(int initialCapacity)
Constructs an empty HashMap with the specified initial
capacity and the default load factor (0.75).

HashMap(int initialCapacity,
float loadFactor)
Constructs an empty HashMap with the specified initial
capacity and load factor.

HashMap(Map<?
extends K,? extends V> m)
Constructs a new HashMap with the same mappings as the
specified Map.