＆QUOT;不能创建通用阵列..＆QUOT; - 如何创建地图＆LT的数组;字符串对象＆gt ;? [英] "Cannot create generic array of .." - how to create an Array of Map<String, Object>?

问题描述

我想用SimpleJdbcInsert类类executeBatch方法

I would like to use simpleJdbcInsert class and executeBatch method

public int[] executeBatch(Map<String,Object>[] batch)

<一个href=\"http://static.springsource.org/spring/docs/2.5.x/api/org/springframework/jdbc/core/simple/SimpleJdbcInsert.html\">http://static.springsource.org/spring/docs/2.5.x/api/org/springframework/jdbc/core/simple/SimpleJdbcInsert.html

所以，我需要通过的数组地图＆LT;弦乐，对象＆gt; 作为参数。如何创建这样的阵列？
我试过是

So I need to pass an array of Map<String,Object> as parameter. How to create such an array? What I tried is

Map<String, Object>[] myArray = new HashMap<String, Object>[10]

有错误：无法创建地图＆LT通用阵列;弦乐，对象＆gt;

A 列表与LT;地图＆LT;弦乐，对象＆gt;＆GT; 会更容易些，但我想我需要一个数组。那么如何创建的数组地图＆LT;弦乐，对象＆gt; ？
谢谢

A List<Map<String, Object>> would be easier, but I guess I need an array. So how to create an array of Map<String, Object> ? Thanks

推荐答案

[] ）。相反，你创建原始类型的数组（地图[] ），并将其转换为地图＆LT;弦乐，对象＆gt; [] 。这将导致不可避免的（但SUP pressible）编译器警告。

Because of how generics in Java work, you cannot directly create an array of a generic type (such as Map<String, Object>[]). Instead, you create an array of the raw type (Map[]) and cast it to Map<String, Object>[]. This will cause an unavoidable (but suppressible) compiler warning.

这应该为你所需要的工作：

This should work for what you need:

Map<String, Object>[] myArray = (Map<String, Object>[]) new Map[10];

您可能希望从正在显示注释这与发生在@苏pressWarnings方法（未登记），以prevent警告。

You may want to annotate the method this occurs in with @SupressWarnings("unchecked"), to prevent the warning from being shown.

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