问题描述
我想使用 simpleJdbcInsert 类和 executeBatch 方法
I would like to use simpleJdbcInsert class and executeBatch method
public int[] executeBatch(Map<String,Object>[] batch)
http://static.springsource.org/spring/docs/2.5.x/api/org/springframework/jdbc/core/simple/SimpleJdbcInsert.html
所以我需要传递一个 Map 数组作为参数.如何创建这样的数组?我尝试的是
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]
错误:无法创建 Map
A List<Map<String, Object>> 会更容易，但我想我需要一个数组.那么如何创建 Map<String, Object> 的数组呢?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
由于Java中泛型的工作方式，不能直接创建泛型类型的数组(如MapMap[]) 的数组并将其转换为 Map.这将导致不可避免(但可抑制)的编译器警告.
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.
这应该可以满足您的需要:
This should work for what you need:
Map<String, Object>[] myArray = (Map<String, Object>[]) new Map[10];
您可能希望使用 @SuppressWarnings("unchecked") 注释发生这种情况的方法，以防止显示警告.
You may want to annotate the method this occurs in with @SuppressWarnings("unchecked"), to prevent the warning from being shown.
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