Spring Java config包装注入的地图 [英] Spring Java config wraps injected map

问题描述

我最近从使用Spring的XML配置切换到Java配置，遇到了一个奇怪的问题。

I recently switched from using Spring's XML configuration to its Java configuration and am encountering a strange issue.

XML配置是：

<util:map id="myMap">
    <entry key="a" value="aValue"/>
    <entry key="b" value="bValue"/>
    <entry key="c" value="cValue"/>
</util:map>

<bean id="myBean" class="my.MyClass">
    <property name="myMap" ref="myMap"/>
</bean>

Java配置为：

@Bean
public Map<String, Object> myMap() {

    Map<String, Object> myMap = new HashMap<>();
    myMap.put("a", "aValue");
    myMap.put("b", "bValue");
    myMap.put("c", "cValue");

    return myMap;
}

@Bean
public MyClass myBean(@Qualifier("myMap") final Map<String, Object> myMap) {

    MyClass myBean = new MyClass();
    myBean.setMyMap(myMap);

    return myBean;
}

两个bean都在不同的文件中声明，我将它们分组在这里以使其更容易阅读。地图也包含引用，不仅包括字符串。

Both beans are declared in different files, I grouped them here to make it easier to read. The map contains references too, not only strings.

我希望能够在第二个中使用 myMap bean而是Spring注入以下地图：

I would expect to be able to use myMap in the second bean but instead Spring injects the following map:

{ myMap = { a=aValue, b=bValue, c=cValue } }

我不明白为什么Spring将地图包装到另一张地图中，为什么它不表现与XML配置相同。

I don't understand why Spring wraps the map into another map, and why it doesn't behave the same way with the XML configuration.

任何想法？

推荐答案

有一个问题 @Autowired -ing Map甚至定义了bean名称，因为根据评论你不能使用建议的 @资源注释通过使用定义bean名称的 @Value 注释，可以有另一种选择：

There is an issue @Autowired-ing a Map even defining the bean name and since as-per the comments you can't use the suggested @Resource annotation there is an alternative by using the @Value annotation defining the bean name:

@Bean
public MyClass myBean(@Value("#{myMap}") final Map<String, Object> myMap) {
//..
}

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