spring - 如何将XML配置转换为Java配置？

我想将此XML配置转换为Java，但是有些人在寻找正确的方法上遇到了麻烦。

<bean class="org.springframework.beans.factory.config.MethodInvokingFactoryBean">
    <property name="targetObject">
      <bean class="org.springframework.beans.factory.config.MethodInvokingFactoryBean">
        <property name="targetClass" value="java.lang.System"/>
        <property name="targetMethod" value="getProperties"/>
      </bean>
    </property>
    <property name="targetMethod" value="putAll"/>
    <property name="arguments">
      <util:properties>
        <prop key="key1">value1</prop>
        <prop key="key2">value2</prop>
        <prop key="key3">value3</prop>
        <prop key="key4">value4</prop>
        <prop key="key5">value5</prop>
      </util:properties>
    </property>
</bean>

它几乎可以正常工作，但是我收到关于putAll方法的错误。应该在Properties对象上调用它，但是使用我的Java配置（见下文），它将尝试在MethodInvokingFactoryBean对象上调用它。

@Bean
public MethodInvokingFactoryBean getMethodInvokingFactoryBean() throws IOException {
    final MethodInvokingFactoryBean methodInvokingFactoryBean = new MethodInvokingFactoryBean();
    final MethodInvokingFactoryBean target = new MethodInvokingFactoryBean();
    target.setTargetClass(System.class);
    target.setTargetMethod("getProperties");
    methodInvokingFactoryBean.setTargetObject(target);
    methodInvokingFactoryBean.setTargetMethod("putAll");
    final Properties properties = new Properties();
    properties.put("key1", "value1");
    properties.put("key2", "value2");
    properties.put("key3", "value3");
    properties.put("key4", "value4");
    properties.put("key5", "value5");
    final PropertiesFactoryBean propertiesFactoryBean = new PropertiesFactoryBean();
    propertiesFactoryBean.setProperties(properties);
    methodInvokingFactoryBean.setArguments(propertiesFactoryBean);
    return methodInvokingFactoryBean;
  }

所以我现在得到的错误是：
java.lang.NoSuchMethodException: org.springframework.beans.factory.config.MethodInvokingFactoryBean.putAll(org.springframework.beans.factory.config.PropertiesFactoryBean)因为应该在putAll对象上调用Properties ..我在这里做什么错的？

最佳答案

之所以得到NoSuchMethodException是因为putAll中没有MethodInvokingFactoryBean方法。 putAll方法来自Properties::putAll，而Hashtable::putAll是从this继承的。请参阅帖子。这是与您发布的xml类似的Java配置：

@Bean
public MethodInvokingFactoryBean getMethodInvokingFactoryBean() {
    final MethodInvokingFactoryBean methodInvokingFactoryBean =
            new MethodInvokingFactoryBean();

    Map<String, String> map = new HashMap<>();
    map.put("key1", "value1");
    // add more key-value pairs

    methodInvokingFactoryBean.setTargetObject(new Properties());
    methodInvokingFactoryBean.setTargetMethod("putAll");
    methodInvokingFactoryBean.setArguments(map);

    return methodInvokingFactoryBean;
}