弹簧依赖注射自动装配空 [英] Spring Dependency Injection Autowiring Null

问题描述

我可以使用RestTemplate并自动连线。然而，我想将我的休息模板相关的部分代码移动到另一个类中，如下所示：

I was able to use RestTemplate and autowire it. However I want to move my rest template related part of code into another class as follows:

public class Bridge {

    private final String BASE_URL = "http://localhost:8080/u";

    @Autowired
    RestTemplate restTemplate;

    public void addW() {
       Map<String, String> x = new HashMap<String, String>();
       W c = restTemplate.getForObject(BASE_URL + "/device/yeni", W.class, x);
       System.out.println("Here!");
    }
}

而在另一个类中，我称之为：

And at another class I call it:

...
Bridge wb = new Bridge();
wb.addW();
...

我是Spring和Dependency Injection术语的新手。我的 restTemplate 变量为null并抛出异常。我可以做什么如何解决它（我不知道它是否与我使用新的关键字相关）？

I am new to Spring and Dependency Injection terms. My restTemplate variable is null and throws an exception. What can I do it how to solve it(I don't know is it related to I use new keyword)?

推荐答案

使用 Bridge wb = new Bridge（）不适用于依赖注入。由于 wB 未被Spring管理，所以 restTemplate 不会被注入。

Using Bridge wb = new Bridge() does not work with dependency injection. Your restTemplate is not injected, because wb in not managed by Spring.

您必须使您的 Bridge 一个Spring bean本身，例如通过注释：

You have to make your Bridge a Spring bean itself, e.g. by annotation:

@Service
public class Bridge {
    // ...
}

或通过bean声明：

<bean id="bridge" class="Bridge"/>

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