Spring 获取当前的 ApplicationContext

只要注射。

@Autowired
private ApplicationContext appContext;

or implement this interface: ApplicationContextAware

将此添加到代码中

@Autowired
private ApplicationContext _applicationContext;


//Add below line in your calling method
MyClass class = (MyClass) _applicationContext.getBean("myClass");


// Or you can simply use this, put the below code in your controller data member declaration part.
@Autowired
private MyClass myClass;

这将简单地将 myClass 注入到您的应用程序中

步骤1 : 在类中注入以下代码

@Autowired
private ApplicationContext _applicationContext;

步骤2 : 写 Getter & Setter

步骤3 : 在定义 bean 的 xml 文件中定义 autowire = “ byType”

我认为这个 链接演示了在任何地方获取应用程序上下文的最佳方法，即使是在非 bean 类中。我觉得很有用。希望你也一样。下面是它的抽象代码

Create a new class ApplicationContextProvider.java

package com.java2novice.spring;


import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;


public class ApplicationContextProvider implements ApplicationContextAware{


private static ApplicationContext context;


public static ApplicationContext getApplicationContext() {
return context;
}


@Override
public void setApplicationContext(ApplicationContext ac)
throws BeansException {
context = ac;
}
}

在 application-context. xml 中添加一个条目

<bean id="applicationContextProvider"
class="com.java2novice.spring.ApplicationContextProvider"/>

在注释中(而不是 application-context.xml)

@Component
public class ApplicationContextProvider implements ApplicationContextAware{
...
}

像这样理解上下文

TestBean tb = ApplicationContextProvider.getApplicationContext().getBean("testBean", TestBean.class);

干杯！

如果您需要从 HttpServlet 本身不是由 Spring 实例化的中访问上下文(因此@Autowire 和 ApplicationContextAware 都不能工作) ..。

WebApplicationContext applicationContext = WebApplicationContextUtils.getWebApplicationContext(getServletContext());

或者

SpringBeanAutowiringSupport.processInjectionBasedOnCurrentContext(this);

As for some of the other replies, 做这件事之前三思而后行:

new ClassPathXmlApplicationContext("..."); // are you sure?

... 因为这并不能给你当前的上下文，而是为你创建了另一个实例。这意味着1)有意义的内存块和2) bean 不在这两个应用程序上下文之间共享。

另一种方法是通过 servlet 注入 applicationContext。

这是在使用 SpringWeb 服务时如何注入依赖关系的一个示例。

<servlet>
<servlet-name>my-soap-ws</servlet-name>
<servlet-class>org.springframework.ws.transport.http.MessageDispatcherServlet</servlet-class>
<init-param>
<param-name>transformWsdlLocations</param-name>
<param-value>false</param-value>
</init-param>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:my-applicationContext.xml</param-value>
</init-param>
<load-on-startup>5</load-on-startup>


</servlet>

另一种方法是在 web.xml 中添加应用程序 Context，如下所示

<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>
/WEB-INF/classes/my-another-applicationContext.xml
classpath:my-second-context.xml
</param-value>
</context-param>

基本上，您试图告诉 servlet 它应该查找在这些上下文文件中定义的 bean。

基于 Vivek 的回答，但我认为下面这些会更好:

@Component("applicationContextProvider")
public class ApplicationContextProvider implements ApplicationContextAware {


private static class AplicationContextHolder{


private static final InnerContextResource CONTEXT_PROV = new InnerContextResource();


private AplicationContextHolder() {
super();
}
}


private static final class InnerContextResource {


private ApplicationContext context;


private InnerContextResource(){
super();
}


private void setContext(ApplicationContext context){
this.context = context;
}
}


public static ApplicationContext getApplicationContext() {
return AplicationContextHolder.CONTEXT_PROV.context;
}


@Override
public void setApplicationContext(ApplicationContext ac) {
AplicationContextHolder.CONTEXT_PROV.setContext(ac);
}
}

从实例方法写入静态字段是一种不好的做法，如果操纵多个实例，这种做法是危险的。

如果您正在实现一个不是由 Spring 实例化的类，比如 JsonSerializer，那么您可以使用:

WebApplicationContext context = ContextLoader.getCurrentWebApplicationContext();
MyClass myBean = context.getBean(MyClass.class);

在 Spring 应用程序中获得应用程序上下文的方法有很多，如下所示:

1. 通过 ApplicationContextAware :

   import org.springframework.beans.BeansException;
   import org.springframework.context.ApplicationContext;
   import org.springframework.context.ApplicationContextAware;
   
   
   public class AppContextProvider implements ApplicationContextAware {
   
   
   private ApplicationContext applicationContext;
   
   
   @Override
   public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
   this.applicationContext = applicationContext;
   }
   }
   

Here setApplicationContext(ApplicationContext applicationContext) method you will get the applicationContext

2. Via Autowired:

   @Autowired
   private ApplicationContext applicationContext;
   

Here @Autowired keyword will provide the applicationContext.

For more info visit this thread

Thanks :)

Even after adding @Autowire if your class is not a RestController or Configuration Class, the applicationContext object was coming as null. Tried Creating new class with below and it is working fine:

@Component
public class SpringContext implements ApplicationContextAware{


private static ApplicationContext applicationContext;


@Override
public void setApplicationContext(ApplicationContext applicationContext) throws
BeansException {
this.applicationContext=applicationContext;
}
}

然后您可以根据需要在同一个类中实现一个 getter 方法，比如通过以下方法获取实现的类引用:

    applicationContext.getBean(String serviceName,Interface.Class)

比使用@Autowired 更好的方法是让它通过构造函数注入。找到一些参数 pro 构造函数注入 给你

@Component
public class MyClass{
private final ApplicationContext applicationContext;


public MyClass(ApplicationContext applicationContext){
this.applicationContext = applicationContext;
}


//here will be your methods using the applicationcontext
}