java - ApplicationContextAware 在 Spring 3.0 中不起作用

Question

我正在尝试一个简单的示例，但没有成功。

ApplicationContextHolder 类实现 Aware:

@Component
public class ApplicationContextHolder implements ApplicationContextAware {

private static ApplicationContext context;

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

public static ApplicationContext getApplicationContext(){
    return context;
}
}

App.java

public static void main( String[] args )
{
    ApplicationContext context = ApplicationContextHolder.getApplicationContext();
    // context in above line is coming as null
}

下面是我的 xml 条目:

<context:component-scan base-package="com.XXX" />

请告诉我为什么 context 在 App.jaa 类中为 null。我是否需要为在 xml 文件中某处实现 Aware 的类创建一些条目？

Answer 1

你必须先初始化ApplicationContext

public static void main( String[] args )
{
  ApplicationContext context = new ClassPathXmlApplicationContext("spring.xml");
  // 'spring.xml' has to add ApplicationContextHolder to its scan path

  ApplicationContext contextFromHolder =
    ApplicationContextHolder.getApplicationContext();
}