Spring中ApplicationContextAware接口的说明

public class GetBeanInstance implements ApplicationContextAware {

private static final Logger logger = LoggerFactory.getLogger(GetBeanInstance.class);
private static ApplicationContext applicatiOnContext= null;
/***
* 当继承了ApplicationContextAware类之后，那么程序在调用 getBean(String)的时候会自动调用该方法，不用自己操作
*/
public void setApplicationContext(ApplicationContext applicationContext) {
logger.info("setApplicationContext :::: " + applicationContext);
GetBeanInstance.applicatiOnContext= applicationContext;
}
// 获取 bean
public static Object getBean(String beanName) {
try {
if(applicatiOnContext== null){
logger.error("applicationContext is null");
}
return applicationContext.getBean(beanName);
} catch (Exception e) {
logger.warn("not fund bean [" + beanName + "]", e);
return null;
}
}
@SuppressWarnings("unchecked")
public static T getBean(String beanName, Class clazz) {
return (T) getBean(beanName);
}
public static Object getBeanThrowException(String beanID) {
return getBeanThrowException(beanID, Object.class);
}
@SuppressWarnings("unchecked")
public static T getBeanThrowException(String beanID, Class clazz) {
if (beanID == null || "".equals(beanID)) {
throw new IllegalArgumentException("beanID is empty [" + beanID + "]");
}
try {
return (T) applicationContext.getBean(beanID);
} catch (Exception e) {
logger.error("not fund bean [" + beanID + "]", e);
throw new NullPointerException("not fund bean [" + beanID + "] !!!!!!!");
}
}
}