无法注入原因：
有的时候我们有一些类并不想注入Spring容器中，有Spring容器实例化，但是我们又想使用Spring容器中的一些对象，所以就只能借助工具类来获取了
工具类：
package com.mikey.design.utils; import org.springframework.beans.BeansException;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;
/**
* @author Mikey
* @Title:
* @Description:
* @Email:[email protected]
* @date 2018/12/3 21:57
* @Version 1.0
*/
@Component
public class SpringUtil implements ApplicationContextAware {
private static ApplicationContext applicationContext = null; public SpringUtil() {
} public void setApplicationContext(ApplicationContext arg0) throws BeansException {
if (applicationContext == null) {
applicationContext = arg0;
} } public static ApplicationContext getApplicationContext() {
return applicationContext;
} public static void setAppCtx(ApplicationContext webAppCtx) {
if (webAppCtx != null) {
applicationContext = webAppCtx;
}
} /**
* 拿到ApplicationContext对象实例后就可以手动获取Bean的注入实例对象
*/
public static <T> T getBean(Class<T> clazz) {
return getApplicationContext().getBean(clazz);
} public static <T> T getBean(String name, Class<T> clazz) throws ClassNotFoundException {
return getApplicationContext().getBean(name, clazz);
} public static final Object getBean(String beanName) {
return getApplicationContext().getBean(beanName);
} public static final Object getBean(String beanName, String className) throws ClassNotFoundException {
Class clz = Class.forName(className);
return getApplicationContext().getBean(beanName, clz.getClass());
} public static boolean containsBean(String name) {
return getApplicationContext().containsBean(name);
} public static boolean isSingleton(String name) throws NoSuchBeanDefinitionException {
return getApplicationContext().isSingleton(name);
} public static Class<?> getType(String name) throws NoSuchBeanDefinitionException {
return getApplicationContext().getType(name);
} public static String[] getAliases(String name) throws NoSuchBeanDefinitionException {
return getApplicationContext().getAliases(name);
}
}
使用：