之前的项目是控制台项目没有引入springboot相关的依赖,后续因为想更好提供接口给客户方进行调用,将控制台程序更改成springboot项目,引入springboot后,之前普通类中想调用spring ioc容器中的bean,因为普通类已经脱离了spring boot ioc范围,所有需要通过别的方式来解决。了解springboot ioc容器原理中,我们知道,在spring的整体框架中存在很多以Aware结尾的接口,Aware接口的含义是 “感知”,类似applicationcontextaware 就是感知applicationcontext,只要继承该接口就可以在该类中使用applicationcontext。
//加入component注解,让spring扫描到该bean
@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);
}
}
通过下面的测试代码进行测试,可以确保普通类获取spring ioc中的bean对象。
public static void main(String[] args){
/**
* springboot普通类获取spring容器中的bean
*
*User UserDao UserImpl,其中UserImpl中有一个获取User列表的方法getUserList
* 测试方法:
* 测试在springboot中根据UserImpl的Class对象调用getUserList方法获取用户列表数据
*/
Map param = new HashMap<String,Object>();
param.put("name","Tom");
List<User> listUser=SpringUtil.getBean(UserImpl.class).getClass()
.getDeclaredMethod("getUserList", Map.class)
.invoke(UserImpl.class,param);
}