spring 几种获得bean的方法
spring 几种获得bean的方法几种获得当对serviceLocator实例时就自动设置BeanFactory,以便后来可直接用beanFactory
public class ServiceLocator implements BeanFactoryAware {
??? private static BeanFactory beanFactory = null;
?
??? private static ServiceLocator servlocator = null;
?
??? public void setBeanFactory(BeanFactory factory) throws BeansException {
??????? this.beanFactory = factory;
??? }
?
??? public BeanFactory getBeanFactory() {
??????? return beanFactory;
??? }
?
??
??? public static ServiceLocator getInstance() {
??????? if (servlocator == null)
????????????? servlocator = (ServiceLocator) beanFactory.getBean("serviceLocator");
??????? return servlocator;
??? }
?
??? /**
??? * 根据提供的bean名称得到相应的服务类????
??? * @param servName bean名称????
??? */
??? public static Object getService(String servName) {
??????? return beanFactory.getBean(servName);
??? }
?
??? /**
??? * 根据提供的bean名称得到对应于指定类型的服务类
??? * @param servName bean名称
??? * @param clazz 返回的bean类型,若类型不匹配,将抛出异常
??? */
??? public static Object getService(String servName, Class clazz) {
??????? return beanFactory.getBean(servName, clazz);
??? }
}
action调用:
?
public class UserAction extends BaseAction implements Action,ModelDriven{
???
??? private Users user = new Users();
??? protected ServiceLocator service = ServiceLocator.getInstance();
??? UserService userService = (UserService)service.getService("userService");
?
??? public String execute() throws Exception {????????
??????? return SUCCESS;
??? }
?
? public Object getModel() {
??????? return user;
??? }????
???
??? public String getAllUser(){
??????? HttpServletRequest request = ServletActionContext.getRequest();????????
??????? List ls=userService.LoadAllObject( Users.class );
??????? request.setAttribute("user",ls);????
??????? this.setUrl("/yonghu.jsp");
??????? return SUCCESS;
??? }
}
三：方法三实现ApplicationContextAware
一定要在当对SpringContextUtil 实例时就自动设置applicationContext,以便后来可直接用applicationContext
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public class SpringContextUtil implements ApplicationContextAware {
? private static ApplicationContext applicationContext;???? //Spring应用上下文环境
?
? /**
? * 实现ApplicationContextAware接口的回调方法，设置上下文环境??
? * @param applicationContext
? * @throws BeansException
? */
? public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
??? SpringContextUtil.applicationContext = applicationContext;
? }
?
? /**
? * @return ApplicationContext
? */
? public static ApplicationContext getApplicationContext() {
??? return applicationContext;
? }
?
? /**
? * 获取对象??
? * @param name
? * @return Object 一个以所给名字注册的bean的实例
? * @throws BeansException
? */
? public static Object getBean(String name) throws BeansException {
??? return applicationContext.getBean(name);
? }
?
? /**
? * 获取类型为requiredType的对象
? * 如果bean不能被类型转换，相应的异常将会被抛出（BeanNotOfRequiredTypeException）
? * @param name?????? bean注册名
? * @param requiredType 返回对象类型
? * @return Object 返回requiredType类型对象
? * @throws BeansException
? */
? public static Object getBean(String name, Class requiredType) throws BeansException {
??? return applicationContext.getBean(name, requiredType);
? }
?
? /**
? * 如果BeanFactory包含一个与所给名称匹配的bean定义，则返回true
? * @param name
? * @return boolean
? */
? public static boolean containsBean(String name) {
??? return applicationContext.containsBean(name);
? }
?
? /**
? * 判断以给定名字注册的bean定义是一个singleton还是一个prototype。
? * 如果与给定名字相应的bean定义没有被找到，将会抛出一个异常（NoSuchBeanDefinitionException）??
? * @param name
? * @return boolean
? * @throws NoSuchBeanDefinitionException
? */
? public static boolean isSingleton(String name) throws NoSuchBeanDefinitionException {
??? return applicationContext.isSingleton(name);
? }
?
? /**
? * @param name
? * @return Class 注册对象的类型
? * @throws NoSuchBeanDefinitionException
? */
? public static Class getType(String name) throws NoSuchBeanDefinitionException {
??? return applicationContext.getType(name);
? }
?
? /**
? * 如果给定的bean名字在bean定义中有别名，则返回这些别名??
? * @param name
? * @return
? * @throws NoSuchBeanDefinitionException
? */
? public static String[] getAliases(String name) throws NoSuchBeanDefinitionException {
??? return applicationContext.getAliases(name);
? }
}
?
action调用：
package com.anymusic.oa.webwork;
?
import java.util.List;
import java.util.Map;
?
import javax.servlet.http.HttpServletRequest;
?
import com.anymusic.oa.commons.service.ServiceLocator;
import com.anymusic.oa.hibernate.pojo.Role;
import com.anymusic.oa.hibernate.pojo.Users;
import com.anymusic.oa.spring.IUserService;
import com.opensymphony.webwork.ServletActionContext;
import com.opensymphony.xwork.Action;
import com.opensymphony.xwork.ActionContext;
import com.opensymphony.xwork.ModelDriven;
?
public class UserAction extends BaseAction implements Action,ModelDriven{
???
??? private Users user = new Users();
?//不用再加载springContext.xml文件,因为在web.xml中配置了,在程序中启动是就有了.???
??? UserService userService = (UserService) SpringContextUtil.getBean("userService");
???
??? public String execute() throws Exception {????????
??????? return SUCCESS;
??? }
?
? public Object getModel() {
??????? return user;
??? }????
???
??? public String getAllUser(){
??????? HttpServletRequest request = ServletActionContext.getRequest();????????
??????? List ls=userService.LoadAllObject( Users.class );
??????? request.setAttribute("user",ls);????
??????? this.setUrl("/yonghu.jsp");
??????? return SUCCESS;
??? }
}
?
四.通过servlet 或listener设置spring的ApplicationContext,以便后来引用.
注意分别extends? ContextLoaderListener和ContextLoaderServlet .然后就可用SpringContext来getBean.
覆盖原来在web.xml中配置的listener或servlet.
public class SpringContext? {
? private static ApplicationContext applicationContext;???? //Spring应用上下文环境
? */
? public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
??? SpringContextUtil.applicationContext = applicationContext;
? }
?
? /**
? * @return ApplicationContext
? */
? public static ApplicationContext getApplicationContext() {
??? return applicationContext;
? }
? */
? public static Object getBean(String name) throws BeansException {
??? return applicationContext.getBean(name);
? }
}
public class SpringContextLoaderListener extends ContextLoaderListener{? //
?public void contextInitialized(ServletContextEvent event) {??
??super.contextInitialized(event);
??SpringContext.setApplicationContext(
????WebApplicationContextUtils.getWebApplicationContext(event.getServletContext())
????);
?}
}
public class SpringContextLoaderServlet extends ContextLoaderServlet {
?private ContextLoader contextLoader;
??? public void init() throws ServletException {
??????? this.contextLoader = createContextLoader();
??????? SpringContext.setApplicationContext(this.contextLoader.initWebApplicationContext(getServletContext()));
??? }
}
