无xml文件的springMVC

使用springMVC我们一般都会在web.xml中配置一个dispatcher，现在我们基于用java代码的方式来使用springMVC

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.view.InternalResourceViewResolver;
import org.springframework.web.servlet.view.JstlView;

@Configuration
@EnableWebMvc
@ComponentScan
public class MVCConfig {
    @Bean
    public InternalResourceViewResolver viewResolver(){
        InternalResourceViewResolver viewResolver=new InternalResourceViewResolver();
        viewResolver.setPrefix("/WEB-INF/");
        viewResolver.setSuffix(".jsp");
        viewResolver.setViewClass(JstlView.class);
        return viewResolver;
    }
    
}

以上是一个普通的spring配置类，在其中是配置了一个jsp的ViewResolver，相信熟悉springMVC的知道这个ViewResolver。

@Configuration声明当前类为配置类，

@EnableWebMvc注解会开启一些默认配置，如ViewResolver

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRegistration.Dynamic;

import org.springframework.web.WebApplicationInitializer;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.servlet.DispatcherServlet;

public class WebConfig implements WebApplicationInitializer{

    @Override
    public void onStartup(ServletContext servletContext) throws ServletException {
        AnnotationConfigWebApplicationContext context=new AnnotationConfigWebApplicationContext();
        context.register(MVCConfig.class);
        context.setServletContext(servletContext);    
        Dynamic servlet=servletContext.addServlet("dispatcher", new DispatcherServlet(context));
        servlet.addMapping("/");
        servlet.setLoadOnStartup(1);
    }
           
}

以上代码其实就相当于我们在web.xml中配置的dispatcher，webApplicationInitializer是spring提供用来配置Servlet3.0+配置的接口，从而实现了替代web.xml的位置，实现此接口将会自动被SpringServletContainerInitialzer（用来启动Servlet3.0容器）获取到，然后我们需要注册我们前面写的MVCConfig配置类，并将其和当前servletContext关联。

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
public class HelloController {
    @RequestMapping("index")
       public String hello(){
           return "index";
       }
}

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
       Hello World
</body>
</html>

上面就是一个控制器和相应的index.jsp代码，将项目部署到tomcat中，启动，访问相应的URL。

注：以上分享来自 JavaEE开发的颠覆者: Spring Boot实战书籍

posted on 2016-05-30 16:26 minjay26 阅读(1845) 评论(1) 编辑收藏举报