1. 概述
本文介绍spring boot里的spring mvc部分的用法,主要包括如下:
- 1 实现 spring boot 集成jsp: @Controller+ @RequestMapping
- 2 模拟登录功能: ModelAndView
- 3 spring boot 实现restful接口:@RestController
2. 第一个demo: spring boot集成jsp
工程: mvc
本节实现spring boot集成jsp功能
2.1. pom.xml
引入相关的类
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<artifactId>mvc</artifactId>
<packaging>jar</packaging>
<name>mvc</name>
<description>Demo project for spring mvc</description>
<parent>
<groupId>com.hry.spring</groupId>
<artifactId>parent</artifactId>
<version>0.0.1-SNAPSHOT</version>
<relativePath>../parent/pom.xml</relativePath>
</parent>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
<dependencies>
<!-- spring mvc -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
<version>2.3</version>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.12</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-tomcat</artifactId>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.apache.tomcat.embed</groupId>
<artifactId>tomcat-embed-jasper</artifactId>
<!--<scope>provided</scope>-->
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-tomcat</artifactId>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>jstl</artifactId>
</dependency>
</dependencies>
</project>
2.2. application.properties
# 页面默认前缀目录
spring.mvc.view.prefix=/WEB-INF/page/
## 响应页面默认后缀
spring.mvc.view.suffix=.jsp
注意:自己写的jsp页面请放置到这个目录下“META-INF/resources/WEB-INF/page/”
2.3. JSP页面配置
META-INF/resources/:请将jsp文件配置在这个目录下,如果不配置在这个目录下,则会出现无法找到jsp页面的问题
META-INF/resources/WEB-INF/page/first/index.jsp
<!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>
This is spring mvc first page.
</body>
</html>
2.4. FirstControl
第一个测试control
@Controller: 定义controller层类 @RequestMapping:定义本请求的请求url
请求后,返回”META-INF/resources/WEB-INF/page/first/index.jsp”的内容
@Controller
public class FirstControl {
/**
* http://127.0.0.1:8080/first
* 返回页面META-INF/resources/WEB-INF/page/first/index.jsp
* @param model
* @return
*/
@RequestMapping("/first")
public String first(Model model) {
model.addAttribute("message", "Hello World!");
return "first/index";
}
}
2.5. 启动类MvcApplication
MvcApplication 需要继承SpringBootServletInitializer,重写configure方法。方法fastJsonHttpMessageConverters表示使用fastjson做为json解析的工具
spring mvc的demo都使用这个做为启动类
@SpringBootApplication
public class MvcApplication extends SpringBootServletInitializer {
@Override
protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
return application.sources(MvcApplication.class);
}
public static void main(String[] args) {
SpringApplication.run(MvcApplication.class, args);
}
/**
* 使用fastjson做为spring mvc的json序列化
* @return
*/
@Bean
public HttpMessageConverters fastJsonHttpMessageConverters() {
FastJsonHttpMessageConverter fastConverter = new FastJsonHttpMessageConverter();
FastJsonConfig fastJsonConfig = new FastJsonConfig();
fastJsonConfig.setSerializerFeatures(SerializerFeature.PrettyFormat);
fastConverter.setFastJsonConfig(fastJsonConfig);
HttpMessageConverter<?> converter = fastConverter;
return new HttpMessageConverters(converter);
}
}
2.6. 测试
执行请求: http://127.0.0.1:8080/first
返回内容:
This is spring mvc first page.
3. 第二个demo: 实现简单的登陆的功能
和上节在相同的工程mvc中,本节只列出不同的地方。 功能如下 :我们先登录from.jsp后,用户输入到信息,如果成功,则转到succ.jsp,否则转到home.jsp
3.1. 相关jsp页面
以下页面配置在这个目录中:META-INF/resources/WEB-INF/page/login
form.jsp
登录界面
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<form action="login" method="post">
username:<input type="text" name="username" />
<p>
password:<input type="password" name="password" />
<p>
<input type="submit" value="submit" />
</form>
</body>
</html>
home.jsp
<!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>
<h2>home</h2>
</body>
</html>
succ.jsp
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<h2>登陆</h2>
username:${username }
<p>password:${password }
</body>
</html>
3.2. LoginController
登录的controller类
String login(): 此方法会转到上节的form.jsp页面 ModelAndView login(String username,String password):演示ModelAndView 的用法,如果成功,则转到succ.jsp,否则转到home.jsp
@Controller
public class LoginController {
/**
* 登录页面:http://127.0.0.1:8080//login/login
*
* @return
*/
@RequestMapping(value="/login/form",method=RequestMethod.GET)
public String login(){
return "/login/form";
}
/***
* 用户登陆
* <p>注解配置,只允许POST提交到该方法
* @param username
* @param password
* @return
*/
@RequestMapping(value="/login/login",method=RequestMethod.POST)
public ModelAndView login(String username,String password){
//验证传递过来的参数是否正确,否则返回到登陆页面。
if(this.checkParams(new String[]{username,password})){
//指定要返回的页面为succ.jsp
ModelAndView mav = new ModelAndView("/login/succ");
//将参数返回给页面
mav.addObject("username",username);
mav.addObject("password", password);
return mav;
}
return new ModelAndView("/login/home");
}
/***
* 验证参数是否为空
* @param params
* @return
*/
private boolean checkParams(String[] params){
for(String param:params){
if(param==""||param==null||param.isEmpty()){
return false;
}
}
return true;
}
}
3.3. 测试
登录成功功能
执行url : http://localhost:8080/login/form
随便填入信息,则返回:
登陆
username:lastName
password:2222
登录失败功能
执行url : http://localhost:8080/login/form
不填写内容,则返回:
home
4. 第三个demo: spring boot 实现restful接口
和上节在相同的工程mvc中,本节只列出不同的地方。
4.1. VO
class VO {
private String name;
private String value;
// set/get略
}
4.2. @RestController
@RestController: 定义此类是
@RequestMapping:定义在类上,则所有方法的url前缀是rest;定义在方法上,则作用在方法上
VO getUser():此方法演示返回一个对象,@RestController会自动转化为json字符串
String getUserHtml:此方法演示直接返回一个字段串
@RestController
@RequestMapping(value = "/rest")
public class RestControllerTest {
/**
* 方法返回对象
* http://127.0.0.1:8080/rest/vo
* @return
*/
@RequestMapping(value = "/vo", method = RequestMethod.GET)
public VO getUser() {
VO vo = new VO();
vo.setName("name");
vo.setValue("value");
return vo;
}
/**
*
* 直接返回内容
* http://localhost:8080/rest/string
* @return
*/
@RequestMapping(value = "/string", method = RequestMethod.GET)
// @ResponseStatus(HttpStatus.OK)
public String getUserHtml() {
return "{'example':'---'}";
}
}
4.3. 测试
测试演示返回一个对象,@RestController会自动转化为json字符串
执行url : http://localhost:8080/rest/vo
返回:
{ "name":"name", "value":"value" }
测试直接返回一个字符串:
执行url : http://localhost:8080/rest/string
返回:
"{'example':'---'}"
6. 代码
上文的详细代码见github代码,请尽量使用tag v0.3,不要使用master,因为master一直在变,不能保证文章中代码和github上的代码一直相同