SpringMVC详细示例实战教程

一、SpringMVC基础入门,创建一个HelloWorld程序

  1.首先,导入SpringMVC需要的jar包。

  2.添加Web.xml配置文件中关于SpringMVC的配置


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<!--configure the setting of springmvcDispatcherServlet and configure the mapping-->

<servlet>

    <servlet-name>springmvc</servlet-name>

    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>

    <init-param>

          <param-name>contextConfigLocation</param-name>

          <param-value>classpath:springmvc-servlet.xml</param-value>

      </init-param>

      <!-- <load-on-startup>1</load-on-startup> -->

</servlet>

<servlet-mapping>

    <servlet-name>springmvc</servlet-name>

    <url-pattern>/</url-pattern>

</servlet-mapping>

  3.在src下添加springmvc-servlet.xml配置文件


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<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"

    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

    xmlns:context="http://www.springframework.org/schema/context"

    xmlns:mvc="http://www.springframework.org/schema/mvc"

    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd

        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.1.xsd

        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.1.xsd">                   

    <!-- scan the package and the sub package -->

    <context:component-scan base-package="test.SpringMVC"/>

    <!-- don‘t handle the static resource -->

    <mvc:default-servlet-handler />

    <!-- if you use annotation you must configure following setting -->

    <mvc:annotation-driven />

    

    <!-- configure the InternalResourceViewResolver -->

    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"

            id="internalResourceViewResolver">

        <!-- 前缀 -->

        <property name="prefix" value="/WEB-INF/jsp/" />

        <!-- 后缀 -->

        <property name="suffix" value=".jsp" />

    </bean>

</beans>

  4.在WEB-INF文件夹下创建名为jsp的文件夹,用来存放jsp视图。创建一个hello.jsp,在body中添加“Hello World”。

  5.建立包及Controller,如下所示

  6.编写Controller代码


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@Controller

@RequestMapping("/mvc")

public class mvcController {

    @RequestMapping("/hello")

    public String hello(){       

        return "hello";

    }

}

  7.启动服务器,键入 http://localhost:8080/项目名/mvc/hello

 二、配置解析

  1.Dispatcherservlet

  DispatcherServlet是前置控制器,配置在web.xml文件中的。拦截匹配的请求,Servlet拦截匹配规则要自已定义,把拦截下来的请求,依据相应的规则分发到目标Controller来处理,是配置spring MVC的第一步。

  2.InternalResourceViewResolver

  视图名称解析器

  3.以上出现的注解

  @Controller 负责注册一个bean 到spring 上下文中

  @RequestMapping 注解为控制器指定可以处理哪些 URL 请求

 三、SpringMVC常用注解

  @Controller

  负责注册一个bean 到spring 上下文中

  @RequestMapping

  注解为控制器指定可以处理哪些 URL 请求

  @RequestBody

  该注解用于读取Request请求的body部分数据,使用系统默认配置的HttpMessageConverter进行解析,然后把相应的数据绑定到要返回的对象上 ,再把HttpMessageConverter返回的对象数据绑定到 controller中方法的参数上

  @ResponseBody

  该注解用于将Controller的方法返回的对象,通过适当的HttpMessageConverter转换为指定格式后,写入到Response对象的body数据区

  @ModelAttribute    

  在方法定义上使用 @ModelAttribute 注解:Spring MVC 在调用目标处理方法前,会先逐个调用在方法级上标注了@ModelAttribute 的方法

  在方法的入参前使用 @ModelAttribute 注解:可以从隐含对象中获取隐含的模型数据中获取对象,再将请求参数 –绑定到对象中,再传入入参将方法入参对象添加到模型中

  @RequestParam 

  在处理方法入参处使用 @RequestParam 可以把请求参 数传递给请求方法

  @PathVariable

  绑定 URL 占位符到入参

  @ExceptionHandler

  注解到方法上,出现异常时会执行该方法

  @ControllerAdvice

  使一个Contoller成为全局的异常处理类,类中用@ExceptionHandler方法注解的方法可以处理所有Controller发生的异常

 四、自动匹配参数


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//match automatically

@RequestMapping("/person")

public String toPerson(String name,double age){

    System.out.println(name+" "+age);

    return "hello";

}

 五、自动装箱

  1.编写一个Person实体类


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package test.SpringMVC.model;

public class Person {

    public String getName() {

        return name;

    }

    public void setName(String name) {

        this.name = name;

    }

    public int getAge() {

        return age;

    }

    public void setAge(int age) {

        this.age = age;

    }

    private String name;

    private int age;

    

}

  2.在Controller里编写方法


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//boxing automatically

@RequestMapping("/person1")

public String toPerson(Person p){

    System.out.println(p.getName()+" "+p.getAge());

    return "hello";

}

 六、使用InitBinder来处理Date类型的参数


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//the parameter was converted in initBinder

@RequestMapping("/date")

public String date(Date date){

    System.out.println(date);

    return "hello";

}

   

//At the time of initialization,convert the type "String" to type "date"

@InitBinder

public void initBinder(ServletRequestDataBinder binder){

    binder.registerCustomEditor(Date.class, new CustomDateEditor(new SimpleDateFormat("yyyy-MM-dd"),

            true));

}

 七、向前台传递参数


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//pass the parameters to front-end

@RequestMapping("/show")

public String showPerson(Map<String,Object> map){

    Person p =new Person();

    map.put("p", p);

    p.setAge(20);

    p.setName("jayjay");

    return "show";

}

  前台可在Request域中取到"p"

 八、使用Ajax调用


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//pass the parameters to front-end using ajax

@RequestMapping("/getPerson")

public void getPerson(String name,PrintWriter pw){

    pw.write("hello,"+name);       

}

@RequestMapping("/name")

public String sayHello(){

    return "name";

}

  前台用下面的Jquery代码调用


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$(function(){

    $("#btn").click(function(){

       $.post("mvc/getPerson",{name:$("#name").val()},function(data){

            alert(data);

        });

    });

});

 九、在Controller中使用redirect方式处理请求


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//redirect

@RequestMapping("/redirect")

public String redirect(){

    return "redirect:hello";

}

 十、文件上传

  1.需要导入两个jar包

  2.在SpringMVC配置文件中加入


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<!-- upload settings -->

<bean id="multipartResolver"  class="org.springframework.web.multipart.commons.CommonsMultipartResolver">

    <property name="maxUploadSize" value="102400000"></property>

</bean>

  3.方法代码


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@RequestMapping(value="/upload",method=RequestMethod.POST)

public String upload(HttpServletRequest req) throws Exception{

    MultipartHttpServletRequest mreq = (MultipartHttpServletRequest)req;

    MultipartFile file = mreq.getFile("file");

    String fileName = file.getOriginalFilename();

    SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");       

    FileOutputStream fos = new FileOutputStream(req.getSession().getServletContext().getRealPath("/")+

            "upload/"+sdf.format(new Date())+fileName.substring(fileName.lastIndexOf(‘.‘)));

    fos.write(file.getBytes());

    fos.flush();

    fos.close();

    

    return "hello";

}

  4.前台form表单


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<form action="mvc/upload" method="post" enctype="multipart/form-data">

    <input type="file" name="file"><br>

    <input type="submit" value="submit">

</form>

 十一、使用@RequestParam注解指定参数的name


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@Controller

@RequestMapping("/test")

public class mvcController1 {

    @RequestMapping(value="/param")

    public String testRequestParam(@RequestParam(value="id") Integer id,

            @RequestParam(value="name")String name){

        System.out.println(id+" "+name);

        return "/hello";

    }   

}

 十二、RESTFul风格的SringMVC

  1.RestController


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@Controller

@RequestMapping("/rest")

public class RestController {

    @RequestMapping(value="/user/{id}",method=RequestMethod.GET)

    public String get(@PathVariable("id") Integer id){

        System.out.println("get"+id);

        return "/hello";

    }

    

    @RequestMapping(value="/user/{id}",method=RequestMethod.POST)

    public String post(@PathVariable("id") Integer id){

        System.out.println("post"+id);

        return "/hello";

    }

    

    @RequestMapping(value="/user/{id}",method=RequestMethod.PUT)

    public String put(@PathVariable("id") Integer id){

        System.out.println("put"+id);

        return "/hello";

    }

    

    @RequestMapping(value="/user/{id}",method=RequestMethod.DELETE)

    public String delete(@PathVariable("id") Integer id){

        System.out.println("delete"+id);

        return "/hello";

    }

    

}

  2.form表单发送put和delete请求

  在web.xml中配置


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<!-- configure the HiddenHttpMethodFilter,convert the post method to put or delete -->

<filter>

    <filter-name>HiddenHttpMethodFilter</filter-name>

    <filter-class>org.springframework.web.filter.HiddenHttpMethodFilter</filter-class>

</filter>

<filter-mapping>

    <filter-name>HiddenHttpMethodFilter</filter-name>

    <url-pattern>/*</url-pattern>

</filter-mapping>

  在前台可以用以下代码产生请求


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<form action="rest/user/1" method="post">

    <input type="hidden" name="_method" value="PUT">

    <input type="submit" value="put">

</form>

<form action="rest/user/1" method="post">

    <input type="submit" value="post">

</form>

<form action="rest/user/1" method="get">

    <input type="submit" value="get">

</form>

<form action="rest/user/1" method="post">

    <input type="hidden" name="_method" value="DELETE">

    <input type="submit" value="delete">

</form>

 十三、返回json格式的字符串

  1.导入以下jar包

  2.方法代码


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@Controller

@RequestMapping("/json")

public class jsonController {

    

    @ResponseBody

    @RequestMapping("/user")

    public  User get(){

        User u = new User();

        u.setId(1);

        u.setName("jayjay");

        u.setBirth(new Date());

        return u;

    }

}

 十四、异常的处理

  1.处理局部异常(Controller内)


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@ExceptionHandler

public ModelAndView exceptionHandler(Exception ex){

    ModelAndView mv = new ModelAndView("error");

    mv.addObject("exception", ex);

    System.out.println("in testExceptionHandler");

    return mv;

}

   

@RequestMapping("/error")

public String error(){

    int i = 5/0;

    return "hello";

}

  2.处理全局异常(所有Controller)


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@ControllerAdvice

public class testControllerAdvice {

    @ExceptionHandler

    public ModelAndView exceptionHandler(Exception ex){

        ModelAndView mv = new ModelAndView("error");

        mv.addObject("exception", ex);

        System.out.println("in testControllerAdvice");

        return mv;

    }

}

  3.另一种处理全局异常的方法

  在SpringMVC配置文件中配置


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<!-- configure SimpleMappingExceptionResolver -->

<bean class="org.springframework.web.servlet.handler.SimpleMappingExceptionResolver">

    <property name="exceptionMappings">

        <props>

            <prop key="java.lang.ArithmeticException">error</prop>

        </props>

    </property>

</bean>

  error是出错页面

 十五、设置一个自定义拦截器

  1.创建一个MyInterceptor类,并实现HandlerInterceptor接口


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public class MyInterceptor implements HandlerInterceptor {

    @Override

    public void afterCompletion(HttpServletRequest arg0,

            HttpServletResponse arg1, Object arg2, Exception arg3)

            throws Exception {

        System.out.println("afterCompletion");

    }

    @Override

    public void postHandle(HttpServletRequest arg0, HttpServletResponse arg1,

            Object arg2, ModelAndView arg3) throws Exception {

        System.out.println("postHandle");

    }

    @Override

    public boolean preHandle(HttpServletRequest arg0, HttpServletResponse arg1,

            Object arg2) throws Exception {

        System.out.println("preHandle");

        return true;

    }

}

  2.在SpringMVC的配置文件中配置


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<!-- interceptor setting -->

<mvc:interceptors>

    <mvc:interceptor>

        <mvc:mapping path="/mvc/**"/>

        <bean class="test.SpringMVC.Interceptor.MyInterceptor"></bean>

    </mvc:interceptor>       

</mvc:interceptors>

  3.拦截器执行顺序

 十六、表单的验证(使用Hibernate-validate)及国际化

  1.导入Hibernate-validate需要的jar包

(未选中不用导入)

  2.编写实体类User并加上验证注解


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public class User {

    public int getId() {

        return id;

    }

    public void setId(int id) {

        this.id = id;

    }

    public String getName() {

        return name;

    }

    public void setName(String name) {

        this.name = name;

    }

    public Date getBirth() {

        return birth;

    }

    public void setBirth(Date birth) {

        this.birth = birth;

    }

    @Override

    public String toString() {

        return "User [id=" + id + ", name=" + name + ", birth=" + birth + "]";

    }   

    private int id;

    @NotEmpty

    private String name;

    @Past

    @DateTimeFormat(pattern="yyyy-MM-dd")

    private Date birth;

}

  ps:@Past表示时间必须是一个过去值

  3.在jsp中使用SpringMVC的form表单


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<form:form action="form/add" method="post" modelAttribute="user">

    id:<form:input path="id"/><form:errors path="id"/><br>

    name:<form:input path="name"/><form:errors path="name"/><br>

    birth:<form:input path="birth"/><form:errors path="birth"/>

    <input type="submit" value="submit">

</form:form>

  ps:path对应name

  4.Controller中代码


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@Controller

@RequestMapping("/form")

public class formController {

    @RequestMapping(value="/add",method=RequestMethod.POST)   

    public String add(@Valid User u,BindingResult br){

        if(br.getErrorCount()>0){           

            return "addUser";

        }

        return "showUser";

    }

    

    @RequestMapping(value="/add",method=RequestMethod.GET)

    public String add(Map<String,Object> map){

        map.put("user",new User());

        return "addUser";

    }

}

  ps:

  1.因为jsp中使用了modelAttribute属性,所以必须在request域中有一个"user".

  [email protected] 表示按照在实体上标记的注解验证参数

  3.返回到原页面错误信息回回显,表单也会回显

  5.错误信息自定义

  在src目录下添加locale.properties

NotEmpty.user.name=name can‘t not be empty
Past.user.birth=birth should be a past value
DateTimeFormat.user.birth=the format of input is wrong
typeMismatch.user.birth=the format of input is wrong
typeMismatch.user.id=the format of input is wrong

  在SpringMVC配置文件中配置


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<!-- configure the locale resource -->

<bean id="messageSource" class="org.springframework.context.support.ResourceBundleMessageSource">

    <property name="basename" value="locale"></property>

</bean>

  6.国际化显示

  在src下添加locale_zh_CN.properties

username=账号
password=密码

  locale.properties中添加

username=user name
password=password

  创建一个locale.jsp


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<body>

  <fmt:message key="username"></fmt:message>

  <fmt:message key="password"></fmt:message>

</body>

  在SpringMVC中配置


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<!-- make the jsp page can be visited -->

<mvc:view-controller path="/locale" view-name="locale"/>

  让locale.jsp在WEB-INF下也能直接访问

  最后,访问locale.jsp,切换浏览器语言,能看到账号和密码的语言也切换了

 十七、压轴大戏--整合SpringIOC和SpringMVC

  1.创建一个test.SpringMVC.integrate的包用来演示整合,并创建各类

  2.User实体类


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public class User {

    public int getId() {

        return id;

    }

    public void setId(int id) {

        this.id = id;

    }

    public String getName() {

        return name;

    }

    public void setName(String name) {

        this.name = name;

    }

    public Date getBirth() {

        return birth;

    }

    public void setBirth(Date birth) {

        this.birth = birth;

    }

    @Override

    public String toString() {

        return "User [id=" + id + ", name=" + name + ", birth=" + birth + "]";

    }   

    private int id;

    @NotEmpty

    private String name;

    @Past

    @DateTimeFormat(pattern="yyyy-MM-dd")

    private Date birth;

}

  3.UserService类


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@Component

public class UserService {

    public UserService(){

        System.out.println("UserService Constructor...\n\n\n\n\n\n");

    }

    

    public void save(){

        System.out.println("save");

    }

}

  4.UserController


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@Controller

@RequestMapping("/integrate")

public class UserController {

    @Autowired

    private UserService userService;

    

    @RequestMapping("/user")

    public String saveUser(@RequestBody @ModelAttribute User u){

        System.out.println(u);

        userService.save();

        return "hello";

    }

}

  5.Spring配置文件

  在src目录下创建SpringIOC的配置文件applicationContext.xml


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<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"

    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

    xsi:schemaLocation="http://www.springframework.org/schema/beans

        http://www.springframework.org/schema/beans/spring-beans.xsd

        http://www.springframework.org/schema/util

        http://www.springframework.org/schema/util/spring-util-4.0.xsd

        http://www.springframework.org/schema/context

        http://www.springframework.org/schema/context/spring-context.xsd

        "

        xmlns:util="http://www.springframework.org/schema/util"

        xmlns:p="http://www.springframework.org/schema/p"

        xmlns:context="http://www.springframework.org/schema/context"

        >

    <context:component-scan base-package="test.SpringMVC.integrate">

        <context:exclude-filter type="annotation"

            expression="org.springframework.stereotype.Controller"/>

        <context:exclude-filter type="annotation"

            expression="org.springframework.web.bind.annotation.ControllerAdvice"/>       

    </context:component-scan>

    

</beans>

  在Web.xml中添加配置


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<!-- configure the springIOC -->

<listener>

    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>

</listener>

<context-param

  <param-name>contextConfigLocation</param-name

  <param-value>classpath:applicationContext.xml</param-value>

</context-param>

  6.在SpringMVC中进行一些配置,防止SpringMVC和SpringIOC对同一个对象的管理重合


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<!-- scan the package and the sub package -->

    <context:component-scan base-package="test.SpringMVC.integrate">

        <context:include-filter type="annotation"

            expression="org.springframework.stereotype.Controller"/>

        <context:include-filter type="annotation"

            expression="org.springframework.web.bind.annotation.ControllerAdvice"/>

    </context:component-scan>

 十八、SpringMVC详细运行流程图

 十九、SpringMVC与struts2的区别

  1、springmvc基于方法开发的,struts2基于类开发的。springmvc将url和controller里的方法映射。映射成功后springmvc生成一个Handler对象,对象中只包括了一个method。方法执行结束,形参数据销毁。springmvc的controller开发类似web service开发。

  2、springmvc可以进行单例开发,并且建议使用单例开发,struts2通过类的成员变量接收参数,无法使用单例,只能使用多例。

  3、经过实际测试,struts2速度慢,在于使用struts标签,如果使用struts建议使用jstl。

时间: 2024-10-14 22:51:18

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