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 = "IT虾米网"
     xmlns:xsi = "IT虾米网"
     xmlns:context = "IT虾米网"
     xmlns:mvc = "IT虾米网"
     xsi:schemaLocation="IT虾米网 IT虾米网
         IT虾米网 IT虾米网
         IT虾米网 IT虾米网">                   
 
     <!-- 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".

  2.@Valid 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 = "IT虾米网"
     xmlns:xsi = "IT虾米网"
     xsi:schemaLocation="IT虾米网
         IT虾米网
         IT虾米网
         IT虾米网
         IT虾米网
         IT虾米网
         "
         xmlns:util = "IT虾米网"
         xmlns:p = "IT虾米网"
         xmlns:context = "IT虾米网"   
         >
     < 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。


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