SpringMVC简单使用教程
一、SpringMVC简单入门,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
1 <!--configure the setting of springmvcDispatcherServlet and configure the mapping--> 2 <servlet> 3 <servlet-name>springmvc</servlet-name> 4 <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> 5 <init-param> 6 <param-name>contextConfigLocation</param-name> 7 <param-value>classpath:springmvc-servlet.xml</param-value> 8 </init-param> 9 <!-- <load-on-startup>1</load-on-startup> --> 10 </servlet> 11 <servlet-mapping> 12 <servlet-name>springmvc</servlet-name> 13 <url-pattern>/</url-pattern> 14 </servlet-mapping>
3.在src下添加springmvc-servlet.xml配置文件
1 <?xml version="1.0" encoding="UTF-8"?> 2 <beans xmlns="http://www.springframework.org/schema/beans" 3 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 4 xmlns:context="http://www.springframework.org/schema/context" 5 xmlns:mvc="http://www.springframework.org/schema/mvc" 6 xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd 7 http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.1.xsd 8 http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.1.xsd"> 9 <!-- scan the package and the sub package --> 10 <context:component-scan base-package="test.SpringMVC"/> 11 <!-- don't handle the static resource --> 12 <mvc:default-servlet-handler /> 13 <!-- if you use annotation you must configure following setting --> 14 <mvc:annotation-driven /> 15 16 <!-- configure the InternalResourceViewResolver --> 17 <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" 18 id="internalResourceViewResolver"> 19 <!-- 前缀 --> 20 <property name="prefix" value="/WEB-INF/jsp/" /> 21 <!-- 后缀 --> 22 <property name="suffix" value=".jsp" /> 23 </bean> 24 </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
1 @Controller 2 @RequestMapping("/mvc") 3 public class mvcController { 4 @RequestMapping("/hello") 5 public String hello(){ 6 return "hello"; 7 } 8 }
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
1 //match automatically 2 @RequestMapping("/person") 3 public String toPerson(String name,double age){ 4 System.out.println(name+" "+age); 5 return "hello"; 6 }
五、自动装箱
1.编写一个Person实体类
1 package test.SpringMVC.model; 2 public class Person { 3 public String getName() { 4 return name; 5 } 6 public void setName(String name) { 7 this.name = name; 8 } 9 public int getAge() { 10 return age; 11 } 12 public void setAge(int age) { 13 this.age = age; 14 } 15 private String name; 16 private int age; 17 18 }
2.在Controller里编写方法
1 //boxing automatically 2 @RequestMapping("/person1") 3 public String toPerson(Person p){ 4 System.out.println(p.getName()+" "+p.getAge()); 5 return "hello"; 6 }
六、使用InitBinder来处理Date类型的参数
1 //the parameter was converted in initBinder 2 @RequestMapping("/date") 3 public String date(Date date){ 4 System.out.println(date); 5 return "hello"; 6 } 7 8 //At the time of initialization,convert the type "String" to type "date" 9 @InitBinder 10 public void initBinder(ServletRequestDataBinder binder){ 11 binder.registerCustomEditor(Date.class, new CustomDateEditor(new SimpleDateFormat("yyyy-MM-dd"), 12 true)); 13 }
七、向前台传递参数
1 //pass the parameters to front-end 2 @RequestMapping("/show") 3 public String showPerson(Map<String,Object> map){ 4 Person p =new Person(); 5 map.put("p", p); 6 p.setAge(20); 7 p.setName("jayjay"); 8 return "show"; 9 }
八、使用Ajax调用
1 //pass the parameters to front-end using ajax 2 @RequestMapping("/getPerson") 3 public void getPerson(String name,PrintWriter pw){ 4 pw.write("hello,"+name); 5 } 6 @RequestMapping("/name") 7 public String sayHello(){ 8 return "name"; 9 }
1 $(function(){ 2 $("#btn").click(function(){ 3 $.post("mvc/getPerson",{name:$("#name").val()},function(data){ 4 alert(data); 5 }); 6 }); 7 });
九、在Controller中使用redirect方式处理请求
1 //redirect 2 @RequestMapping("/redirect") 3 public String redirect(){ 4 return "redirect:hello"; 5 }
十、文件上传
1.需要导入两个jar包
2.在SpringMVC配置文件中加入
1 <!-- upload settings --> 2 <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"> 3 <property name="maxUploadSize" value="102400000"></property> 4 </bean>
3.方法代码
1 @RequestMapping(value="/upload",method=RequestMethod.POST) 2 public String upload(HttpServletRequest req) throws Exception{ 3 MultipartHttpServletRequest mreq = (MultipartHttpServletRequest)req; 4 MultipartFile file = mreq.getFile("file"); 5 String fileName = file.getOriginalFilename(); 6 SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss"); 7 FileOutputStream fos = new FileOutputStream(req.getSession().getServletContext().getRealPath("/")+ 8 "upload/"+sdf.format(new Date())+fileName.substring(fileName.lastIndexOf('.'))); 9 fos.write(file.getBytes()); 10 fos.flush(); 11 fos.close(); 12 13 return "hello"; 14 }
4.前台form表单
1 <form action="mvc/upload" method="post" enctype="multipart/form-data"> 2 <input type="file" name="file"><br> 3 <input type="submit" value="submit"> 4 </form>
十一、使用@RequestParam注解指定参数的name
1 @Controller 2 @RequestMapping("/test") 3 public class mvcController1 { 4 @RequestMapping(value="/param") 5 public String testRequestParam(@RequestParam(value="id") Integer id, 6 @RequestParam(value="name")String name){ 7 System.out.println(id+" "+name); 8 return "/hello"; 9 } 10 }
十二、Restful风格的SringMVC
1.RestController
1 @Controller 2 @RequestMapping("/rest") 3 public class RestController { 4 @RequestMapping(value="/user/{id}",method=RequestMethod.GET) 5 public String get(@PathVariable("id") Integer id){ 6 System.out.println("get"+id); 7 return "/hello"; 8 } 9 10 @RequestMapping(value="/user/{id}",method=RequestMethod.POST) 11 public String post(@PathVariable("id") Integer id){ 12 System.out.println("post"+id); 13 return "/hello"; 14 } 15 16 @RequestMapping(value="/user/{id}",method=RequestMethod.PUT) 17 public String put(@PathVariable("id") Integer id){ 18 System.out.println("put"+id); 19 return "/hello"; 20 } 21 22 @RequestMapping(value="/user/{id}",method=RequestMethod.DELETE) 23 public String delete(@PathVariable("id") Integer id){ 24 System.out.println("delete"+id); 25 return "/hello"; 26 } 27 28 }
2.form表单发送put和delete请求
在web.xml中配置:
1 <!-- configure the HiddenHttpMethodFilter,convert the post method to put or delete --> 2 <filter> 3 <filter-name>HiddenHttpMethodFilter</filter-name> 4 <filter-class>org.springframework.web.filter.HiddenHttpMethodFilter</filter-class> 5 </filter> 6 <filter-mapping> 7 <filter-name>HiddenHttpMethodFilter</filter-name> 8 <url-pattern>/*</url-pattern> 9 </filter-mapping>
在前台的请求:
1 <form action="rest/user/1" method="post"> 2 <input type="hidden" name="_method" value="PUT"> 3 <input type="submit" value="put"> 4 </form> 5 6 <form action="rest/user/1" method="post"> 7 <input type="submit" value="post"> 8 </form> 9 10 <form action="rest/user/1" method="get"> 11 <input type="submit" value="get"> 12 </form> 13 14 <form action="rest/user/1" method="post"> 15 <input type="hidden" name="_method" value="DELETE"> 16 <input type="submit" value="delete"> 17 </form>
十三、返回json格式的字符串
1.导入以下jar包
2.方法代码
1 @Controller 2 @RequestMapping("/json") 3 public class jsonController { 4 5 @ResponseBody 6 @RequestMapping("/user") 7 public User get(){ 8 User u = new User(); 9 u.setId(1); 10 u.setName("jayjay"); 11 u.setBirth(new Date()); 12 return u; 13 } 14 }
十四、异常的处理
1.处理局部异常(Controller内)
1 @ExceptionHandler 2 public ModelAndView exceptionHandler(Exception ex){ 3 ModelAndView mv = new ModelAndView("error"); 4 mv.addObject("exception", ex); 5 System.out.println("in testExceptionHandler"); 6 return mv; 7 } 8 9 @RequestMapping("/error") 10 public String error(){ 11 int i = 5/0; 12 return "hello"; 13 }
2.处理全局异常(所有Controller)
1 @ControllerAdvice 2 public class testControllerAdvice { 3 @ExceptionHandler 4 public ModelAndView exceptionHandler(Exception ex){ 5 ModelAndView mv = new ModelAndView("error"); 6 mv.addObject("exception", ex); 7 System.out.println("in testControllerAdvice"); 8 return mv; 9 } 10 }
3.另一种处理全局异常的方法
在SpringMVC配置文件中配置:
1 <!-- configure SimpleMappingExceptionResolver --> 2 <bean class="org.springframework.web.servlet.handler.SimpleMappingExceptionResolver"> 3 <property name="exceptionMappings"> 4 <props> 5 <prop key="java.lang.ArithmeticException">error</prop> 6 </props> 7 </property> 8 </bean>
说明: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
1 public class MyInterceptor implements HandlerInterceptor { 2 @Override 3 public void afterCompletion(HttpServletRequest arg0, 4 HttpServletResponse arg1, Object arg2, Exception arg3) 5 throws Exception { 6 System.out.println("afterCompletion"); 7 } 8 @Override 9 public void postHandle(HttpServletRequest arg0, HttpServletResponse arg1, 10 Object arg2, ModelAndView arg3) throws Exception { 11 System.out.println("postHandle"); 12 } 13 @Override 14 public boolean preHandle(HttpServletRequest arg0, HttpServletResponse arg1, 15 Object arg2) throws Exception { 16 System.out.println("preHandle"); 17 return true; 18 } 19 }
2.在SpringMVC的配置文件中配置
1 <!-- interceptor setting --> 2 <mvc:interceptors> 3 <mvc:interceptor> 4 <mvc:mapping path="/mvc/**"/> 5 <bean class="test.SpringMVC.Interceptor.MyInterceptor"></bean> 6 </mvc:interceptor> 7 </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
2.编写实体类User并加上验证注解
1 public class User { 2 public int getId() { 3 return id; 4 } 5 public void setId(int id) { 6 this.id = id; 7 } 8 public String getName() { 9 return name; 10 } 11 public void setName(String name) { 12 this.name = name; 13 } 14 public Date getBirth() { 15 return birth; 16 } 17 public void setBirth(Date birth) { 18 this.birth = birth; 19 } 20 @Override 21 public String toString() { 22 return "User [id=" + id + ", name=" + name + ", birth=" + birth + "]"; 23 } 24 private int id; 25 @NotEmpty 26 private String name; 27 @Past 28 @DateTimeFormat(pattern="yyyy-MM-dd") 29 private Date birth; 30 }
说明:@Past表示时间必须是一个过去值
3.在jsp中使用SpringMVC的form表单
1 <form:form action="form/add" method="post" modelAttribute="user"> 2 id:<form:input path="id"/><form:errors path="id"/><br> 3 name:<form:input path="name"/><form:errors path="name"/><br> 4 birth:<form:input path="birth"/><form:errors path="birth"/> 5 <input type="submit" value="submit"> 6 </form:form>
说明:path对应name
4.Controller中代码
1 @Controller 2 @RequestMapping("/form") 3 public class formController { 4 @RequestMapping(value="/add",method=RequestMethod.POST) 5 public String add(@Valid User u,BindingResult br){ 6 if(br.getErrorCount()>0){ 7 return "addUser"; 8 } 9 return "showUser"; 10 } 11 12 @RequestMapping(value="/add",method=RequestMethod.GET) 13 public String add(Map<String,Object> map){ 14 map.put("user",new User()); 15 return "addUser"; 16 } 17 }
补充:
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
1 NotEmpty.user.name=name can't not be empty 2 Past.user.birth=birth should be a past value 3 DateTimeFormat.user.birth=the format of input is wrong 4 typeMismatch.user.birth=the format of input is wrong 5 typeMismatch.user.id=the format of input is wrong
在SpringMVC配置文件中配置
1 <!-- configure the locale resource --> 2 <bean id="messageSource" class="org.springframework.context.support.ResourceBundleMessageSource"> 3 <property name="basename" value="locale"></property> 4 </bean>
6.国际化显示
在src下添加locale_zh_CN.properties
1 username=账号 2 password=密码
locale.properties中添加
1 username=username 2 password=password
创建一个locale.jsp
1 <body> 2 <fmt:message key="username"></fmt:message> 3 <fmt:message key="password"></fmt:message> 4 </body>
在SpringMVC中配置
1 <!-- make the jsp page can be visited --> 2 <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、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
1 public class User { 2 public int getId() { 3 return id; 4 } 5 public void setId(int id) { 6 this.id = id; 7 } 8 public String getName() { 9 return name; 10 } 11 public void setName(String name) { 12 this.name = name; 13 } 14 public Date getBirth() { 15 return birth; 16 } 17 public void setBirth(Date birth) { 18 this.birth = birth; 19 } 20 @Override 21 public String toString() { 22 return "User [id=" + id + ", name=" + name + ", birth=" + birth + "]"; 23 } 24 private int id; 25 @NotEmpty 26 private String name; 27 @Past 28 @DateTimeFormat(pattern="yyyy-MM-dd") 29 private Date birth; 30 }
3.UserService类
1 @Component 2 public class UserService { 3 public UserService(){ 4 System.out.println("UserService Constructor...\n\n\n\n\n\n"); 5 } 6 7 public void save(){ 8 System.out.println("save"); 9 } 10 }
4.UserController类
1 @Controller 2 @RequestMapping("/integrate") 3 public class UserController { 4 @Autowired 5 private UserService userService; 6 7 @RequestMapping("/user") 8 public String saveUser(@RequestBody @ModelAttribute User u){ 9 System.out.println(u); 10 userService.save(); 11 return "hello"; 12 } 13 }
5.Spring配置文件
在src目录下创建SpringIOC的配置文件applicationContext.xml
1 <?xml version="1.0" encoding="UTF-8"?> 2 <beans xmlns="http://www.springframework.org/schema/beans" 3 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 4 xsi:schemaLocation="http://www.springframework.org/schema/beans 5 http://www.springframework.org/schema/beans/spring-beans.xsd 6 http://www.springframework.org/schema/util 7 http://www.springframework.org/schema/util/spring-util-4.0.xsd 8 http://www.springframework.org/schema/context 9 http://www.springframework.org/schema/context/spring-context.xsd 10 " 11 xmlns:util="http://www.springframework.org/schema/util" 12 xmlns:p="http://www.springframework.org/schema/p" 13 xmlns:context="http://www.springframework.org/schema/context" 14 > 15 <context:component-scan base-package="test.SpringMVC.integrate"> 16 <context:exclude-filter type="annotation" 17 expression="org.springframework.stereotype.Controller"/> 18 <context:exclude-filter type="annotation" 19 expression="org.springframework.web.bind.annotation.ControllerAdvice"/> 20 </context:component-scan> 21 22 </beans>
在web.xml中添加配置
1 <!-- configure the springIOC --> 2 <listener> 3 <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> 4 </listener> 5 <context-param> 6 <param-name>contextConfigLocation</param-name> 7 <param-value>classpath:applicationContext.xml</param-value> 8 </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
1 <!-- scan the package and the sub package --> 2 <context:component-scan base-package="test.SpringMVC.integrate"> 3 <context:include-filter type="annotation" 4 expression="org.springframework.stereotype.Controller"/> 5 <context:include-filter type="annotation" 6 expression="org.springframework.web.bind.annotation.ControllerAdvice"/> 7 </context:component-scan>
十八、SpringMVC详细运行流程图
十九、SpringMVC运行原理
1. 客户端请求提交到DispatcherServlet
2. 由DispatcherServlet控制器查询一个或多个HandlerMapping,找到处理请求的Controller
3. DispatcherServlet将请求提交到Controller
4. Controller调用业务逻辑处理后,返回ModelAndView
5. DispatcherServlet查询一个或多个ViewResoler视图解析器,找到ModelAndView指定的视图
6. 视图负责将结果显示到客户端
二十、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。