springmvc

作者: 呦後 | 来源:发表于2017-06-19 20:35 被阅读0次

    springMVC

    SpringMVC:前端控制器,映射器,适配器,控制器,试图解析器

    前端控制器

    前端控制器在web.xml中配置

      
      <servlet>
      <!-- 命名 -->
        <servlet-name>springmvc</servlet-name>
        <!-- 加载包中的前端控制器 -->
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <!-- 让服务器已启动就开始加载文件springMVC.xml,用的是contextConfigLocation这个属性 -->
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:springMVC.xml</param-value>
        </init-param> 
            <!-- 启动加载 -->
        <load-on-startup>1</load-on-startup> 
      </servlet>
      
      <servlet-mapping>
      <!-- 对应上面的命名 -->
        <servlet-name>springmvc</servlet-name>
        <!-- 对文件进行拦截来执行上面的程序, "/"代表拦截所有的-->
        <url-pattern>/</url-pattern>
      </servlet-mapping>
      
    

    两种映射器

        <!-- 映射器 -->                    
       <bean class="org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping"></bean>
       <!-- 映射器2 -->
       <bean class=" org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">
            <property name="mappings">
                <props>
                <!-- 这里的值要和控制器中的id相对应 -->
                    <prop key="/text1">text</prop>
                    <prop key="/text1">text</prop>
                </props>
            </property>
       </bean>
    
    
    

    两种适配器

       <!-- 适配器  要实现Controller接口-->
       <bean class="org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter"></bean>
       <!-- 适配器2 要实现 HttpRequestHandler接口 -->
       <bean class=" org.springframework.web.servlet.mvc.HttpRequestHandlerAdapter"></bean>
    

    控制器

       <!-- 控制器 -->
       <bean class="com.hemi.controller.MyController"  name="/text" id="text"></bean>
    
    public class MyController implements org.springframework.web.servlet.mvc.Controller{
    
        @Override
        public ModelAndView handleRequest(HttpServletRequest req, HttpServletResponse resp) throws Exception {      
            String username = req.getParameter("username");
            String password = req.getParameter("password");
    //      req.setAttribute("username", username);
    //      req.setAttribute("password", password);
            ModelAndView view = new ModelAndView();
            if("lisi".equals(username)&&"123".equals(password)){
                view.setViewName("Hello.jsp");
            }
            else{
                view.setViewName("login.jsp");
            }
                    
            return view;
        }
    
    }
    

    视图解析器

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

    视图解析器的配置前缀后缀

       <!-- 视图解析器 -->
       <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
       <!-- 前缀 -->
       <property name="prefix" value="/"></property>
       <!-- 后缀 -->
       <property name="suffix" value=".jsp"></property>
       </bean>
        
    

    注解适配器和映射器

    注解适配器和映射器要一起使用才有效

         <!-- 扫描包 -->
       <context:component-scan base-package="com.hemi.controller"></context:component-scan>
    
    
       <!-- 配置注解 1-->
            <!-- 配置映射器注解 -->
       <bean class=" org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping "></bean>
            <!-- 配置适配器注解 -->
       <bean class=" org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter"></bean>
    
        <!--配置注解2-->
        <!-- 终极替换上面的注解 -->
        <mvc:annotation-driven></mvc:annotation-driven>
    

    Controller里使用注解

    @Controller
    public class TextControler{
        @RequestMapping(show1)
        public ModelAndView show1(){}
    }
    

    cotroller里面返回数据

    ModleAndView类型返回值 返回值用一般用view保存使用 view.addObject方法(域对象也可以)

        @RequestMapping("show1")
        public ModelAndView show1(HttpServletRequest req){
            String username = req.getParameter("username");
            String password = req.getParameter("password");
            ModelAndView view = new ModelAndView();
            view.addObject("username", username);
            view.addObject("password", password);       
            view.setViewName("Hello");
            return view;        
        }
    

    String类型返回值返回数据可以域对象,Modle以及ModleMap来保存数据

        @RequestMapping("show2")
        public String show2(Model model,HttpServletRequest req){
            String username = req.getParameter("username");
            String password = req.getParameter("password");
            model.addAttribute("username", username);
            model.addAttribute("password", password);
            return "Hello";     
        }
    

    void类型返回值要用域对象来保存数据

        @RequestMapping("show3")
        public void show3(HttpServletRequest req,HttpServletResponse resp){
            String username = req.getParameter("username");
            String password = req.getParameter("password");
            req.setAttribute("username", username);
            req.setAttribute("password", password);
            try {
                req.getRequestDispatcher("Hello.jsp").forward(req, resp);
            } catch (ServletException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    

    参数绑定

    简单参数绑定 pojo参数绑定,自定义类型

    简单参数绑定:传入的数据和jsp中写入request中的数据参数相同,如果想用形参则使用注解@RequestParam("username")是取值 String name是取得别名

    Pojo参数绑定:定义一个实体类和jsp中放入的数据类型相同,然后传入实体类可以获得参数

    自定义类型: 创建一个转换类实现Converter<String, Date>接口 重写里面的方法进行转换,在springMVC.xml中配置将org.springframework.format.support.FormattingConversionServiceFactoryBean类引入里面注入转换类,在注解驱动的属性中用conversion-service将配置的类加载驱动中,在实体类需要转换类型的字段(日期)上面添加 @DateTimeFormat(pattern="yyyy-MM-dd")

    自定义转换类:

    public class DateConvert implements Converter<String, Date>{
    
        @Override
        public Date convert(String source) {
            SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
            try {
                return format.parse(source);
            } catch (ParseException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return null;
        }
    
    }
    

    springMVC中配置

        <mvc:annotation-driven conversion-service="conversionService">          
        </mvc:annotation-driven>
            
        <bean id="conversionService" class="org.springframework.format.support.FormattingConversionServiceFactoryBean">
            <property name="converters">
                <list>
                    <bean class="com.hemi.controller.convert.DateConvert"></bean>
                </list>         
            </property>
            
        </bean>
    

    User实体类中配置

     private String username;
     private String password;
     @DateTimeFormat(pattern="yyyy-MM-dd")
     private Date date;
    

    控制器:

        @RequestMapping("show4")
        public String show4(Model model,User user){
            model.addAttribute("user", user);
            return "Hello";     
        }
    }
    

    参数绑定-数组,包装数据类型 list集合

    login.jsp:

        <form action="show5" method="post">
            用户名:<input type="text" name="username"><br> 
            密码:<input type="password" name="password"> <br>
            日期<input type="text" name="date"><br>
            <!--传递list集合中装的是多个地址对象-->
            <input type="text" placeholder="请输入地址" name="add[0].addres"><br> 
            <input type="text" placeholder="请输入编码" name="add[0].code"><br> 
            <input type="text" placeholder="请输入地址" name="add[1].addres"><br> 
            <input type="text" placeholder="请输入编码" name="add[1].code"><br> 
            <!--传递单个地址的实体对象-->
            <input type="text" placeholder="请输入地址" name="add.addres"><br> 
            <input type="text" placeholder="请输入编码" name="add.code"><br> 
            <!--传递一个数组-->
            <input type="checkbox" name="hobby" value="basketball">篮球<br>
            <input type="checkbox" name="hobby" value="football">篮球<br>
            <input type="checkbox" name="hobby" value="tennis">网球
            <input type="submit" value="登录">
        </form>
    

    user类:

     private String username;
     private String password;
     @DateTimeFormat(pattern="yyyy-MM-dd")
     private Date date;
     private List<Address> add;
     private String[] hobby;
    

    控制器:

        @RequestMapping("show5")
        public String show5(Model model,User user){
            model.addAttribute("user", user);
            return "Hello";     
        }
    

    全局异常处理开发:

    1、自定义异常类
    2、自定义异常处理器实现 HandlerExceptionResolver接口
    3、在springmvc配置文件中配置全局异常控制器

    自定义异常类:

    public class CustomException extends Exception{
        private String msg;
            
        public CustomException(String msg) {
            super(msg);
            this.msg = msg;
        }
    
        public String getMsg() {
            return msg;
        }
    
        public void setMsg(String msg) {
            this.msg = msg;
        }
        
        
        
    }
    

    自定义异常处理器:

    public class ExceptionHandler implements HandlerExceptionResolver{
    
        @Override
        public ModelAndView resolveException(HttpServletRequest req, HttpServletResponse resp, Object object,
                Exception ex) {
            CustomException customException=null;
            if (ex instanceof CustomException) {
                customException=(CustomException)ex;
            }else{
                customException=new CustomException("未知错误");
            }
            ModelAndView view = new ModelAndView();
            view.addObject("error", customException);
            view.setViewName("error");
            return view;
        }
    
    }
    

    springMVC的配置

    <!-- 定义全局异常 -->
        <bean class="com.hemi.exception.handler.ExceptionHandler"></bean>
    

    静态资源的释放

    在配置文件中进行配置

        <!-- 静态资源释放-->
        <mvc:resources location="/image/" mapping="/image/*.*"></mvc:resources>
    

    文件上传的步骤

    1、编写配置文件

        <!-- 配置文件上传处理 -->
        <bean id="multipartResolver"
            class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
            <property name="defaultEncoding" value="utf-8"></property>
            <property name="maxUploadSize" value="10485760000"></property>
            <property name="maxInMemorySize" value="40960"></property>
        </bean>
    

    2、编写控制器
    上传单个文件:

        public String upload(MultipartFile file,HttpServletRequest req) throws IllegalStateException, IOException{
            if(file==null){
                return "uploadFile";            
            }
            //取出文件名
            String filename = file.getOriginalFilename();
            //根据文件的虚拟入境找到真实入境
            String path = req.getServletContext().getRealPath("/temp");
              File file2 = new File(path);
              if (!file2.exists()) {
                //创建目录
                file2.mkdirs();
            }
              //将传入的文件按照真实入境和文件名写出来
            file.transferTo(new File(file2,filename));
            return "success";       
        }
    

    批量上传文件

        @RequestMapping("/upload1")
        public String upload1(MultipartFile[] file,HttpServletRequest req) throws IllegalStateException, IOException{
            if (file.length==0) {
                return "uploadFile";
            }
            for (MultipartFile multipartFile : file) {
                String filename = multipartFile.getOriginalFilename();
                String realPath = req.getServletContext().getRealPath("/team");
                File file2 = new File(realPath);
                if (!file2.exists()) {
                    file2.mkdirs();
                }
                multipartFile.transferTo(new File(file2,filename));         
            }
            return "success";
        }
    

    3、编写前端表单页面
    注意:把form表单的默认的enctype 类型改成 enctype="multipart/form-data"

        <form action="upload" method="post" enctype="multipart/form-data">
        请上传文件:<input type="file" name="file">
            <br>
            <input type="submit" value="upload">
        </form> 
        <hr>
        <form action="upload1" method="post" enctype="multipart/form-data">
        请上传文件:<input type="file" name="file">
            <br>
            请上传文件:<input type="file" name="file">
            <br>
            <input type="submit" value="upload1">
        </form> 
    

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