• SpringMVC入门

    一、 什么是springMVC?
    Spring Web MVC是一种基于Java的实现了MVC设计模式的、请求驱动类型的、轻量级Web框架。


    二、 SpringMVC处理请求的流程
    1 首先用户发送请求-->DispatherServlet
    2 DispatcherServlet-->HandlerMapping
    3 DispatcherServlet-->HandlerAdapter
    4 HandlerAdapter-->处理器功能处理方法的调用
    5 ModelAndView的逻辑视图名-->ViewRecolver
    6 View-->渲染
    7 返回控制权给DispatcherServlet，由DispatcherServlet返回呼应给用户，流程结束


    三、 SpringMVC核心开发步骤
    1 DispatcherServlet在web.xml中的部署描述，从而拦截请求到springMVC
    2 HandlerMapping的配置，从而将请求映射到处理器
    3 HandlerAdapter的配置，从而支持多种类型的处理器
    4 处理器(页面控制器)的配置，从而刊行功能处理
    5 ViewResolver的配置，从而将逻辑视图名解析为具体的视图技术


    四、 SpringMVC的组件
    1 前端控制器(DispatcherServlet)
    2 请求到处理器映射(HandlerMapping)
    3 处理器适配器(HandlerAdapter)
    4 视图解析器(ViewResolver)
    5 处理器或页面控制器(Controller)
    6 验证器(Validator)
    6 命令对象(Command 请求参数绑定到的对象就叫命令对象)
    7 表单对象(Form Object提供给表单展示和提交到的对象就叫表单对象)


    五、 如何在项目中添加springmvc

    1.添加pom依赖

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>${spring.version}</version>
      </dependency>
    <dependency>
          <groupId>jstl</groupId>
          <artifactId>jstl</artifactId>
          <version>1.2</version>
      </dependency>
      <dependency>
          <groupId>taglibs</groupId>
          <artifactId>standard</artifactId>
          <version>1.1.2</version>
      </dependency>
    <tomcat-jsp-api.version>8.0.47</tomcat-jsp-api.version>

 <dependency>
      <groupId>org.apache.tomcat</groupId>
      <artifactId>tomcat-jsp-api</artifactId>
      <version>${tomcat-jsp-api.version}</version>
    </dependency>

    2 在WEB-INF下添加springmvc-servlet.xml(spring-mvc.xml)

    <?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" xmlns:aop="http://www.springframework.org/schema/aop"
       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-4.3.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd">
    <!-- 通过context:component-scan元素扫描指定包下的控制器-->
    <!--1) 扫描com.javaxl.zf及子子孙孙包下的控制器(扫描范围过大，耗时)-->
    <aop:aspectj-autoproxy/>
    <context:component-scan base-package="com.psy"/>

    <!--2) 此标签默认注册DefaultAnnotationHandlerMapping和AnnotationMethodHandlerAdapter -->
    <!--两个bean，这两个bean是spring MVC为@Controllers分发请求所必须的。并提供了数据绑定支持，-->
    <!--@NumberFormatannotation支持，@DateTimeFormat支持，@Valid支持，读写XML的支持（JAXB），读写JSON的支持（Jackson）-->
    <mvc:annotation-driven></mvc:annotation-driven>

    <!--3) ViewResolver -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <!-- viewClass需要在pom中引入两个包：standard.jar and jstl.jar -->
        <property name="viewClass"
                  value="org.springframework.web.servlet.view.JstlView"></property>
        <property name="prefix" value="/"/>
        <property name="suffix" value=".jsp"/>
    </bean>

    <!--4) 单独处理图片、样式、js等资源 -->
    <!--<mvc:resources location="/css/" mapping="/css/**"/>-->
<!--    <mvc:resources location="/images/" mapping="/images/**"/>-->
    <!--<mvc:resources location="/js/" mapping="/js/**"/>-->


</beans>

    3 修改web.xml

    <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">
  <display-name>Archetype Created Web Application</display-name>
  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath:applicationContext.xml</param-value>
  </context-param>
  <!-- 读取Spring上下文的监听器 -->
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>
  <!-- Spring和web项目集成end -->

  <!-- 防止Spring内存溢出监听器 -->
  <listener>
    <listener-class>org.springframework.web.util.IntrospectorCleanupListener</listener-class>
  </listener>

  <!-- 中文乱码处理 -->
  <filter>
    <filter-name>encodingFilter</filter-name>
    <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
    <!--web.xml 3.0的新特性，是否支持异步-->
    <async-supported>true</async-supported>
    <init-param>
      <param-name>encoding</param-name>
      <param-value>UTF-8</param-value>
    </init-param>
  </filter>
  <filter-mapping>
    <filter-name>encodingFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>

  <!-- Spring MVC servlet -->
  <servlet>
    <servlet-name>SpringMVC</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <!--此参数可以不配置，默认值为：/WEB-INF/springmvc-servlet.xml-->
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>/WEB-INF/springmvc-servlet.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
    <!--web.xml 3.0的新特性，是否支持异步-->
    <async-supported>true</async-supported>
  </servlet>
  <servlet-mapping>
    <servlet-name>SpringMVC</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>
</web-app>

    六、SpringMVC五种结果集处理

    HelloController：
    package com.psy.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

import javax.servlet.http.HttpServletRequest;

/**
 *  关于结果集处理分五种情况
 *  1、转发到页面(webapp下)
 *  2、转发到action请求
 *  3、重定向页面（webapp下）
 *  4、重定向到action
 *  5、转发到web-inf下的页面
 */
@Controller
public class HelloController {

    @RequestMapping("hello")
    public String hello(HttpServletRequest request){
        request.setAttribute("msg","转发到页面的方式");
        return "hello";
    }

    /**
     * 重定向到action中
     * @param request
     * @return
     */
    @RequestMapping("hello2")
    public String redirectPage(HttpServletRequest request){
        request.setAttribute("msg","重定向到action的方式");
        return "redirect:hello";
    }

    /**
     * 重定向到页面
     * @param request
     * @return
     */
    @RequestMapping("hello3")
    public String redirectPage2(HttpServletRequest request){
        Object msg = request.getAttribute("msg");
        return "redirect:/hello.jsp";
    }

    @RequestMapping("hello4")
    public String forwardAction(HttpServletRequest request){
        request.setAttribute("msg","重定向到action的方式");
        return "forward:hello3";
    }

    @RequestMapping("hello5")
    public String forwardAction2(HttpServletRequest request){
        request.setAttribute("msg","转发访问安全页面");
        return "en";
    }


}

    使用第五种转发到web-inf下的页面要注意更改springmvc-servlet.xml下的

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

    七、springMVC增删改查

    BookController：
    package com.psy.controller;

import com.psy.model.Book;
import com.psy.service.Bookservice;
import com.psy.util.PageBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;

import javax.servlet.http.HttpServletRequest;
import java.util.List;
import java.util.Map;

@Controller
@RequestMapping("/book")
public class BookController {
    @Autowired
    private Bookservice bookService;

    @RequestMapping("/list")
    public String list(Book book, HttpServletRequest request){
        PageBean pageBean = new PageBean();
        pageBean.setRequest(request);
        List<Map> list = this.bookService.listPager(book, pageBean);
        request.setAttribute("bookList",list);
        request.setAttribute("pageBean",pageBean);
        return  "bookList";
    }
    @RequestMapping("/preSave")
    public String preSave(Book book, HttpServletRequest request){
        if(book.getBid()!=null){
            Book b = this.bookService.selectByPrimaryKey(book.getBid());
            request.setAttribute("b",b);
        }
        return  "bookEdit";
    }

    @RequestMapping("/add")
    public String add(Book book, HttpServletRequest request){
        this.bookService.insert(book);
        return  "redirect:/book/list";
    }

    @RequestMapping("/del/{bid}")
    public String del(@PathVariable(value = "bid") Integer bid, HttpServletRequest request){
        this.bookService.deleteByPrimaryKey(bid);
        return  "redirect:/book/list";
    }

    @RequestMapping("/edit")
    public String edit(Book book, HttpServletRequest request){
        this.bookService.updateByPrimaryKey(book);
        return  "redirect:/book/list";
    }
}

     bookList.jsp:

    <%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
    <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
     <%@ taglib uri="/zking" prefix="z" %>
<!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>
<script type="text/javascript">
    function add(){
        // window.location.href = "bookEdit.jsp";
        window.location.href="${pageContext.request.contextPath}/book/preSave";
    }
    
    function update(bid){
        window.location.href = "${pageContext.request.contextPath}/book/preSave?bid="+bid;
    }
    
    function del(bid){
        window.location.href = "${pageContext.request.contextPath}/book/del/"+bid;
    }
</script>
</head>
<body>
    <form action="${pageContext.request.contextPath}/bookAction.action?methodName=list"
        method="post">
        书名：<input type="text" name="bname"> <input type="submit"
            value="确定">
    </form>
    <button onclick="add();">新增</button>
    <table border="1" width="100%">
        <tr>
            <td>编号</td>
            <td>名称</td>
            <td>价格</td>
            <td>操作</td>
        </tr>
        <c:forEach items="${bookList }" var="b">
            <tr>
                <td>${b.bid }</td>
                <td>${b.bname }</td>
                <td>${b.price }</td>
                <td>
                    <button onclick="update(${b.bid });">修改</button>&nbsp;&nbsp;&nbsp;
                    <button onclick="del(${b.bid });">删除</button>
                </td>
            </tr>
        </c:forEach>
    </table>
    <z:page pageBean="${pageBean }"></z:page>
</body>
</html>

    bookEdit.jsp:

    <%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!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>
<script type="text/javascript">
    function doSubmit(bid){
        var bookForm = document.getElementById("bookForm");
        if(bid){
            //修改时候执行
            bookForm.action = '${pageContext.request.contextPath}/book/edit';
        }else{
            //新增时候执行
            bookForm.action = '${pageContext.request.contextPath}/book/add';
        }
        bookForm.submit();
    }
</script>
</head>
<body>
    <form id="bookForm" action="" method="post">
        bid:<input type="text" name="bid" value="${b.bid }"><br>
        bname:<input type="text" name="bname" value="${b.bname }"><br>
        price:<input type="text" name="price" value="${b.price }"><br>
        <input type="submit" value="提交" onclick="doSubmit('${b.bid }');"><br>
    </form>
</body>
</html>

    PageTag:
    package com.psy.util;


import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.BodyTagSupport;
import java.io.IOException;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;


public class PageTag extends BodyTagSupport {

    private static final long serialVersionUID = 1L;
    private PageBean pageBean;
    public PageBean getPageBean() {
        return pageBean;
    }
    public void setPageBean(PageBean pageBean) {
        this.pageBean = pageBean;
    }
    @Override
    public int doStartTag() throws JspException {
        JspWriter out = pageContext.getOut();
        try {
            out.print(toHTML());
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return super.doStartTag();
    }
    private String toHTML() {
        StringBuffer sb = new StringBuffer();
        /*
         * 拼接向后台提交数据的form表单
         *     注意：拼接的form表单中的page参数是变化的，所以不需要保留上一次请求的值
         */
        sb.append("<form id='pageBeanForm' action='"+pageBean.getUrl()+"' method='post'>");
        sb.append("<input type='hidden' name='page'>");
        Map<String, String[]> parameterMap = pageBean.getMap();
        if(parameterMap != null && parameterMap.size() > 0) {
            Set<Entry<String, String[]>> entrySet = parameterMap.entrySet();
            for (Entry<String, String[]> entry : entrySet) {
                if(!"page".equals(entry.getKey())) {
                    String[] values = entry.getValue();
                    for (String val : values) {
                        sb.append("<input type='hidden' name='"+entry.getKey()+"' value='"+val+"'>");
                    }
                }
            }
        }
        sb.append("</form>");
        
        /*
         * 展示的分页条
         */
        sb.append("<div style='text-align: right; font-size: 12px;'>");
        sb.append("每页"+pageBean.getRows()+"条，共"+pageBean.getTotal()+"条，第"+pageBean.getPage()+"页，共"+pageBean.getMaxPage()+"页&nbsp;&nbsp;<a href='javascript:gotoPage(1)'>首页</a>&nbsp;&nbsp;<a");
        sb.append(" href='javascript:gotoPage("+pageBean.getPreivousPage()+")'>上一页</a>&nbsp;&nbsp;<a");
        sb.append(" href='javascript:gotoPage("+pageBean.getNextPage()+")'>下一页</a>&nbsp;&nbsp;<a");
        sb.append(" href='javascript:gotoPage("+pageBean.getMaxPage()+")'>尾页</a>&nbsp;&nbsp;<input type='text'");
        sb.append(" id='skipPage'");
        sb.append(" style='text-align: center; font-size: 12px;  50px;'>&nbsp;&nbsp;<a");
        sb.append(" href='javascript:skipPage()'>Go</a>");
        sb.append("</div>");
        
        /*
         * 给分页条添加与后台交互的js代码
         */
        sb.append("<script type='text/javascript'>");
        sb.append("        function gotoPage(page) {");
        sb.append("            document.getElementById('pageBeanForm').page.value = page;");
        sb.append("            document.getElementById('pageBeanForm').submit();");
        sb.append("        }");
        sb.append("        function skipPage() {");
        sb.append("            var page = document.getElementById('skipPage').value;");
        sb.append("            if(!page || isNaN(page) || parseInt(page)<1 || parseInt(page)>"+pageBean.getMaxPage()+"){");
        sb.append("                alert('请输入1~N的数字');");
        sb.append("                return;");
        sb.append("            }");
        sb.append("            gotoPage(page);");
        sb.append("        }");
        sb.append("</script>");
        return sb.toString();
    }
}

    八、springMVC静态资源处理

    如何访问静态资源

    在Springmvc-servlet.xml中添加：

      <!--4) 单独处理图片、样式、js等资源 -->
    <!--<mvc:resources location="/css/" mapping="/css/**"/>-->
    <mvc:resources location="/static/" mapping="/static/**"/>
    <!--<mvc:resources location="/js/" mapping="/js/**"/>-->
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  • 原文地址：https://www.cnblogs.com/psyu/p/11604645.html
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