springmvc入门

Springmvc之helloword实现

如何在项目中添加springmvc
1 添加相关依赖

<dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>${spring.version}</version>
      </dependency>

JSTL依赖
缺少下面的这两个jar包会报java.lang.NoClassDefFoundError: javax/servlet/jsp/jstl/core/Config
原因：org.springframework.web.servlet.view.JstlView在视图解析时需要这二个jar包

<jstl.version>1.2</jstl.version>
		<standard.version>1.1.2</standard.version>
		<tomcat-jsp-api.version>8.0.47</tomcat-jsp-api.version>

<!-- 5.3、jstl、standard -->
        <dependency>
            <groupId>jstl</groupId>
            <artifactId>jstl</artifactId>
            <version>${jstl.version}</version>
        </dependency>
        <dependency>
            <groupId>taglibs</groupId>
            <artifactId>standard</artifactId>
            <version>${standard.version}</version>
        </dependency>

        <!-- 5.4、tomcat-jsp-api -->
        <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.cbw.ssm"/>

    <!--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 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>


  <filter>
    <filter-name>encodingFilter</filter-name>
    <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
    <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>
</web-app>

测试

package com.cbw.ssm.controller;

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

/**
 * @author 陈公子
 * @site www.cbowen.com
 * @company cbw公司
 * @create 2019-11-23 14:51
 */
@Controller
public class HelloController {
    @RequestMapping("/say1")
    public String say(){
        return "hello";
    }
}

hello.jsp

<%--
  Created by IntelliJ IDEA.
  User: 125x
  Date: 2019/11/24
  Time: 20:07
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
springMvc 陈公子
</body>
</html>

Springmvc简介及配置
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。
springmvc框架的运作原理

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
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
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)
再现 5 ModelAndView的逻辑视图名–>ViewRecolver

 @RequestMapping("say2")
    public ModelAndView say2(){
    ModelAndView mv=new ModelAndView();
    mv.setViewName("hello2");
   mv.addObject("msg","我是你爸爸真可爱，养你这么大");
        return mv;
    }

效果：

Springmvc常用注解及返回值处理

增删改查
tag

package com.cbw.ssm.tag;

import com.cbw.ssm.utils.PageBean;

import java.io.IOException;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.BodyTagSupport;


public class PageTag extends BodyTagSupport {

    private static final long serialVersionUID = 383258790166308355L;

    private PageBean pageBean;

    public int doStartTag() throws JspException {
        JspWriter out = pageContext.getOut();
        try {
            out.print(toHTML());
        } catch (IOException e) {
            e.printStackTrace();
        }
        return SKIP_BODY;
    }

    private String toHTML() {
        StringBuilder sb = new StringBuilder();
//     拼接下一次分页请求搜提交的分页表单
        sb.append("<form id='pageBeanForm' action='"+pageBean.getUrl()+"' method='post'>");
        sb.append("<input type='hidden' name='page'> ");
        Map<String, String[]> paMap = pageBean.getMap();
        if(paMap != null && paMap.size()>0) {
            Set<Entry<String, String[]>> entrySet = paMap.entrySet();

            for (Entry<String, String[]> entry : entrySet) {
                for(String value :entry.getValue() ) {
                    if(!"page".equals(entry.getKey())) {
                        sb.append("<input type='hidden' name='"+entry.getKey()+"' value='"+value+"'>");
                    }
                }
            }
        }
        sb.append("</form>");
//     拼接分页条
        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;");
        sb.append(" <a href='javascript:gotoPage(1)'>首页</a>&nbsp;&nbsp;");
        sb.append(" <a href='javascript:gotoPage("+pageBean.getPreivousPage()+")'>上一页</a>&nbsp;&nbsp;");
        sb.append(" <a href='javascript:gotoPage("+pageBean.getNextPage()+")'>下一页</a>&nbsp;&nbsp;");
        sb.append(" <a href='javascript:gotoPage("+pageBean.getMaxPage()+")'>尾页</a>&nbsp;&nbsp;");
        sb.append(" <input type='text' id='skipPage' style='text-align: center; font-size: 12px; width: 50px;'>&nbsp;&nbsp;");
        sb.append(" <a href='javascript:skipPage()'>Go</a>");
        sb.append(" </div>");
//     拼接分页的javascript 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();
    }

    public PageBean getPageBean() {
        return pageBean;
    }

    public void setPageBean(PageBean pageBean) {
        this.pageBean = pageBean;
    }

}

BookServiceImpl

package com.cbw.ssm.service.impl;

import com.cbw.ssm.mapper.BookMapper;
import com.cbw.ssm.model.Book;
import com.cbw.ssm.service.BookService;
import com.cbw.ssm.utils.PageBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * @author cbw
 * @site www.cbw.com
 * @company xxx公司
 * @create 2019-11-17 19:26
 */
@Service
public class BookServiceImpl implements BookService {
    @Autowired
    private BookMapper bookMapper;

    @Override
    public int insert(Book record) {
        return bookMapper.insert(record);
    }

    @Override
    public int insertSelective(Book record) {
        return bookMapper.insertSelective(record);
    }

    @Override
    public int updateByPrimaryKeySelective(Book record) {
        return bookMapper.updateByPrimaryKeySelective(record);
    }

    @Override
    public int updateByPrimaryKey(Book record) {
        return bookMapper.updateByPrimaryKey(record);
    }


    @Override
    public int deleteByPrimaryKey(Integer bid) {
        return bookMapper.deleteByPrimaryKey(bid);
    }

    @Override
    public Book selectByPrimaryKey(Integer bid) {
        return bookMapper.selectByPrimaryKey(bid);
    }

    @Override
    public List<Map> listPager(Map map, PageBean pageBean) {
        return bookMapper.listPager(map);
    }

    @Override
    public List<Map> listPager(Book book, PageBean pageBean) {
        Map map=new HashMap();
        map.put("bname",book.getBname());
        return bookMapper.listPager(map);
    }
}

BookController

package com.cbw.ssm.controller;

import com.cbw.ssm.model.Book;
import com.cbw.ssm.service.BookService;
import com.cbw.ssm.utils.PageBean;
import org.apache.ibatis.annotations.Param;
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;

/**
 * @author 陈公子
 * @site www.cbowen.com
 * @company zk公司
 * @create  2019-11-25 9:45
 */
@Controller
@RequestMapping("/book")
public class BookController {
    @Autowired
    private BookService bookService;
    @RequestMapping("/list")
    public String list(Book book, HttpServletRequest req){
        PageBean pageBean=new PageBean();
        pageBean.setRequest(req);
         List<Map> list = bookService.listPager(book, pageBean);
         req.setAttribute("bookList",list);
         req.setAttribute("pageBean",pageBean);
        return  "bookList";
    }
    @RequestMapping("/add")
    public String add(Book book){
        bookService.insert(book);
        return  "redirect:/book/list";
    }
    @RequestMapping("/del/{bid}")
    public String del(@PathVariable("bid") Integer bid){
        bookService.deleteByPrimaryKey(bid);
        return  "redirect:/book/list";
    }
    @RequestMapping("/edit")
    public String edit(Book book){
        bookService.updateByPrimaryKey(book);
        return  "redirect:/book/list";
    }

    /**
     * 跳转
     * @return
     */
    @RequestMapping("/preSave")
    public String preSave(Book book,HttpServletRequest req){
        if(book ==null || book.getBid() ==null || book.getBid()==0){
return  "bookEdit";
        }
        Map map= bookService.listPager(book,null).get(0);
        req.setAttribute("b",map);
        return   "bookEdit";
    }
}

jsp页面：
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="/cbw"  prefix="b"%>
<!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>书籍主页</title>
</head>
<body>
<h2>小说目录</h2>
	<br>
	<form action="${pageContext.request.contextPath}/book/list" method="post">
		<!--用户设置查询 一页20条记录  -->
	 <!-- 	<input type="hidden" name="rows" value="20"/> -->
		<!--用户设置不分页  -->
	 	<!-- <input type="hidden" name="pagination" value="false"/> -->
		书名：<input type="text" name="bname"> <input type="submit"
			value="确定">
	</form>
	<a href="${pageContext.request.contextPath}/book/preSave">增加</a>
	<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>
				  <a href="${pageContext.request.contextPath}/book/preSave?bid=${b.bid }">修改</a>
				  <a href="${pageContext.request.contextPath}/book/del/${b.bid}">删除</a>
				</td>
			</tr> 
		</c:forEach> 
	</table>
	<b:page pageBean="${pageBean}"></b: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>编辑页面</title>
</head>
<body>
<form action="${pageContext.request.contextPath}${b.bname == null ?'/book/add' : '/book/edit'}" method="post">
 bid:  <input type="text" value="${b.bid}" name="bid"/><br>
 bname:<input type="text" value="${b.bname}" name="bname"/><br>
 price:<input type="text" value="${b.price}" name="price"/><br>
 <button type="submit">确认</button>
</form>
</body>
</html>

查

增加


改


删