SpringMvc入门

Springmvc简介及配置

1. 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。

2. SpringMVC处理请求的流程

2.1 首先用户发送请求-->DispatherServlet

2.2 DispatcherServlet-->HandlerMapping

2.3 DispatcherServlet-->HandlerAdapter

2.4 HandlerAdapter-->处理器功能处理方法的调用

2.5 ModelAndView的逻辑视图名-->ViewRecolver

2.6 View-->渲染

2.7 返回控制权给DispatcherServlet，由DispatcherServlet返回呼应给用户，流程结束

3. SpringMVC核心开发步骤

3.1 DispatcherServlet在web.xml中的部署描述，从而拦截请求到springMVC

3.2 HandlerMapping的配置，从而将请求映射到处理器

3.3 HandlerAdapter的配置，从而支持多种类型的处理器

3.4 处理器(页面控制器)的配置，从而刊行功能处理

3.5 ViewResolver的配置，从而将逻辑视图名解析为具体的视图技术

4. SpringMVC的组件

4.1 前端控制器(DispatcherServlet)

4.2 请求到处理器映射(HandlerMapping)

4.3 处理器适配器(HandlerAdapter)

4.4 视图解析器(ViewResolver)

4.5 处理器或页面控制器(Controller)

4.6 验证器(Validator)

4.6 命令对象(Command 请求参数绑定到的对象就叫命令对象)

4.7 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)

5. 如何在项目中添加springmvc

5.1 添加相关依赖

1  <dependency>
2         <groupId>org.springframework</groupId>
3         <artifactId>spring-webmvc</artifactId>
4         <version>${spring.version}</version>
5       </dependency>

 1 <dependency>
 2           <groupId>jstl</groupId>
 3           <artifactId>jstl</artifactId>
 4           <version>1.2</version>
 5       </dependency>
 6       <dependency>
 7           <groupId>taglibs</groupId>
 8           <artifactId>standard</artifactId>
 9           <version>1.1.2</version>
10       </dependency>

修改Web.xml

 1 <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
 2          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 3          xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
 4          version="3.1">
 5   <display-name>Archetype Created Web Application</display-name>
 6 
 7   <welcome-file-list>
 8     <welcome-file>login.jsp</welcome-file>
 9   </welcome-file-list>
10 
11   <context-param>
12     <param-name>contextConfigLocation</param-name>
13     <param-value>classpath:applicationContext.xml</param-value>
14   </context-param>
15   <!-- 读取Spring上下文的监听器 -->
16   <listener>
17     <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
18   </listener>
19   <!-- Spring和web项目集成end -->
20 
21   <!-- 防止Spring内存溢出监听器 -->
22   <listener>
23     <listener-class>org.springframework.web.util.IntrospectorCleanupListener</listener-class>
24   </listener>
25 
26     <!-- 中文乱码处理 -->
27   <filter>
28     <filter-name>encodingFilter</filter-name>
29     <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
30     <!--web.xml 3.0的新特性，是否支持异步-->
31     <async-supported>true</async-supported>
32     <init-param>
33       <param-name>encoding</param-name>
34       <param-value>UTF-8</param-value>
35     </init-param>
36   </filter>
37   <filter-mapping>
38     <filter-name>encodingFilter</filter-name>
39     <url-pattern>/*</url-pattern>
40   </filter-mapping>
41 
42   <!-- Spring MVC servlet -->
43   <servlet>
44     <servlet-name>SpringMVC</servlet-name>
45     <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
46     <!--此参数可以不配置，默认值为：/WEB-INF/springmvc-servlet.xml-->
47     <init-param>
48       <param-name>contextConfigLocation</param-name>
49       <param-value>/WEB-INF/springmvc-servlet.xml</param-value>
50     </init-param>
51     <load-on-startup>1</load-on-startup>
52     <!--web.xml 3.0的新特性，是否支持异步-->
53     <async-supported>true</async-supported>
54   </servlet>
55   <servlet-mapping>
56     <servlet-name>SpringMVC</servlet-name>
57     <url-pattern>/</url-pattern>
58   </servlet-mapping>
59 
60 </web-app>

添加springmvc-servlet.xml（在WEB-INF下）

 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" xmlns:aop="http://www.springframework.org/schema/aop"
 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-4.3.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">
 8     <!-- 通过context:component-scan元素扫描指定包下的控制器-->
 9     <!--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)-->
10     <aop:aspectj-autoproxy/>
11     <context:component-scan base-package="com.Mybatis"/>
12 
13     <!--2) 此标签默认注册DefaultAnnotationHandlerMapping和AnnotationMethodHandlerAdapter -->
14     <!--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，-->
15     <!--@NumberFormatannotation支持，@DateTimeFormat支持，@Valid支持，读写XML的支持（JAXB），读写JSON的支持（Jackson）-->
16     <mvc:annotation-driven></mvc:annotation-driven>
17 
18     <!--3) ViewResolver -->
19     <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
20         <!-- viewClass需要在pom中引入两个包：standard.jar and jstl.jar -->
21         <property name="viewClass"
22                   value="org.springframework.web.servlet.view.JstlView"></property>
23         <property name="prefix" value="/WEB-INF/"/>
24         <property name="suffix" value=".jsp"/>
25     </bean>
26 
27     <!--4) 单独处理图片、样式、js等资源 -->
28     <!--<mvc:resources location="/css/" mapping="/css/**"/>-->
29     <!--<mvc:resources location="/images/" mapping="/images/**"/>-->
30     <!--<mvc:resources location="/js/" mapping="/js/**"/>-->
31 
32     <mvc:resources location="/static/" mapping="/static/**"/>
33 
34 </beans>

Springmvc之helloword实现

 1 package com.Mybatis.controller;
 2 
 3 import org.springframework.stereotype.Controller;
 4 import org.springframework.web.bind.annotation.RequestMapping;
 5 import org.springframework.web.bind.annotation.ResponseBody;
 6 
 7 import java.util.HashMap;
 8 import java.util.Map;
 9 
10 
11 /**
12  * 5种情况
13  * 1、转发到页面
14  * 2、转发到根路径下的页面
15  * 3、转发到requestMapping
16  * 4、重定向到根路径下的页面
17  * 5、重定向到requestMapping下
18  */
19 
20 @Controller
21 public class HelloController {
22 
23     @ResponseBody
24     @RequestMapping("/hello1")
25     public String hello1(){
26         System.out.println("holle springmvc  你大爷");
27         return  "holle springmvc  你大爷";
28     }
29 
30     @ResponseBody
31     @RequestMapping("/hello2")
32     public String hello2(){
33         System.out.println("holle springmvc  你二大爷");
34         return "hello";
35     }
36 
37     @ResponseBody
38     @RequestMapping("/hello3")
39     public Map hello3(){
40         System.out.println("holle springmvc  你二大爷");
41         Map map = new HashMap();
42         map.put("total",12);
43         map.put("rows","一串数据");
44         return  map;
45     }
46 
47 //    转发到页面
48 
49 @RequestMapping("/forward1")
50     public String forward1(){
51         System.out.println("进了forward");
52         return "aaa";
53     }
54 
55 //    转发到根路径下的页面
56 @RequestMapping("/forward2")
57     public String forward2(){
58         return "forward:/bbb.jsp";
59     }
60 
61 //    转发到requestMapping
62 @RequestMapping("/forward3")
63     public String forward3(){
64         return "forward:/forward1";
65     }
66 
67 //    重定向到根路径下的页面
68 @RequestMapping("/redirect1")
69     public String redirect1(){
70         return "redirect:/bbb.jsp";
71     }
72 
73 //    重定向到requestMapping下
74 @RequestMapping("/redirect2")
75     public String redirect2(){
76         return "forward:/forward1";
77     }
78 
79 }

Springmvc常用注解及返回值处理

通过CRUD案例来说明

Controller

Requestmapping

Requestparam

传参

自定义标签和分页

BookController

 1 package com.Mybatis.controller;
 2 
 3 import com.Mybatis.model.Book;
 4 import com.Mybatis.service.BookService;
 5 import com.Mybatis.util.PageBean;
 6 import org.springframework.beans.factory.annotation.Autowired;
 7 import org.springframework.stereotype.Controller;
 8 import org.springframework.web.bind.annotation.PathVariable;
 9 import org.springframework.web.bind.annotation.RequestMapping;
10 
11 import javax.servlet.http.HttpServletRequest;
12 import java.util.List;
13 
14 @Controller
15 @RequestMapping("/book")
16 public class BookController {
17     @Autowired
18     private BookService bookService;
19 
20 
21     @RequestMapping("/list")
22     public String list(Book book,HttpServletRequest req){
23         PageBean pageBean = new PageBean();
24         pageBean.setRequest(req);
25         List<Book> books = this.bookService.listPager1(book, pageBean);
26         req.setAttribute("bookList",books);
27         req.setAttribute("pageBean",pageBean);
28         return "bookList";
29     }
30 
31     @RequestMapping("/preSave")
32     public String preSave(Book  book, HttpServletRequest req){
33         if(book != null && book.getBid() != null && book.getBid() != 0){
34             Book b = this.bookService.selectByPrimaryKey(book.getBid());
35             req.setAttribute("book2",b);
36         }
37         return "bookEdit";
38     }
39 
40     @RequestMapping("/add")
41     public String add(Book book, HttpServletRequest req){
42         this.bookService.insertSelective(book);
43         return "redirect:/book/list";
44     }
45 
46     @RequestMapping("/edit")
47     public String edit(Book book, HttpServletRequest req){
48         this.bookService.updateByPrimaryKeySelective(book);
49         return "redirect:/book/list";
50     }
51 
52     @RequestMapping("/del/{bid}")
53     public String del(@PathVariable("bid") Integer bid, HttpServletRequest req){
54         this.bookService.deleteByPrimaryKey(bid);
55         return "redirect:/book/list";
56     }
57 
58 
59 }

分页工具类

PageBean

  1 package com.Mybatis.util;
  2 
  3 import javax.servlet.http.HttpServletRequest;
  4 import java.io.Serializable;
  5 import java.util.Map;
  6 
  7 public class PageBean implements Serializable {
  8 
  9     private static final long serialVersionUID = 2422581023658455731L;
 10 
 11     //页码
 12     private int page=1;
 13     //每页显示记录数
 14     private int rows=10;
 15     //总记录数
 16     private int total=0;
 17     //是否分页
 18     private boolean isPagination=true;
 19     //上一次的请求路径
 20     private String url;
 21     //获取所有的请求参数
 22     private Map<String,String[]> map;
 23     
 24     public PageBean() {
 25         super();
 26     }
 27     
 28     //设置请求参数
 29     public void setRequest(HttpServletRequest req) {
 30         String page=req.getParameter("page");
 31         String rows=req.getParameter("rows");
 32         String pagination=req.getParameter("pagination");
 33         this.setPage(page);
 34         this.setRows(rows);
 35         this.setPagination(pagination);
 36         this.url=req.getContextPath()+req.getServletPath();
 37         this.map=req.getParameterMap();
 38     }
 39     public String getUrl() {
 40         return url;
 41     }
 42 
 43     public void setUrl(String url) {
 44         this.url = url;
 45     }
 46 
 47     public Map<String, String[]> getMap() {
 48         return map;
 49     }
 50 
 51     public void setMap(Map<String, String[]> map) {
 52         this.map = map;
 53     }
 54 
 55     public int getPage() {
 56         return page;
 57     }
 58 
 59     public void setPage(int page) {
 60         this.page = page;
 61     }
 62     
 63     public void setPage(String page) {
 64         if(null!=page&&!"".equals(page.trim()))
 65             this.page = Integer.parseInt(page);
 66     }
 67 
 68     public int getRows() {
 69         return rows;
 70     }
 71 
 72     public void setRows(int rows) {
 73         this.rows = rows;
 74     }
 75     
 76     public void setRows(String rows) {
 77         if(null!=rows&&!"".equals(rows.trim()))
 78             this.rows = Integer.parseInt(rows);
 79     }
 80 
 81     public int getTotal() {
 82         return total;
 83     }
 84 
 85     public void setTotal(int total) {
 86         this.total = total;
 87     }
 88     
 89     public void setTotal(String total) {
 90         this.total = Integer.parseInt(total);
 91     }
 92 
 93     public boolean isPagination() {
 94         return isPagination;
 95     }
 96     
 97     public void setPagination(boolean isPagination) {
 98         this.isPagination = isPagination;
 99     }
100     
101     public void setPagination(String isPagination) {
102         if(null!=isPagination&&!"".equals(isPagination.trim()))
103             this.isPagination = Boolean.parseBoolean(isPagination);
104     }
105     
106     /**
107      * 获取分页起始标记位置
108      * @return
109      */
110     public int getStartIndex() {
111         //(当前页码-1)*显示记录数
112         return (this.getPage()-1)*this.rows;
113     }
114     
115     /**
116      * 末页
117      * @return
118      */
119     public int getMaxPage() {
120         int totalpage=this.total/this.rows;
121         if(this.total%this.rows!=0)
122             totalpage++;
123         return totalpage;
124     }
125     
126     /**
127      * 下一页
128      * @return
129      */
130     public int getNextPage() {
131         int nextPage=this.page+1;
132         if(this.page>=this.getMaxPage())
133             nextPage=this.getMaxPage();
134         return nextPage;
135     }
136     
137     /**
138      * 上一页
139      * @return
140      */
141     public int getPreivousPage() {
142         int previousPage=this.page-1;
143         if(previousPage<1)
144             previousPage=1;
145         return previousPage;
146     }
147 
148     @Override
149     public String toString() {
150         return "PageBean [page=" + page + ", rows=" + rows + ", total=" + total + ", isPagination=" + isPagination
151                 + "]";
152     }
153 }

Tag类

PageTag

 1 package com.Mybatis.tag;
 2 
 3 import com.Mybatis.util.PageBean;
 4 
 5 import javax.servlet.jsp.JspException;
 6 import javax.servlet.jsp.JspWriter;
 7 import javax.servlet.jsp.tagext.BodyTagSupport;
 8 import java.io.IOException;
 9 import java.util.Map;
10 import java.util.Map.Entry;
11 import java.util.Set;
12 
13 
14 public class PageTag extends BodyTagSupport {
15 
16     private static final long serialVersionUID = 1L;
17     private PageBean pageBean;
18     public PageBean getPageBean() {
19         return pageBean;
20     }
21     public void setPageBean(PageBean pageBean) {
22         this.pageBean = pageBean;
23     }
24     @Override
25     public int doStartTag() throws JspException {
26         JspWriter out = pageContext.getOut();
27         try {
28             out.print(toHTML());
29         } catch (IOException e) {
30             // TODO Auto-generated catch block
31             e.printStackTrace();
32         }
33         return super.doStartTag();
34     }
35     private String toHTML() {
36         StringBuffer sb = new StringBuffer();
37         /*
38          * 拼接向后台提交数据的form表单
39          *     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
40          */
41         sb.append("<form id='pageBeanForm' action='"+pageBean.getUrl()+"' method='post'>");
42         sb.append("<input type='hidden' name='page'>");
43         Map<String, String[]> parameterMap = pageBean.getMap();
44         if(parameterMap != null && parameterMap.size() > 0) {
45             Set<Entry<String, String[]>> entrySet = parameterMap.entrySet();
46             for (Entry<String, String[]> entry : entrySet) {
47                 if(!"page".equals(entry.getKey())) {
48                     String[] values = entry.getValue();
49                     for (String val : values) {
50                         sb.append("<input type='hidden' name='"+entry.getKey()+"' value='"+val+"'>");
51                     }
52                 }
53             }
54         }
55         sb.append("</form>");
56         
57         /*
58          * 展示的分页条
59          */
60         sb.append("<div style='text-align: right; font-size: 12px;'>");
61         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");
62         sb.append(" href='javascript:gotoPage("+pageBean.getPreivousPage()+")'>上一页</a>&nbsp;&nbsp;<a");
63         sb.append(" href='javascript:gotoPage("+pageBean.getNextPage()+")'>下一页</a>&nbsp;&nbsp;<a");
64         sb.append(" href='javascript:gotoPage("+pageBean.getMaxPage()+")'>尾页</a>&nbsp;&nbsp;<input type='text'");
65         sb.append(" id='skipPage'");
66         sb.append(" style='text-align: center; font-size: 12px;  50px;'>&nbsp;&nbsp;<a");
67         sb.append(" href='javascript:skipPage()'>Go</a>");
68         sb.append("</div>");
69         
70         /*
71          * 给分页条添加与后台交互的js代码
72          */
73         sb.append("<script type='text/javascript'>");
74         sb.append("        function gotoPage(page) {");
75         sb.append("            document.getElementById('pageBeanForm').page.value = page;");
76         sb.append("            document.getElementById('pageBeanForm').submit();");
77         sb.append("        }");
78         sb.append("        function skipPage() {");
79         sb.append("            var page = document.getElementById('skipPage').value;");
80         sb.append("            if(!page || isNaN(page) || parseInt(page)<1 || parseInt(page)>"+pageBean.getMaxPage()+"){");
81         sb.append("                alert('请输入1~N的数字');");
82         sb.append("                return;");
83         sb.append("            }");
84         sb.append("            gotoPage(page);");
85         sb.append("        }");
86         sb.append("</script>");
87         return sb.toString();
88     }
89 }

返回值处理

HelloController

 1 package com.Mybatis.controller;
 2 
 3 import org.springframework.stereotype.Controller;
 4 import org.springframework.web.bind.annotation.RequestMapping;
 5 import org.springframework.web.bind.annotation.ResponseBody;
 6 
 7 import java.util.HashMap;
 8 import java.util.Map;
 9 
10 
11 /**
12  * 5种情况
13  * 1、转发到页面
14  * 2、转发到根路径下的页面
15  * 3、转发到requestMapping
16  * 4、重定向到根路径下的页面
17  * 5、重定向到requestMapping下
18  */
19 
20 @Controller
21 public class HelloController {
22 
23     @ResponseBody
24     @RequestMapping("/hello1")
25     public String hello1(){
26         System.out.println("holle springmvc  你大爷");
27         return  "holle springmvc  你大爷";
28     }
29 
30     @ResponseBody
31     @RequestMapping("/hello2")
32     public String hello2(){
33         System.out.println("holle springmvc  你二大爷");
34         return "hello";
35     }
36 
37     @ResponseBody
38     @RequestMapping("/hello3")
39     public Map hello3(){
40         System.out.println("holle springmvc  你二大爷");
41         Map map = new HashMap();
42         map.put("total",12);
43         map.put("rows","一串数据");
44         return  map;
45     }
46 
47 //    转发到页面
48 
49 @RequestMapping("/forward1")
50     public String forward1(){
51         System.out.println("进了forward");
52         return "aaa";
53     }
54 
55 //    转发到根路径下的页面
56 @RequestMapping("/forward2")
57     public String forward2(){
58         return "forward:/bbb.jsp";
59     }
60 
61 //    转发到requestMapping
62 @RequestMapping("/forward3")
63     public String forward3(){
64         return "forward:/forward1";
65     }
66 
67 //    重定向到根路径下的页面
68 @RequestMapping("/redirect1")
69     public String redirect1(){
70         return "redirect:/bbb.jsp";
71     }
72 
73 //    重定向到requestMapping下
74 @RequestMapping("/redirect2")
75     public String redirect2(){
76         return "forward:/forward1";
77     }
78 
79 }