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没有学过的同学,建议先学MyBatis,后学Spring,这次在此基础上我们来学习SpringMVC,此篇学完再无后端!
❤️爆肝六万字最全总结Java数据库编程MyBatis(建议收藏)
❤️爆肝万字!一文最全总结之Spring从入门到入土❤️(建议收藏)
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Spring web mvc是表现层的框架,它是Spring框架的一部分,我们可以从Spring的整体结构中看得出来:
l 1)核心控制器:处理特定请求。(例如:以*.action为后缀)
名称:DispatcherServlet
配置:是一个servlet,需要在web.xml中配置。
XML:需要确定核心XML配置文件的位置
l 2)核心XML配置文件:确定Controller位置、确定JSP页面位置
名称:springmvc.xml
l 3)控制器:开发人员编写的主要内容
名称:*Controller
l 流程示意图
在index.html中点击 Hello SpringMVC 超链接,在 show01 .jsp 页面显示信息。
整体思路:
跟HelloServlet入门案例几乎相同 .
服务器设置一个Controller,相当于之前的Servlet,可以接收请求,把请求在转发给jsp页面.
这里的区别就是需要设置web.xml和springmvc.xml两个配置文件,前者是用来配置核心控制器,后者是用来扫描我们自己书写的Controller的.
书写步骤:
1.拷贝pom文件,SpringMVC.xml文件和web.xml配置文件核心代码.
2.创建HelloController和show01.jsp
项目结构如下:
获取pom文件:
参见当前文档末尾的附录
获取springmvc.xml文件
代码如下直接拷贝
获取Web.xml代码配置如下:
Archetype Created Web Application
springmvc
org.springframework.web.servlet.DispatcherServlet
contextConfigLocation
classpath:springmvc.xml
springmvc
*.action
创建HelloController.java
package com.Maynor.controller;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
@Controller
public class HelloController {
@RequestMapping("/hello.action")
public String show(Model model){
model.addAttribute("data", "嘿嘿嘿");
return "/WEB-INF/show01.jsp";
}
}
Show01.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
Title
你好啊 老弟儿 ${data}
Index.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
Hello World!
入门案例
测试结果:
index.jsp页面
点击入门案例结果:
该需求跟上一个入门案例需求完全相同.
在index.html中点击 Hello SpringMVC 超链接,在 show01 .jsp 页面显示信息。
区别在于实现的时候:
使用 WebInitializer类代替web.xml
使用MVCConfig代替springmvc.xml
书写步骤:
1.拷贝pom文件,书写MVCConfig和WebInitializer类.
2.创建HelloController和show01.jsp
项目结构如下:
Pom文件,沿用上一个案例.即附录
MVCConfig类代码如下:
package com.Maynor.config;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
@Configuration
@ComponentScan("com.Maynor.controller")
public class MVCConfig {
}
传统Web项目中,程序的入口是web.xml文件。
在spring4中提供WebApplicationInitializer接口,表示服务器启动初始化。也就是说接口实现类中编写的内容,就是web.xml文件中配置的内容。
类或方法 | 描述 |
---|---|
AnnotationConfigWebApplicationContext | WEB环境下spring工厂 |
servletContext.addFilter(name , Class) | 添加过滤器,等效 |
servletContext.addServlet(name , Class) | 添加servlet,等效 |
过滤器相关方法 ServletRegistration.Dynamic | 描述 |
---|---|
addMapping(urlPatterns) | 追加过滤路径 |
setLoadOnStartup(int) | 设置启动顺序 |
WebInitializer类代码如下:
package com.Maynor.config;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.web.WebApplicationInitializer;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.servlet.DispatcherServlet;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRegistration;
public class WebInitializer implements WebApplicationInitializer {
@Override
public void onStartup(ServletContext servletContext) throws ServletException {
//1.初始化spring容器
AnnotationConfigWebApplicationContext applicationContext = new AnnotationConfigWebApplicationContext();
applicationContext.register(MVCConfig.class);
applicationContext.setServletContext(servletContext);
//2.设置核心控制器
ServletRegistration.Dynamic springMVCServlet = servletContext.addServlet("springmvc", new DispatcherServlet(applicationContext));
springMVCServlet.addMapping("*.action");
springMVCServlet.setLoadOnStartup(2);
}
}
HelloController代码:
package com.Maynor.controller;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
@Controller
public class HelloController {
@RequestMapping(path = "/hello.action")
public String show(Model model){
model.addAttribute("data", "呵呵呵");
return "/WEB-INF/show01.jsp";
}
}
Show01.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
Title
来了 老弟儿 ${data}
练习:
查询所有. 希望得到如下结果:
参考代码:
l 编写JavaBean用于封装数据
public class Item {
private String name; //名称
private Float price; //价格
private String detail; //详情
l 编写业务控制器Controller
@Controller
@RequestMapping("/user")
public class HelloController {
@RequestMapping("showInfo")
public String showInfo(Model model){
System.out.println("展示页面");
//1 模拟数据
List- list = new ArrayList
- ();
list.add(new Item("联想笔记本", 6999f, "ThinkPad T430 联想笔记本电脑!"));
list.add(new Item("苹果手机", 8800f, "iphone X 苹果手机!"));
//设置数据
model.addAttribute("list", list);
return "/showInfo.jsp";
}
}
l 展示数据
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%--
Created by IntelliJ IDEA.
User: 86153
Date: 2019/6/14
Time: 0:50
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
Title
名称
价格
描述
${item.name }
${item.price }
${item.detail }
配置类
*MVCConfig
@Configuration
@ComponentScan("com.Maynor.controller")
public class MVCConfiguration {
}
WebInitalizer
public class WebInitializer implements WebApplicationInitializer {
@Override
public void onStartup(ServletContext servletContext) throws ServletException {
//1 初始化spring容器
AnnotationConfigWebApplicationContext appliation = new AnnotationConfigWebApplicationContext();
appliation.register(MVCConfiguration.class);
appliation.setServletContext(servletContext);
//3 前端控制器
ServletRegistration.Dynamic springMvcServlet = servletContext.addServlet("springmvc", new DispatcherServlet(appliation));
springMvcServlet.addMapping("*.action");
springMvcServlet.setLoadOnStartup(2);
}
}
测试:
l 步骤2:启动,并访问
http://localhost:8080/s02/user/showInfo.action
需求:
改造ums 实现 查询所有用户.
示意图如下:
思路:
环境搭建:拷贝pom,资源文件和配置文件,初始化数据库和表,创建javaBean
编写功能:dao,Service,Controller
编写配置类:SpringConfig,MyBatisConfig,SpringMvcConfig,Web启动类.
测试
项目最终结构如下:
<org.springframework.version>4.2.4.RELEASEorg.springframework.version>
<dependencies>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-beansartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-coreartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-contextartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-expressionartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-context-supportartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-aopartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-aspectsartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-instrumentartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-messagingartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-jdbcartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-ormartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-oxmartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-jmsartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-txartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-websocketartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-webartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-webmvc-portletartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-webmvcartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-testartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>junitgroupId>
<artifactId>junitartifactId>
<version>4.12version>
<scope>testscope>
dependency>
<dependency>
<groupId>tk.mybatisgroupId>
<artifactId>mapperartifactId>
<version>3.5.2version>
dependency>
<dependency>
<groupId>com.github.pagehelpergroupId>
<artifactId>pagehelperartifactId>
<version>3.7.5version>
dependency>
<dependency>
<groupId>org.mybatisgroupId>
<artifactId>mybatisartifactId>
<version>3.4.5version>
dependency>
<dependency>
<groupId>mysqlgroupId>
<artifactId>mysql-connector-javaartifactId>
<version>5.1.47version>
dependency>
<dependency>
<groupId>org.mybatisgroupId>
<artifactId>mybatis-springartifactId>
<version>1.3.2version>
dependency>
<dependency>
<groupId>com.alibabagroupId>
<artifactId>druidartifactId>
<version>1.1.10version>
dependency>
<dependency>
<groupId>javax.servletgroupId>
<artifactId>javax.servlet-apiartifactId>
<version>3.1.0version>
<scope>providedscope>
dependency>
<dependency>
<groupId>jstlgroupId>
<artifactId>jstlartifactId>
<version>1.2version>
dependency>
<dependency>
<groupId>javax.servlet.jspgroupId>
<artifactId>jsp-apiartifactId>
<version>2.1version>
<scope>providedscope>
dependency>
dependencies>
<plugin>
<groupId>org.apache.maven.pluginsgroupId>
<artifactId>maven-compiler-pluginartifactId>
<version>3.2version>
<configuration>
<source>1.8source>
<target>1.8target>
<encoding>UTF-8encoding>
<showWarnings>trueshowWarnings>
configuration>
plugin>
<plugin>
<groupId>org.apache.tomcat.mavengroupId>
<artifactId>tomcat7-maven-pluginartifactId>
<version>2.1version>
<configuration>
<port>8081port>
<server>tomcat7server>
configuration>
plugin>
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://127.0.0.1:3306/ums_db
jdbc.username=root
jdbc.password=1234
CREATE TABLE t_user (
uid INT(11) PRIMARY KEY NOT NULL AUTO_INCREMENT,
login_name VARCHAR(50) DEFAULT NULL,
login_pwd VARCHAR(32) DEFAULT NULL,
age INT(11) DEFAULT NULL,
birthday DATE DEFAULT NULL,
sex VARCHAR(1) DEFAULT NULL,
education VARCHAR(50),
telephone VARCHAR(11),
interest VARCHAR(100),
remark VARCHAR(200)
)
insert into `t_user`(`uid`,`login_name`,`login_pwd`,`age`,`birthday`,`sex`,`education`,`telephone`,`interest`,`remark`) values (1,'jack','1234',18,'1996-11-11','男',NULL,NULL,NULL,NULL),(2,'rose','1234',21,'1993-11-11','女',NULL,NULL,NULL,NULL),(3,'tom','1234',23,'1996-12-24','男',NULL,NULL,NULL,NULL);
@Table(name="t_user")
public class User {
@Id
private Integer uid;
private String loginName;
private String loginPwd;
private Integer age;
private String sex;
private String birthday;
private String education;
private String telephone;
private String interest; //爱好:对应数据库(内容:A,B,C)
private String[] interestArr; //爱好:对应页面表单
private String remark;
l 爱好需要特殊处理
public String getInterest() {
if(interestArr != null){
interest = Arrays.toString(interestArr); //[A,B,C]
interest = interest.substring(1, interest.length() - 1); //A,B,C
}
return interest;
}
public void setInterest(String interest) {
this.interest = interest;
if(interest != null){
interestArr = interest.split(", ");
}
}
package com.Maynor.dao;
import com.Maynor.domain.User;
import tk.mybatis.mapper.common.Mapper;
public interface UserMapper extends Mapper {
}
package com.Maynor.service;
import com.Maynor.domain.User;
import java.util.List;
public interface UserService {
public List findAll();
}
package com.Maynor.service.impl;
import com.Maynor.dao.UserMapper;
import com.Maynor.domain.User;
import com.Maynor.service.UserService;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import tk.mybatis.mapper.common.Mapper;
import javax.annotation.Resource;
import java.util.List;
@Service(value = "userServiceImpl")
@Transactional
public class UserServiceImpl implements UserService {
@Resource
private UserMapper userMapper;
@Override
public List findAll() {
List users = userMapper.selectAll();
return users;
}
}
package com.Maynor.controller;
import com.Maynor.domain.User;
import com.Maynor.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import javax.annotation.Resource;
import java.util.List;
@Controller
public class UserController {
@Autowired
private UserService userService;
@RequestMapping("/findAllUsers.action")
public String findAll(Model model){
List userList = userService.findAll();
model.addAttribute("userList", userList);
return "/user/list.jsp";
}
}
List.jsp
Left.jsp
${pageContext.request.contextPath}/findAllUsers.action
package com.Maynor.config;
import com.alibaba.druid.pool.DruidDataSource;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.context.support.PropertySourcesPlaceholderConfigurer;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import org.springframework.transaction.annotation.TransactionManagementConfigurer;
import org.springframework.web.bind.annotation.RequestMapping;
import javax.annotation.Resource;
import javax.sql.DataSource;
//配置类
@Configuration
//要扫描的包
@ComponentScan(basePackages = {"com.Maynor"})
//开启事务支持
@EnableTransactionManagement
//读取properties配置文件
@PropertySource(value = "classpath:db.properties")
public class SpringConfig {
//4.2.4 读取properties的固定代码
@Bean
public static PropertySourcesPlaceholderConfigurer create(){
return new PropertySourcesPlaceholderConfigurer();
}
//读取数据库中的相关配置
@Value("${jdbc.driver}")
private String driverClass;
@Value("${jdbc.url}")
private String url;
@Value("${jdbc.username}")
private String username;
@Value("${jdbc.password}")
private String password;
//设置德鲁伊连接池
@Bean
public DataSource dataSource(){
DruidDataSource dataSource = new DruidDataSource();
dataSource.setPassword(password);
dataSource.setUsername(username);
dataSource.setUrl(url);
dataSource.setDriverClassName(driverClass);
return dataSource;
}
//开启事务管理器
@Bean
@Resource
public DataSourceTransactionManager txManager(DataSource dataSource){
return new DataSourceTransactionManager(dataSource);
}
}
package com.Maynor.config;
import com.alibaba.druid.pool.DruidDataSource;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.context.support.PropertySourcesPlaceholderConfigurer;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import org.springframework.transaction.annotation.TransactionManagementConfigurer;
import org.springframework.web.bind.annotation.RequestMapping;
import javax.annotation.Resource;
import javax.sql.DataSource;
//配置类
@Configuration
//要扫描的包
@ComponentScan(basePackages = {"com.Maynor"})
//开启事务支持
@EnableTransactionManagement
//读取properties配置文件
@PropertySource(value = "classpath:db.properties")
public class SpringConfig {
//4.2.4 读取properties的固定代码
@Bean
public static PropertySourcesPlaceholderConfigurer create(){
return new PropertySourcesPlaceholderConfigurer();
}
//读取数据库中的相关配置
@Value("${jdbc.driver}")
private String driverClass;
@Value("${jdbc.url}")
private String url;
@Value("${jdbc.username}")
private String username;
@Value("${jdbc.password}")
private String password;
//设置德鲁伊连接池
@Bean
public DataSource dataSource(){
DruidDataSource dataSource = new DruidDataSource();
dataSource.setPassword(password);
dataSource.setUsername(username);
dataSource.setUrl(url);
dataSource.setDriverClassName(driverClass);
return dataSource;
}
//开启事务管理器
@Bean
@Resource
public DataSourceTransactionManager txManager(DataSource dataSource){
return new DataSourceTransactionManager(dataSource);
}
}
package com.Maynor.config;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
//声明为配置类
@Configuration
//设置扫描 controller
@ComponentScan("com.Maynor.controller")
public class SpringMvcConfig {
}
传统Web项目中,程序的入口是web.xml文件。
在spring4中提供WebApplicationInitializer接口,表示服务器启动初始化。也就是说接口实现类中编写的内容,就是web.xml文件中配置的内容。
类或方法 | 描述 |
---|---|
AnnotationConfigWebApplicationContext | WEB环境下spring工厂 |
servletContext.addFilter(name , Class) | 添加过滤器,等效 |
servletContext.addServlet(name , Class) | 添加servlet,等效 |
过滤器相关方法 ServletRegistration.Dynamic | 描述 |
---|---|
addMapping(urlPatterns) | 追加过滤路径 |
setLoadOnStartup(int) | 设置启动顺序 |
过滤器相关方法 FilterRegistration.Dynamic | 描述 |
---|---|
addMappingForUrlPatterns(null, isMatchAfter, urlPatterns) | 追加过滤路径参数2:参数3:路径 |
package com.Maynor.config;
import org.springframework.web.WebApplicationInitializer;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.filter.CharacterEncodingFilter;
import org.springframework.web.servlet.DispatcherServlet;
import javax.servlet.FilterRegistration;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRegistration;
public class WebInitializer implements WebApplicationInitializer {
@Override
public void onStartup(ServletContext servletContext) throws ServletException {
//1.初始化 Spring 容器
AnnotationConfigWebApplicationContext applicationContext = new AnnotationConfigWebApplicationContext();
applicationContext.register(SpringMvcConfig.class);
applicationContext.register(SpringConfig.class);
applicationContext.register(MybatisConfig.class);
applicationContext.setServletContext(servletContext);
//2.设置核心控制器
ServletRegistration.Dynamic ds = servletContext.addServlet("springmvc", new DispatcherServlet(applicationContext));
ds.addMapping("*.action");
ds.setLoadOnStartup(2);
//3 post乱码配置
FilterRegistration.Dynamic encodingFilter = servletContext.addFilter("CharacterEncodingFilter", new CharacterEncodingFilter("UTF-8"));
encodingFilter.addMappingForUrlPatterns(null, true, "/*");
}
}
启动项目,点击用户管理 可以看到如下效果即可.
l 其他代码与“查询所有”案例相同,不同内容如下:
l 业务控制器返回“视图”名称
@Controller
@RequestMapping("/user")
public class ItemsController {
@RequestMapping("/itemsList")
public String itemsList(Model model) throws Exception {
//1 模拟数据
List list = new ArrayList();
list.add(new Items("联想笔记本", 6999f, "ThinkPad T430 联想笔记本电脑!"));
list.add(new Items("苹果手机", 8800f, "iphone X 苹果手机!"));
//设置数据
model.addAttribute("list", list);
return "itemslist"; //"/WEB-INF/jsp/itemslist.jsp";
}
}
@Configuration
@ComponentScan("com.Maynor.controller")
public class MVCConfiguration {
@Bean
public InternalResourceViewResolver viewResolver(){
InternalResourceViewResolver viewResolver = new InternalResourceViewResolver();
viewResolver.setPrefix("/WEB-INF/jsp/");
viewResolver.setSuffix(".jsp");
return viewResolver;
}
}
l 在控制器的方法中,只要有对应的参数名,spring mvc就可以自动完成参数封装。
l 参数类型推荐使用包装数据类型,因为基础数据类型不可以为null,此时进行访问没有设置参数,程序抛异常。
数据类型 |
---|
整型:Integer、int |
字符串:String |
单精度:Float、float |
双精度:Double、double |
布尔型:Boolean、boolean |
l 如果请求参数名和方法参数名不一致时,需要使用@RequestParam标记对应关系。
l 如果类型是基本类型,此时没有参数,默认抛异常。
解决方案1:可以设置默认值。
解决方案2:可以设置成 包装类型
JSP页面
控制器:
@Controller
@RequestMapping("/user")
public class ItemsController {
@RequestMapping("additems")
public String addItems(Items items){
System.out.println(items);
return "itemslist";
}
}
l 分析
l 注意:数据不能是日期,日期必须采用自定义参数绑定。
在web.xml文件中
encodingFilter
org.springframework.web.filter.CharacterEncodingFilter
encoding
UTF-8
forceEncoding
true
encodingFilter
/*
我们采用web启动配置类的方式
@Override
public void onStartup(ServletContext servletContext) throws ServletException {
//1 初始化spring容器
AnnotationConfigWebApplicationContext appliation = new AnnotationConfigWebApplicationContext();
appliation.register(MVCConfiguration.class);
appliation.setServletContext(servletContext);
//2 post乱码配置
FilterRegistration.Dynamic encodingFilter = servletContext.addFilter("CharacterEncodingFilter", new CharacterEncodingFilter("UTF-8"));
encodingFilter.addMappingForUrlPatterns(null, true, "/*");
//3 前端控制器
ServletRegistration.Dynamic springMvcServlet = servletContext.addServlet("springmvc", new DispatcherServlet(appliation));
springMvcServlet.addMapping("*.action");
springMvcServlet.setLoadOnStartup(2);
}
提供JavaBean:QueryVo
public class QueryVo {
private Items items;
public Items getItems() {
return items;
}
public void setItems(Items items) {
this.items = items;
}
}
修改控制器
@RequestMapping("findall")
public String findAll(QueryVo queryVo){
System.out.println(queryVo.getItems());
return "itemslist";
}
JSP页面
由于日期数据有很多种格式,所以springmvc没办法把字符串转换成日期类型(不够智能,2019/01/01这种格式可以自动转,2019-01-01这种格式就不能了)。所以需要自定义参数绑定。
JavaBean
public class QueryVo {
private Items items;
private Date createDate;
JSP页面
控制器
@RequestMapping("findall2")
public String findAll2(QueryVo queryVo){
System.out.println(queryVo.getItems());
System.out.println(queryVo.getCreateDate());
return "itemslist";
}
方式一:
\1. 在MVCConfig类上添加@EnableWebMvc 注解
\2. 在实体类上添加注解@DateTimeFormat
JavaBean
public class QueryVo {
private Items items;
private Date createDate;
JSP页面
控制器
@RequestMapping("findall2")
public String findAll2(QueryVo queryVo){
System.out.println(queryVo.getItems());
System.out.println(queryVo.getCreateDate());
return "itemslist";
}
JavaBean
public class QueryVo {
private Items items;
private Date createDate;
JSP页面
控制器
@RequestMapping("findall2")
public String findAll2(QueryVo queryVo){
System.out.println(queryVo.getItems());
System.out.println(queryVo.getCreateDate());
return "itemslist";
}
JavaBean
public class QueryVo {
private Items items;
private Date createDate;
JSP页面
控制器
@RequestMapping("findall2")
public String findAll2(QueryVo queryVo){
System.out.println(queryVo.getItems());
System.out.println(queryVo.getCreateDate());
return "itemslist";
}
l 同时设置多个路径
@RequestMapping(value={"/index","/index2"})
public String index(){
return "itemslist";
}
http://localhost:8080/spring_mvc_day01_05/user/index.action
http://localhost:8080/spring_mvc_day01_05/user/index2.action
//都可以访问
@RequestMapping放在类名上边,设置请求前缀
@RequestMapping放在方法名上边,设置方法对应请求路径。
完整请求:前缀 + 请求路径
l 限定GET方法
@RequestMapping(method = RequestMethod.GET)
l 限定POST方法
@RequestMapping(method = RequestMethod.POST)
l GET和POST都可以
@RequestMapping(method={RequestMethod.GET,RequestMethod.POST})
controller方法中定义ModelAndView对象并返回,对象中可添加model数据、指定view。
@RequestMapping("/findById")
public ModelAndView findById(){
ModelAndView modelAndview = new ModelAndView();
//设置数据
modelAndview.addObject("id", "猜猜看");
//设置视图
modelAndview.setViewName("itemslist");
return modelAndview;
}
如果方法返回void,有3种情况:request请求转发、response重定向、给前端响应Json
请求转发
@RequestMapping("/findById2")
public void findById2(HttpServletRequest request , HttpServletResponse response)
throws ServletException, IOException{
request.getRequestDispatcher("/index.jsp").forward(request, response);
}
重定向
@RequestMapping("/findById3")
public void findById3(HttpServletRequest request , HttpServletResponse response)
throws ServletException, IOException{
response.sendRedirect(request.getContextPath() + "/index.jsp");
}
Json 处理
@RequestMapping("/findById4")
public void findById4(HttpServletRequest request , HttpServletResponse response)
throws ServletException, IOException{
response.setCharacterEncoding("UTF-8");
response.setContentType("application/json;charset=UTF-8");
String jsonStr = "{\"username\":\"jack\"}";
response.getWriter().write(jsonStr);
}
controller方法返回字符串可以指定逻辑视图名,通过视图解析器解析为物理视图地址。
@RequestMapping(value={"/index","/index2"})
public String index(){
return "itemslist";
}
Contrller方法返回结果重定向到一个url地址,如下商品修改提交后重定向到商品查询方法,参数无法带到商品查询方法中。
return "redirect:其他路径";
@RequestMapping("/update")
public String update() throws ServletException, IOException{
return "redirect:queryItem.action";
}
controller方法执行后继续执行另一个controller方法,如下商品修改提交后转向到商品修改页面,修改商品的id参数可以带到商品修改方法中。
return "forward:其他路径";
@RequestMapping("/updateSubmit")
public String updateSubmit() throws ServletException, IOException{
return "forward:editItem.action";
}
public class CustomException extends Exception {
private static final long serialVersionUID = 8222256702797084775L;
public CustomException() {
super();
}
public CustomException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
super(message, cause, enableSuppression, writableStackTrace);
}
public CustomException(String message, Throwable cause) {
super(message, cause);
}
public CustomException(String message) {
super(message);
}
public CustomException(Throwable cause) {
super(cause);
}
}
public class CustomException extends Exception {
private static final long serialVersionUID = 8222256702797084775L;
public CustomException() {
super();
}
public CustomException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
super(message, cause, enableSuppression, writableStackTrace);
}
public CustomException(String message, Throwable cause) {
super(message, cause);
}
public CustomException(String message) {
super(message);
}
public CustomException(Throwable cause) {
super(cause);
}
}
您的操作出现错误如下:
${message }
@Controller
@RequestMapping("/user")
public class ItemsController {
@RequestMapping("index")
public String index(String id) throws CustomException{
if(id == null){
throw new CustomException("没有id参数");
}
return "itemslist";
}
}
异常演示
异常演示
l 使用的commons-fileupload完成上传,确定导入fileupload jar包
commons-fileupload
commons-fileupload
1.2.2
commons-io
commons-io
2.3
需要使用MultipartFile类型表示一个文件上传对象。
方法名 | 描述 |
---|---|
String getOriginalFilename() | 获得原始上传文件名 |
transferTo(File file) | 将上传文件转换到一个指定的文件中 |
String getContentType() | 获取文件MIME类型,如image/pjpeg、text/plain等 |
String getName() | 获取表单中文件组件的名字 |
@RequestMapping("upload")
public String upload(String name,Double price,
@RequestParam(required=false,value="picFile") MultipartFile picFile) throws Exception{
System.out.println("姓名:" + name);
System.out.println("价格:" + price);
String originalFileName = picFile.getOriginalFilename();
System.out.println("上传文件名:" + originalFileName);
//保存文件到指定的位置
File file = new File("D:\\temp", originalFileName);
picFile.transferTo(file);
return "itemslist";
}
public class QueryVo {
private String name;
private Double price;
public List picFile;
//getter and setter
@RequestMapping("upload2")
public String upload2(QueryVo queryVo) throws Exception{
System.out.println("姓名:" + queryVo.getName());
System.out.println("价格:" + queryVo.getPrice());
System.out.println("上传文件个数:" + queryVo.getPicFile().size());
for(MultipartFile picFile : queryVo.getPicFile()){
String originalFileName = picFile.getOriginalFilename();
System.out.println("上传文件名:" + originalFileName);
//保存文件到指定的位置
File file = new File("D:\\temp", originalFileName);
picFile.transferTo(file);
}
return "itemslist";
}
@RequestBody:将json、xml 等内容 转换 成Java对象。
@ResponseBody:将Java对象 转换 成 json、xml等内容。
需求:
前端发送ajax请求,后端通过VO自动获取数据打印
前端代码:
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
Title
页面加载完毕就发射ajax
后端代码:
Qvo
public class QVo {
private String name;
private Double price;
....
}
Controller
@RequestMapping("/tJson.action")
public String testJson(QVo qvo){
//查看前端传递的json 自动转化的VO结果
System.out.println(qvo);
return "/show04.jsp";//随便转发到一个页面,不影响测试结果.
}
测试结果:
需求:
跟上一个例子类似, 前端发送请求给后端, 后端接收数据后给前端再相应回一个json数据.
该例子中,需要直接把java对象通过SpringMvc自动转化成json数据. 需要使用两个东西完成.
\1. 导入Jackson-databind坐标
\2. 在方法的返回值上使用@ResponseBody注解.
具体代码如下:
Pom文件坐标
com.fasterxml.jackson.core
jackson-databind
2.9.7
Controller代码:
@RequestMapping("tj.action")
public @ResponseBody QVo getInfo(String name,Double price){
System.out.println("接收到前端数据:"+name+" "+price);
//创建一个对象, 通过SpringMvc自动把这个对象转化成Json响应给前端
QVo qVo = new QVo("lisiguang", 220.4);
return qVo;
}
前端:
测试结果:
后端:
前端:
Restful就是一个资源定位及资源操作的风格。不是标准也不是协议,只是一种风格,是对http协议的诠释。
l 资源定位:每一个URL都是一个资源。要求url中没有动词,只有名词。没有参数
Url格式:http://blog.csdn.net/beat_the_world/article/details/45621673
l 资源操作:通过HTTP请求方式确定不同的操作。
get查询资源、post新建资源(也可以修改资源)、put更新资源、delete删除资源。
一般使用时还是post和get。
@RequestMapping(value="/viewItems/{id}" , method= RequestMethod.GET )
l RESTful初体验
在URL中包含操作的数据,而不是通过参数进行传递。
springmvc
org.springframework.web.servlet.DispatcherServlet
contextConfigLocation
classpath:springmvc.xml
springmvc
/
Insert title here
查询id=1
查询id=999
通过@RequestMapping可以设置URL模板模式映射。
@RequestMapping(value="/ viewItems/{xxx}") ,{xxx}相当于占位符,可以匹配到/viewItems/1、/viewItems/2 等路径
xxx就是占位符的名称,用于方法参数获得匹配到的数据
通过@PathVariable(“xxx”) 获得从路径匹配到的对应数据
@RequestMapping("/viewItems/{id}")
public String viewItems(@PathVariable("id") String id , Model model) {
model.addAttribute("id", id);
return "itemslist";
}
l 当程序运行时,首页的js代码将不能执行。
原因:DispatcherServlet中设置url-pattern为 /,静态资源不能成功访问。
解决:配置 mvc:resources
Spring Web MVC 的处理器拦截器类似于Servlet 开发中的过滤器Filter,用于对处理器执行前后进行处理。
自定义连接性需要实现接口:HandlerInterceptor
方法名 | 描述 |
---|---|
boolean preHandle() | 在处理器(控制器)前执行。返回一个boolean值。true:继续执行处理器。false:程序直接结束。 |
void postHandle() | 在处理器方法执行后,视图显示前执行。 |
void afterCompletion() | 在视图解析成功后执行。 |
拦截器演示
@Controller
@RequestMapping("/user")
public class ItemsController {
@RequestMapping("index")
public String index(String id) {
System.out.println("2.controller");
return "itemslist";
}
}
package com.Maynor.interceptor;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@Component
public class MyInterceptor1 implements HandlerInterceptor {
/*
* 在方法执行之前执行
* 如果返回true 继续执行下一个拦截器
* 如果返回false,请求被终止
* @param request
* @param response
* @param handler
* @return
* @throws Exception
*/
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
System.out.println("MyInterceptor1拦截器的preHandle");
return true;
}
@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
System.out.println("MyInterceptor1拦截器的postHandle");
}
@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
System.out.println("MyInterceptor1拦截器的afterCompletion");
}
}
拦截器编写完成之后,需要在SpringMVCConfiguration配置文件中注册
注册步骤:
1 SpringMVCConfiguration实现WebMvcConfigurerAdapter
2 重写AddInterceptors方法
public class SpringMvcConfig extends WebMvcConfigurerAdapter {
@Autowired
private MyInterceptor1 myInterceptor1;
@Override
public void addInterceptors(InterceptorRegistry registry) {
InterceptorRegistration interceptorRegistration1 = registry.addInterceptor(myInterceptor1);
interceptorRegistration1.addPathPatterns("/*");
}
//.....
}
package com.Maynor.interceptor;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@Component
public class MyInterceptor2 implements HandlerInterceptor {
/*
* 在方法执行之前执行
* 如果返回true 继续执行下一个拦截器
* 如果返回false,则程序终止
* @param request
* @param response
* @param handler
* @return
* @throws Exception
*/
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
System.out.println("MyInterceptor2拦截器的preHandle");
return true;
}
@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
System.out.println("MyInterceptor2拦截器的postHandle");
}
@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
System.out.println("MyInterceptor2拦截器的afterCompletion");
}
}
@Resource
private MyInterceptor1 myInterceptor1;
@Resource
private MyInterceptor2 myInterceptor2;
@Override
public void addInterceptors(InterceptorRegistry registry) {
//拦截全部
InterceptorRegistration interceptorRegistration2 = registry.addInterceptor(myInterceptor2);
interceptorRegistration2.addPathPatterns("/*");
//拦截全部
InterceptorRegistration interceptorRegistration = registry.addInterceptor(myInterceptor1);
interceptorRegistration.addPathPatterns("/*");
}
用到的相关配置文件
SpringMVC入门案例1的pom文件核心代码
Pom.xml文件
<properties>
<org.springframework.version>4.2.4.RELEASEorg.springframework.version>
properties>
<dependencies>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-beansartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-coreartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-contextartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-expressionartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-context-supportartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-aopartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-aspectsartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-instrumentartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-messagingartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-jdbcartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-ormartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-oxmartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-jmsartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-txartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-websocketartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-webartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-webmvc-portletartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-webmvcartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-testartifactId>
<version>${org.springframework.version}version>
dependency>
<dependency>
<groupId>junitgroupId>
<artifactId>junitartifactId>
<version>4.12version>
<scope>testscope>
dependency>
<dependency>
<groupId>tk.mybatisgroupId>
<artifactId>mapperartifactId>
<version>3.5.2version>
dependency>
<dependency>
<groupId>com.github.pagehelpergroupId>
<artifactId>pagehelperartifactId>
<version>3.7.5version>
dependency>
<dependency>
<groupId>org.mybatisgroupId>
<artifactId>mybatisartifactId>
<version>3.4.5version>
dependency>
<dependency>
<groupId>mysqlgroupId>
<artifactId>mysql-connector-javaartifactId>
<version>5.1.47version>
dependency>
<dependency>
<groupId>org.mybatisgroupId>
<artifactId>mybatis-springartifactId>
<version>1.3.2version>
dependency>
<dependency>
<groupId>com.alibabagroupId>
<artifactId>druidartifactId>
<version>1.1.10version>
dependency>
<dependency>
<groupId>javax.servletgroupId>
<artifactId>javax.servlet-apiartifactId>
<version>3.1.0version>
<scope>providedscope>
dependency>
<dependency>
<groupId>jstlgroupId>
<artifactId>jstlartifactId>
<version>1.2version>
dependency>
dependencies>
<plugin>
<groupId>org.apache.maven.pluginsgroupId>
<artifactId>maven-compiler-pluginartifactId>
<version>3.2version>
<configuration>
<source>1.8source>
<target>1.8target>
<encoding>UTF-8encoding>
<showWarnings>trueshowWarnings>
configuration>
plugin>
<plugin>
<groupId>org.apache.tomcat.mavengroupId>
<artifactId>tomcat7-maven-pluginartifactId>
<version>2.1version>
<configuration>
<port>8080port>
<server>tomcat7server>
configuration>
plugin>
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