SSM整合指的是将Spring、Spring MVC、MyBatis三个框架集成在一起,以便更好地开发Java Web应用程序。它们之间的整合可以提高开发效率,简化配置,减少重复代码,提高代码重用性。Spring作为IoC容器和AOP框架,可以管理Bean的生命周期,简化代码结构;Spring MVC作为Web框架,可以方便地处理请求和响应;MyBatis作为持久层框架,可以简化数据库操作。SSM整合后,可以通过注解来简化配置,使开发更加高效快速。
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.encoding>UTF-8</maven.compiler.encoding>
<spring.version>5.2.10.RELEASE</spring.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.5.6</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>1.3.0</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.47</version>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.1.16</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.1.0</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.18.16</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.9.0</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.tomcat.maven</groupId>
<artifactId>tomcat7-maven-plugin</artifactId>
<version>2.2</version>
<configuration>
<!-- 端口号 -->
<port>80</port>
<!-- 模块的访问地址 -->
<path>/</path>
<!-- GET方法不会乱码问题 -->
<uriEncoding>utf-8</uriEncoding>
</configuration>
</plugin>
</plugins>
</build>
-- 创建ssm_db数据库
CREATE DATABASE IF NOT EXISTS ssm_db CHARACTER SET utf8;
-- 使用ssm_db数据库
USE ssm_db;
-- 创建tbl_book表
CREATE TABLE tbl_book(
id INT PRIMARY KEY AUTO_INCREMENT, -- 图书编号
`type` VARCHAR(100), -- 图书类型
`name` VARCHAR(100), -- 图书名称
description VARCHAR(100) -- 图书描述
);
-- 添加初始化数据
INSERT INTO tbl_book VALUES(NULL,'计算机理论','Spring实战 第5版','Spring入门经典教材,深入理解Spring原理技术内幕');
INSERT INTO tbl_book VALUES(NULL,'计算机理论','Spring 5核心原理与30个类手写实战','十年沉淀之作,手写Spring精华思想');
INSERT INTO tbl_book VALUES(NULL,'计算机理论','Spring 5设计模式','深入Spring源码剖析,Spring源码蕴含的10大设计模式');
INSERT INTO tbl_book VALUES(NULL,'市场营销','直播就该这么做:主播高效沟通实战指南','李子柒、李佳琦、薇娅成长为网红的秘密都在书中');
INSERT INTO tbl_book VALUES(NULL,'市场营销','直播销讲实战一本通','和秋叶一起学系列网络营销书籍');
INSERT INTO tbl_book VALUES(NULL,'市场营销','直播带货:淘宝、天猫直播从新手到高手','一本教你如何玩转直播的书,10堂课轻松实现带货月入3W+');
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/ssm_db
jdbc.username=root
jdbc.password=root
@PropertySource("classpath:jdbc.properties")
public class JdbcConfig {
@Value("${jdbc.driver}")
private String driver;
@Value("${jdbc.url}")
private String url;
@Value("${jdbc.username}")
private String username;
@Value("${jdbc.password}")
private String password;
//配置连接池
@Bean
public DataSource dataSource(){
DruidDataSource dataSource = new DruidDataSource();
dataSource.setDriverClassName(driver);
dataSource.setUrl(url);
dataSource.setUsername(username);
dataSource.setPassword(password);
return dataSource;
}
//Spring事务管理需要的平台事务管理器对象
@Bean
public PlatformTransactionManager transactionManager(DataSource dataSource){
DataSourceTransactionManager ds = new DataSourceTransactionManager();
ds.setDataSource(dataSource);
return ds;
}
}
public class MybatisConfig {
@Bean
public SqlSessionFactoryBean sqlSessionFactory(DataSource dataSource){
SqlSessionFactoryBean factoryBean = new SqlSessionFactoryBean();
factoryBean.setDataSource(dataSource);
factoryBean.setTypeAliasesPackage("com.itheima.domain");
//创建配置对象
Configuration configuration = new Configuration();
//开启日志记录,显示SQL语句
configuration.setLogImpl(StdOutImpl.class);
//设置列名下划线与驼峰命名对应
configuration.setMapUnderscoreToCamelCase(true);
//指定工厂的配置对象
factoryBean.setConfiguration(configuration);
return factoryBean;
}
@Bean
public MapperScannerConfigurer mapperScannerConfigurer(){
MapperScannerConfigurer msc = new MapperScannerConfigurer();
msc.setBasePackage("com.itheima.dao");
return msc;
}
}
@Configuration
//排除Controller
@ComponentScan(value = "com.itheima.service")
@Import({JdbcConfig.class,MybatisConfig.class})
@EnableTransactionManagement //开启Spring事务管理
public class SpringConfig {
}
注:如果Spring的配置文件中,使用排除Controller的这种方式
@ComponentScan(basePackages = "com.itheima", excludeFilters = @ComponentScan.Filter(Controller.class))
会与@EnableWebMvc冲突,导致业务层测试失败
@Configuration
@ComponentScan("com.itheima.controller")
@EnableWebMvc //导入SpringMVC的配置
public class SpringMvcConfig {
}
public class ServletConfig extends AbstractDispatcherServletInitializer {
@Override
protected WebApplicationContext createServletApplicationContext() {
AnnotationConfigWebApplicationContext ac = new AnnotationConfigWebApplicationContext();
ac.register(SpringMvcConfig.class);
return ac;
}
@Override
protected String[] getServletMappings() {
return new String[]{"/"};
//“/”,可以拦截除了jsp以外所有的资源的请求,拦截这些请求的目的是交给springmvc去处理
}
@Override
protected WebApplicationContext createRootApplicationContext() {
AnnotationConfigWebApplicationContext ac = new AnnotationConfigWebApplicationContext();
ac.register(SpringConfig.class);
return ac;
}
//配置springmvc框架提供的处理post请求中文乱码过滤器
@Override
protected Filter[] getServletFilters() {
CharacterEncodingFilter characterEncodingFilter = new CharacterEncodingFilter();
characterEncodingFilter.setEncoding("utf-8");
return new Filter[]{characterEncodingFilter};
}
}
@Data
public class Book {
private Integer id;
private String type;
private String name;
private String description;
}
public interface BookDao {
@Insert("insert into tbl_book values(null,#{type},#{name},#{description})")
public int save(Book book); //返回值表示影响的行数
@Update("update tbl_book set type = #{type}, name = #{name}, description = #{description} where id = #{id}")
public int update(Book book);
@Delete("delete from tbl_book where id = #{id}")
public int delete(Integer id);
@Select("select * from tbl_book where id = #{id}")
public Book getById(Integer id);
@Select("select * from tbl_book")
public List<Book> getAll();
}
@Transactional //表示所有方法进行事务管理
public interface BookService {
/**
* 保存
* @param book
* @return
*/
public boolean save(Book book);
/**
* 修改
* @param book
* @return
*/
public boolean update(Book book);
/**
* 按id删除
* @param id
* @return
*/
public boolean delete(Integer id);
/**
* 按id查询
* @param id
* @return
*/
public Book getById(Integer id);
/**
* 查询全部
* @return
*/
public List<Book> getAll();
}
@Service
public class BookServiceImpl implements BookService {
@Autowired
private BookDao bookDao;
public boolean save(Book book) {
bookDao.save(book);
return true;
}
public boolean update(Book book) {
bookDao.update(book);
return true;
}
public boolean delete(Integer id) {
bookDao.delete(id);
return true;
}
public Book getById(Integer id) {
return bookDao.getById(id);
}
public List<Book> getAll() {
return bookDao.getAll();
}
}
@RestController
@RequestMapping("/books")
public class BookController {
@Autowired
private BookService bookService;
@PostMapping
public boolean save(@RequestBody Book book) {
return bookService.save(book);
}
@PutMapping
public boolean update(@RequestBody Book book) {
return bookService.update(book);
}
@DeleteMapping("/{id}")
public boolean delete(@PathVariable Integer id) {
return bookService.delete(id);
}
@GetMapping("/{id}")
public Book getById(@PathVariable Integer id) {
return bookService.getById(id);
}
@GetMapping
public List<Book> getAll() {
return bookService.getAll();
}
}
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = SpringConfig.class)
public class BookServiceTest {
@Autowired
private BookService bookService;
@Test
public void testGetById(){
Book book = bookService.getById(1);
System.out.println(book);
}
@Test
public void testGetAll(){
List<Book> all = bookService.getAll();
System.out.println(all);
}
}
这里就以保存图书为例,其他接口同学们自己测试
注:使用tomcat7插件,控制台SQL语句出现乱码,进行以下设置
然后在maven中clean一次再执行
问题:我们表现层增删改方法返回true或者false表示是否成功,getById()方法返回一个json对象,getAll()方法返回一个json对象数组,这里就出现了三种格式的响应结果,极其不利于前端解析。
解决:我们需要统一响应结果的格式
/**
* 封装结果信息
*/
@Data
public class Result {
//描述统一格式中的数据
private Object data;
//描述统一格式中的编码,用于区分操作,可以简化配置0或1表示成功失败
private Integer code;
//描述统一格式中的消息,可选属性
private String msg;
public Result() {
}
//状态码,数据
public Result(Integer code, Object data) {
this.data = data;
this.code = code;
}
//状态码,数据,信息
public Result(Integer code, Object data, String msg) {
this.data = data;
this.code = code;
this.msg = msg;
}
}
注意事项:
Result类中的字段并不是固定的,可以根据需要自行增减
package com.itheima.domain;
//状态码
public interface Code {
Integer SAVE_OK = 20011;
Integer DELETE_OK = 20021;
Integer UPDATE_OK = 20031;
Integer GET_OK = 20041;
Integer SAVE_ERR = 20010;
Integer DELETE_ERR = 20020;
Integer UPDATE_ERR = 20030;
Integer GET_ERR = 20040;
}
注意事项:
Code类的常量设计也不是固定的,可以根据需要自行增减,例如将查询再进行细分为GET_OK,GET_ALL_OK,GET_PAGE_OK
@RestController
@RequestMapping("/books")
public class BookController {
@Autowired
private BookService bookService;
@PostMapping
public Result save(@RequestBody Book book) {
boolean flag = bookService.save(book);
//参数1:如果为真,返回添加成功,否则返回失败。参数2:数据 true或false
return new Result(flag ? Code.SAVE_OK:Code.SAVE_ERR, flag);
}
@PutMapping
public Result update(@RequestBody Book book) {
boolean flag = bookService.update(book);
return new Result(flag ? Code.UPDATE_OK:Code.UPDATE_ERR,flag);
}
@DeleteMapping("/{id}")
public Result delete(@PathVariable Integer id) {
boolean flag = bookService.delete(id);
return new Result(flag ? Code.DELETE_OK:Code.DELETE_ERR,flag);
}
@GetMapping("/{id}")
public Result getById(@PathVariable Integer id) {
Book book = bookService.getById(id);
//对象不为空表示成功,否则表示失败
Integer code = book != null ? Code.GET_OK : Code.GET_ERR;
//封装消息:对象不为空返回空串,否则返回查询失败
String msg = book != null ? "" : "数据查询失败,请重试!";
//状态码,数据,信息
return new Result(code,book,msg);
}
@GetMapping
public Result getAll() {
List<Book> bookList = bookService.getAll();
//集合不为空则返回成功
Integer code = bookList != null ? Code.GET_OK : Code.GET_ERR;
//集合不为空返回空串,否则返回查询失败
String msg = bookList != null ? "" : "数据查询失败,请重试!";
//状态码,数据,信息
return new Result(code,bookList,msg);
}
}
@RestControllerAdvice是对Controller进行增强的,可以全局捕获spring mvc抛的异常。并匹配相应的@ExceptionHandler中指定的异常类型,重新封装异常信息,将统一格式返回给前端。
这个类所在的包要能够被Spring MVC扫描到
@RestControllerAdvice //用于标识当前类为REST风格对应的异常处理器
public class ProjectExceptionAdvice {
//统一处理所有的Exception异常
@ExceptionHandler(Exception.class)
public Result doOtherException(Exception ex) {
//状态码,数据,信息
return new Result(666, null, ex.getMessage());
}
}
使用异常处理器之后的效果
//自定义异常处理器,用于封装异常信息,对异常进行分类
public class SystemException extends RuntimeException{
//异常的编码
@Getter @Setter
private Integer code;
//两个参数的构造方法:状态码,信息
public SystemException(Integer code, String message) {
super(message);
this.code = code;
}
//三个参数的构造方法:状态码,信息,异常
public SystemException(Integer code, String message, Throwable cause) {
super(message, cause);
this.code = code;
}
}
//自定义异常处理器,用于封装异常信息,对异常进行分类
public class BusinessException extends RuntimeException{
@Getter @Setter
private Integer code;
public BusinessException(Integer code, String message) {
super(message);
this.code = code;
}
public BusinessException(Integer code,String message,Throwable cause) {
super(message, cause);
this.code = code;
}
}
//状态码
public interface Code {
Integer SYSTEM_ERR = 50001;
Integer SYSTEM_TIMEOUT_ERR = 50002;
Integer SYSTEM_UNKNOW_ERR = 59999;
Integer BUSINESS_ERR = 60002;
}
@Service
public class BookServiceImpl implements BookService {
@Autowired
private BookDao bookDao;
//在getById演示触发异常,其他方法省略没有写进来
public Book getById(Integer id) {
//模拟业务异常,包装成自定义异常
if(id < 0){
throw new BusinessException(Code.BUSINESS_ERR,"请不要使用你的技术挑战我的耐性!");
}
}
}
分别写三个方法用来捕获每种异常
@RestControllerAdvice //用于标识当前类为REST风格对应的异常处理器
public class ProjectExceptionAdvice {
//@ExceptionHandler用于设置当前处理器类对应的异常类型
@ExceptionHandler(SystemException.class)
public Result doSystemException(SystemException ex){
//记录日志
System.out.println("出现系统级异常");
//发送消息给运维
//发送邮件给开发人员,ex对象发送给开发人员
return new Result(ex.getCode(),null,ex.getMessage());
}
@ExceptionHandler(BusinessException.class)
public Result doBusinessException(BusinessException ex){
System.out.println("出现业务级异常");
return new Result(ex.getCode(),null,ex.getMessage());
}
//除了自定义的异常处理器,保留对Exception类型的异常处理,用于处理非预期的异常
@ExceptionHandler(Exception.class)
public Result doOtherException(Exception ex){
//记录日志
System.out.println("出现其它未知异常");
//发送消息给运维
//发送邮件给开发人员,ex对象发送给开发人员
return new Result(Code.SYSTEM_UNKNOW_ERR,null,"系统繁忙,请稍后再试!");
}
}
修改SpringMvcConfig配置文件,扫描上面类所在包,也可以将上面的类放在controller包中
@Configuration
@ComponentScan({"com.itheima.controller", "com.itheima.common"})
@EnableWebMvc //开启json转换
public class SpringMvcConfig {
}
测试:在postman中发送请求访问getById方法,传递参数-1,得到以下结果:
为了确保静态资源能够被访问到,需要设置静态资源过滤
注:资源的真实路径要以/结尾
@Configuration
public class SpringMvcSupport extends WebMvcConfigurationSupport {
@Override
protected void addResourceHandlers(ResourceHandlerRegistry registry) {
registry.addResourceHandler("/pages/**").addResourceLocations("/pages/");
registry.addResourceHandler("/css/**").addResourceLocations("/css/");
registry.addResourceHandler("/js/**").addResourceLocations("/js/");
registry.addResourceHandler("/plugins/**").addResourceLocations("/plugins/");
}
}
修改SpringMvcConfig配置类,添加config包的扫描
@Configuration
@ComponentScan({"com.itheima.controller","com.itheima.common","com.itheima.config"})
@EnableWebMvc
public class SpringMvcConfig {
}
注:为了避免业务类创建2次,可以将SpringMvcConfig配置类和SpringConfig配置类上的@Configuration注解去了,只由ServletConfigInitializer加载
@Service
public class BookServiceImpl implements BookService {
@Autowired
private BookDao bookDao;
//增删改的方法判断了影响的行数是否大于0,而不是固定返回true
public boolean save(Book book) {
return bookDao.save(book) > 0;
}
//增删改的方法判断了影响的行数是否大于0,而不是固定返回true
public boolean update(Book book) {
return bookDao.update(book) > 0;
}
//增删改的方法判断了影响的行数是否大于0,而不是固定返回true
public boolean delete(Integer id) {
return bookDao.delete(id) > 0;
}
public Book getById(Integer id) {
if(id < 0){
throw new BusinessException(Code.BUSINESS_ERR,"请不要使用你的技术挑战我的耐性!");
return bookDao.getById(id);
}
}
public List<Book> getAll() {
return bookDao.getAll();
}
}
使用axios.get()方法
//列表
getAll() {
axios.get("/books").then(resp => {
let result = resp.data;
if (result.code == 20041) {
this.dataList = result.data;
}
});
}
使用axios.post方法
//弹出添加窗口
handleCreate() {
//显示对话框
this.dialogFormVisible = true;
//表单内容清空
this.resetForm();
},
//重置表单
resetForm() {
this.formData = {};
},
//添加
handleAdd () {
//发送ajax请求
axios.post("/books",this.formData).then((res)=>{
console.log(res.data);
//如果操作成功,关闭弹层,显示数据
if(res.data.code == 20011){
this.dialogFormVisible = false;
this.$message.success("添加成功");
}else {
this.$message.error("添加失败");
}
}).finally(()=>{
//无论添加成功还是失败都再次获取数据
this.getAll();
});
},
使用 axios.get方法
//弹出编辑窗口
handleUpdate(row) {
//查询数据,根据id查询
axios.get("/books/"+row.id).then((res)=>{
// console.log(res.data.data);
if(res.data.code == 20041){
//展示弹层,加载数据
this.formData = res.data.data;
this.dialogFormVisible4Edit = true;
}else{
this.$message.error(res.data.msg);
}
});
}
使用axios.put方法
//编辑
handleEdit() {
//发送ajax请求
axios.put("/books",this.formData).then((res)=>{
//如果操作成功,关闭弹层,显示数据
if(res.data.code == 20031){
this.dialogFormVisible4Edit = false;
this.$message.success("修改成功");
}else if(res.data.code == 20030){
this.$message.error("修改失败");
}else{
this.$message.error(res.data.msg);
}
}).finally(()=>{
this.getAll();
});
}
使用axios.delete方法
// 删除
handleDelete(row) {
//1.弹出提示框
this.$confirm("此操作永久删除当前数据,是否继续?","提示",{
type:'info'
}).then(()=>{
//2.做删除业务
axios.delete("/books/"+row.id).then((res)=>{
if(res.data.code == 20021){
this.$message.success("删除成功");
}else{
this.$message.error("删除失败");
}
}).finally(()=>{
this.getAll();
});
}).catch(()=>{
//3.取消删除
this.$message.info("取消删除操作");
});
}