代码已经完善,文章内容会在后续补充
代码地址(https://javazhang.lanzn.com/ig8tf1wd2aba
密码:1234)
1.1 .SpringConfig 代码
@Configuration
@ComponentScan({"com.itheima.service" })
@PropertySource("classpath:jdbc.properties")
@Import({JdbcConfig.class, MyBatisConfig.class})
@EnableTransactionManagement
public class SpringConfig {
}
第一个注解: 设置当前类为配置类
第二个:包扫描识别Spring组件类
第三个:加载外部配置文件
第四个:导配置包(导入service 是为了自动装配能够找到它 , 在后续代码中有用到service类的代码 , 需要用到自动装配)
第五个:开启事务
1.2JdbcConfig
package com.itheima.config;import com.alibaba.druid.pool.DruidDataSource;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.PlatformTransactionManager;import javax.sql.DataSource;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;@Beanpublic DataSource dataSource(){DruidDataSource ds = new DruidDataSource();ds.setDriverClassName(driver);ds.setUrl(url);ds.setUsername(username);ds.setPassword(password);return ds;}@Beanpublic PlatformTransactionManager transactionManager(DataSource dataSource){DataSourceTransactionManager ds = new DataSourceTransactionManager();//这里的dataSourse不能用方法调 因为用发放调就会脱离Spring管理 就不是一个东西ds.setDataSource(dataSource);return ds;}
第二个方法是用来配合事务管理的
1.3 MyBatisConfig
package com.itheima.config;import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.mapper.MapperScannerConfigurer;
import org.springframework.context.annotation.Bean;import javax.sql.DataSource;public class MyBatisConfig {@Beanpublic SqlSessionFactoryBean sqlSessionFactoryBean(DataSource dataSource){SqlSessionFactoryBean ssfb = new SqlSessionFactoryBean();ssfb.setDataSource(dataSource);//类型别名ssfb.setTypeAliasesPackage("com.itheima.domain");return ssfb;}@Beanpublic MapperScannerConfigurer mapperScannerConfigurer(){MapperScannerConfigurer msc = new MapperScannerConfigurer();//指定映射从哪加载msc.setBasePackage("com.itheima.dao");return msc;}
}
这个类是为了在Spring类中集成MyBatis的
第一个方法 创建与数据交互用到的sqlsession
为类型起别名 简化sql语句类型引用
第二个方法 为了绑定mapper的类 ,mapper中做到了进行数据库操作等内容
1.4 jdbc配置类
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/ssm_db
jdbc.username=root
jdbc.password=1234
2.1 ServletConfig
package com.itheima.config;import org.springframework.web.servlet.support.AbstractAnnotationConfigDispatcherServletInitializer;/*** 外部容器配置类*/
public class ServletConfig extends AbstractAnnotationConfigDispatcherServletInitializer {//记载spring配置类protected Class<?>[] getRootConfigClasses() {return new Class[]{SpringConfig.class};}//web容器加载SpringMvcconfigprotected Class<?>[] getServletConfigClasses() {return new Class[]{SpringMvcConfig.class};}//拦截请求归谁管protected String[] getServletMappings() {return new String[]{"/"};}
}
第一个方法指定SpringConfig 的配置类
第二个指定SpringMVC配置类
第三个指定Spring mvc响应哪些请求
SpringMvc:为构建web项目提供了一个完整的流程
2.2SpringMvcConfig
SpringMvc 配置类
package com.itheima.config;import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;@Configuration
@ComponentScan({"com.itheima.controller" , "com.itheima.config"})
@EnableWebMvc
public class SpringMvcConfig {}
第一个注解: 表明当前类为配置类
第二个注解:扫描包下的组件
第三个注解:功能很强大,开启mvc功能 , 暂时用到解析JSON数据
SpringMvcSupport
package com.itheima.config;import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport;@Configuration
public class SpringMvcSupport extends WebMvcConfigurationSupport {@Overrideprotected void addResourceHandlers(ResourceHandlerRegistry registry) {registry.addResourceHandler("/pages/**").addResourceLocations("/pages/");registry.addResourceHandler("/css/**").addResourceLocations("/css/");registry.addResourceHandler("/js/**").addResourceLocations("/js/");registry.addResourceHandler("/plugins/**").addResourceLocations("/plugins/");}
}
用来响应前端代码 , 告诉他访问目录与去哪个文件找
controller类:
1.BookController
package com.itheima.controller;import com.itheima.domain.Book;
import com.itheima.service.BookService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;import java.util.List;/*** 控制器类*/
@RestController
@RequestMapping("/books")
public class BookController {@Autowiredprivate BookService bookService;// 这里面的参数从Json数据中来 所以从@RequestBody 请求体中获得@PostMappingpublic Result save(@RequestBody Book book) {boolean flag = bookService.save(book);return new Result(flag? Code.SAVE_OK:Code.SAVE_ERR,flag);}@PutMappingpublic Result update(@RequestBody Book book) {boolean flag = bookService.update(book);return new Result(flag? Code.UPDATE_OK:Code.UPDATE_ERR , flag) ;}// 这种是路径参数 所以从@PathVariable(英文翻译是路径参数) 中获得@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);Integer code = book != null ? Code.GET_OK : Code.GET_ERR;String msg = book != null ? "":"数据查询失败,请重试";return new Result(code , book , msg);}@GetMappingpublic Result getAll() {List<Book> book = bookService.getAll();Integer code = book != null ? Code.GET_OK : Code.GET_ERR;String msg = book != null ? "" :"数据查询失败,请重试";return new Result(code,book,msg);}
}
使用了Rest风格简化开发 统一规范
Rest风格个人理解
2.Code 编写与前端商量好的协议号
package com.itheima.controller;public class Code {public static final Integer SAVE_OK = 20011;public static final Integer DELETE_OK = 20021;public static final Integer UPDATE_OK = 20031;public static final Integer GET_OK = 20041;public static final Integer SAVE_ERR = 20010;public static final Integer DELETE_ERR = 20020;public static final Integer UPDATE_ERR = 20030;public static final Integer GET_ERR = 20040;public static final Integer SYSTEM_ERR = 50001;public static final Integer SYSTEM_TIMEOUT_ERR = 50002;public static final Integer BUSINESS_ERR = 50002;public static final Integer SYSTEM_UNKNOW_ERR = 59999;}
3.异常处理类
package com.itheima.controller;import com.itheima.exception.BusinessException;
import com.itheima.exception.SystemException;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;//声明类是用来做异常处理的
@RestControllerAdvice
public class ProjectExceptionAdvice {@ExceptionHandler(SystemException.class)public Result doSystemException(SystemException ex){//记录日志//发送消息给运维//发送邮件给开发return new Result(ex.getCode() , null ,ex.getMessage());}@ExceptionHandler(BusinessException.class)public Result doBusinessException(BusinessException ex){return new Result(ex.getCode(),null ,ex.getMessage());}//告诉他处理什么异常@ExceptionHandler(Exception.class)public Result doException(Exception ex){System.out.println("Bug ");return new Result(Code.SYSTEM_UNKNOW_ERR,"null" , "系统繁忙,请稍后再试");}}
分为三部分 系统异常 , 运行异常 ,其他异常 根据返回一个异常类 来表明出现什么问题
3.异常类Result
package com.itheima.controller;public class Result {private Object data;private Integer code;private String msg;public Result() {}public Result(Integer code,Object data ) {this.data = data;this.code = code;}public Result(Integer code,Object data, String msg) {this.data = data;this.code = code;this.msg = msg;}public Object getData() {return data;}public void setData(Object data) {this.data = data;}public Integer getCode() {return code;}public void setCode(Integer code) {this.code = code;}public String getMsg() {return msg;}public void setMsg(String msg) {this.msg = msg;}
}
dao层
package com.itheima.dao;import com.itheima.domain.Book;
import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;import java.util.List;/*** 提供怎删改查功能*/
public interface BookDao {// 这里中的type指的是book中属性//使用这个语句可以少写一个数据库操作类@Insert("INSERT INTO tbl_book values (null , #{type}, #{name},#{description}) ")//第二种写法 为了不写id 因为id是默认给的// 下面的type是表中字段名 这里的是Book中的属性//@Insert("INSERT INTO tbl_book(type, name, description) values (#{type}, #{name},#{description}) ")public int save(Book book);@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();}
执行对数据库操作的内容
domain
package com.itheima.domain;public class Book {private Integer id;private String type;private String name;private String description;@Overridepublic String toString() {return "Book{" +"id=" + id +", type='" + type + '\'' +", name='" + name + '\'' +", description='" + description + '\'' +'}';}public int getId() {return id;}public void setId(int id) {this.id = id;}public String getType() {return type;}public void setType(String type) {this.type = type;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getDescription() {return description;}public void setDescription(String description) {this.description = description;}
}
用于映射数据库 在MyBatis配置类中会用到这个类
exception类
两个异常处理相关方法
package com.itheima.exception;public class BusinessException extends RuntimeException{//添加异常编号//添加异常编号private Integer code;public Integer getCode() {return code;}public void setCode(Integer code) {this.code = code;}public BusinessException(String message, Integer code) {super(message);this.code = code;}public BusinessException(String message, Throwable cause, Integer code) {super(message, cause);this.code = code;}public BusinessException(Throwable cause, Integer code) {super(cause);this.code = code;}}
package com.itheima.exception;public class SystemException extends RuntimeException{//添加异常编号private Integer code;public Integer getCode() {return code;}public void setCode(Integer code) {this.code = code;}public SystemException(String message, Integer code) {super(message);this.code = code;}public SystemException(String message, Throwable cause, Integer code) {super(message, cause);this.code = code;}public SystemException(Throwable cause, Integer code) {super(cause);this.code = code;}}
service 包
使用了事务
package com.itheima.service;import com.itheima.domain.Book;
import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;
import org.springframework.transaction.annotation.Transactional;import java.util.List;@Transactional
public interface BookService {/*** 保存* @param book* @return*/boolean save(Book book);/*** 修改* @param book* @return*/boolean update(Book book);/*** 按id删除* @param id* @return*/boolean delete(Integer id);/*** 按id查询* @param id* @return*/Book getById(Integer id);/*** 查询全部* @return*/List<Book> getAll();}
在package com.itheima.service.impl;import com.itheima.controller.Code;
import com.itheima.dao.BookDao;
import com.itheima.domain.Book;
import com.itheima.exception.BusinessException;
import com.itheima.exception.SystemException;
import com.itheima.service.BookService;
import com.itheima.service.BookService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;import java.util.List;@Service
public class BookServiceImpl implements BookService {/*** 进行添加正确失败的判断是根据BookDao传回来的受影响行数决定 >0表示操作成功*/@Autowired//这里通常会报错 不用理会 可以执行private BookDao bookDao;public boolean save(Book book) {;return bookDao.save(book) > 0;}public boolean update(Book book) {return bookDao.update(book) > 0;}public boolean delete(Integer id) {return bookDao.delete(id) >0;}public Book getById(Integer id) {
//
// if (id == 1){
// throw new BusinessException("错误", Code.BUSINESS_ERR);
// }
//
// //将可能出现的异常进行包装,转换为自定义异常
// try {
// // int i = 1/0;
// } catch (Exception e) {
// throw new SystemException("访问超时请重试", e, Code.SYSTEM_TIMEOUT_ERR);
// }return bookDao.getById(id);}public List<Book> getAll() {return bookDao.getAll();}
}
插入代码片
剩下的部分是前端相关在资源中有介绍