2. 功能模块开发
2.1 数据层开发(BookDao)
Book实体类 public class Book { private Integer id; private String type; private String name; private String description; //自行添加getter、setter、toString()方法 }
BookDao接口
public interface BookDao { @Insert("insert into tbl_book (type,name,description) values(#{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(); }
2.2 业务层开发(BookService/BookServiceImpl)
BookService接口
@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(); }
BookServiceImpl实现类
@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(); } }
2.3 表现层开发(BookController)
@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(); } }
3. 接口测试
3.1 Spring整合Junit测试业务层方法
@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); } }
3.2 postman测试表现层接口
测试保存图书
这里就以保存图书为例,其他接口同样测试
二、表现层数据封装
目前我们表现层响应给客户端的数据有哪几种?
1. 表现层响应数据的问题
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
2. 定义Result类封装响应结果
2.1 Result类封装响应结果
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
2.2 Code类封装响应码
//状态码 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; }
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
3 表现层数据封装返回Result对象
@RestController @RequestMapping("/books") public class BookController { @Autowired private BookService bookService; @PostMapping public Result save(@RequestBody Book book) { boolean flag = bookService.save(book); 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); 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); } @GetMapping public Result getAll() { List<Book> bookList = bookService.getAll(); Integer code = bookList != null ? Code.GET_OK : Code.GET_ERR; String msg = bookList != null ? "" : "数据查询失败,请重试!"; return new Result(code,bookList,msg); } }