SpringMVC实现RESTful服务

　　　　　　　　　　SpringMVC实现RESTful服务

　　

这里只说service,controller层的代码。Mapper层则直接继承Mapper<T>则可以，记住mybatis-config.xml一定要配置分页插件和mapper类的插件。

　　1.查询所有用户

　　service：

    @Autowired
    private IUserMapper userMapper;

    @Override
    public EasyUIResult getAllUser(Integer page, Integer rows) {
        // TODO Auto-generated method stub

        // 后台帮我们封装了一个page并且直接存到本地线程
        PageHelper.startPage(page, rows);
        Example example = new Example(User.class);
        example.setOrderByClause("updated desc");
        List<User> list = userMapper.selectByExample(example);
        PageInfo<User> pageInfo = new PageInfo<>(list);
        return new EasyUIResult(pageInfo.getTotal(), pageInfo.getList());
    }

　　controller：

    /**
     * 查询所有用户 返回数据类型为：json格式
     * 
     * @param page
     * @param rows
     * @return
     */
    @RequestMapping(value = "list", method = { RequestMethod.POST })
    public @ResponseBody EasyUIResult finAllUser(@RequestParam(value = "page", defaultValue = "1") Integer page,
            @RequestParam(value = "rows", defaultValue = "5") Integer rows) {
        return userService.getAllUser(page, rows);
    }

　　　　2.根据用户id查询用户信息

　　service:

    @Override
    public User queryUserById(Long id) {
        // TODO Auto-generated method stub
        return userMapper.selectByPrimaryKey(id);
    }

　　cotroller:

@Controller
@RequestMapping("user/rest")
public class RestUserController {

    @Autowired
    private IUserService userService;

    /**
     * 根据id查询用户信息
     * 
     * @param id
     * @return
     */
    @RequestMapping(value = "{userId}", method = RequestMethod.GET)
    public ResponseEntity<User> queryUserById(@PathVariable(value = "userId") Long id) {
        try {
            User user = userService.queryUserById(id);
            if (user == null) {
                return ResponseEntity.status(HttpStatus.NOT_FOUND).body(null);
            }
            // return ResponseEntity.ok(user);
        } catch (Exception e) {
            // TODO: handle exception
            e.printStackTrace();
        }
        // return ResponseEntity.status(500).body(null);
        // 系统内部异常
        return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body(null);
    }

　　　　3.添加一个用户

　　service:

@Override
    public Boolean saveUser(User user) {
        // TODO Auto-generated method stub
        return userMapper.insertSelective(user) == 1;
    }

　　controller:

    /**
     * 添加一个用户
     * 
     * @param user
     * @return
     */
    @RequestMapping(method = RequestMethod.POST)
    public ResponseEntity<Void> addUser(User user) {
        try {
            userService.saveUser(user);
            return ResponseEntity.status(HttpStatus.CREATED).build();
            // return ResponseEntity.ok(user);
        } catch (Exception e) {
            // TODO: handle exception
            e.printStackTrace();
        }
        return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).build();
    }

　　4.修改用户

　　service：

@Override
    public boolean updateUsers(User user) {
        // TODO Auto-generated method stub
        // 修改用户所有信息
        // userMapper.updateByPrimaryKey(User);
        // 修改不为空的字段
        // userMapper.updateByPrimaryKeySelective(record);
        return userMapper.updateByPrimaryKey(user) == 1;
    }

　　controller：

    /**
     * 跟新用户
     * 
     * @param user
     * @return
     */
    @RequestMapping(method = RequestMethod.PUT)
    public ResponseEntity<Void> updateUser(User user) {
        try {
            boolean b = userService.updateUsers(user);
            if (b) {
                return ResponseEntity.status(HttpStatus.NO_CONTENT).build();
            }
            // return ResponseEntity.ok(user);
        } catch (Exception e) {
            // TODO: handle exception
            e.printStackTrace();
        }
        return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).build();
    }

　　5.删除

　　service：

    @Override
    public boolean deleteUser(Long id) {
        // TODO Auto-generated method stub
        return userMapper.deleteByPrimaryKey(id) == 1;
    }

　　controller：

    /**
     * 删除一个用户
     * 
     * @param id
     * @return
     */
    @RequestMapping(method = RequestMethod.DELETE)
    public ResponseEntity<Void> deleteUser(@RequestParam(value = "id", defaultValue = "0") Long id) {
        try {
            if (id == 0) {
                return ResponseEntity.status(HttpStatus.BAD_REQUEST).build();
            }
            boolean b = userService.deleteUser(id);
            if (b) {
                return ResponseEntity.status(HttpStatus.NO_CONTENT).build();
            }
            // return ResponseEntity.ok(user);
        } catch (Exception e) {
            // TODO: handle exception
            e.printStackTrace();
        }
        return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).build();
    }

　　delete删除时比较特殊：一定要注意

　

　　

　　进行删除和修改时，要在web.xml中配置过滤器（补充）：

<!-- 
        将POST请求转化为DELETE或者是PUT
        要用_method指定真正的请求参数
     -->
    <filter>
        <filter-name>HiddenHttpMethodFilter</filter-name>
        <filter-class>org.springframework.web.filter.HiddenHttpMethodFilter</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>HiddenHttpMethodFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

<!-- 解决PUT请求无法提交表单数据的问题 -->
    <filter>
        <filter-name>HttpMethodFilter</filter-name>
        <filter-class>org.springframework.web.filter.HttpPutFormContentFilter</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>HttpMethodFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

　　大功告成！！