1.rest风格增删改查及druid数据源的配置及mybatis的配置

@AllArgsConstructor@NoArgsConstructor@Data@Accessors(chain = true)//lombokpublic class Book implements Serializable {    private   Integer  id;    private    String   name;    private    Integer  price;}

public interface BookMapper {    @Select("select isbn id,book_name name,price from books where  isbn=#{id}")    public Book  getBookById(Integer id);    @Update("")    public void updateBook(Book book);    @Delete("delete from books where  isbn=#{id}")    public void deleteBookById(Integer id);    @Insert("insert into  books(isbn,book_name,price)  values(trim(#{id}),trim(#{name}),trim(#{price}))")    @Options(useGeneratedKeys = true)    public void insertBook(Book book);}

@org.springframework.web.bind.annotation.RestControllerpublic class RestController {      @Autowired      private BookMapper  bookMapper;      @GetMapping("/book/{id:\\d+}")      public Book get(@PathVariable Integer id){            return  bookMapper.getBookById(id);      }      @PutMapping("/book")      public Book  put(Book  book){            bookMapper.updateBook(book);            Book bookNew = bookMapper.getBookById(book.getId());            return  bookNew;      }      @DeleteMapping("/book/{id:\\d+}")      public String   post(@PathVariable Integer id){            bookMapper.deleteBookById(id);            return   id+"删除成功";      }      @PostMapping("/book")      public Book  post(Book  book){            bookMapper.insertBook(book);          Book bookNew = bookMapper.getBookById(book.getId());          return  bookNew;      }}

@Configuration@ComponentScan(value = "springmvc.demo")@MapperScan("springmvc.demo.dao")public class MVCConfig  {}

@Configurationpublic class MVCConfigBean {    @ConfigurationProperties(prefix ="spring.datasource")    @Bean    public DataSource  getDataSource(){        return new DruidDataSource();    }    //配置druid监控页面    @Bean    //添加servlet    public ServletRegistrationBean   statViewServlet(){        ServletRegistrationBean
     
       servlet = new ServletRegistrationBean<>(new StatViewServlet(), "/druid/*");        HashMap
      
        map = new HashMap<>();        map.put("loginUsername", "admin");//账户        map.put("loginPassword", "123456");//密码        map.put("allow", "");//允许所以用户登录,默认允许所有用户登录        map.put("deny", "");//拒绝用户登录，可以是ip地址等        servlet.setInitParameters(map);        return  servlet;    }    @Bean    //添加过滤器    public  FilterRegistrationBean  webStatFilter(){//假如拦截所有那么与标注@component注解作用一样，其他的也是        FilterRegistrationBean
       
         filter = new FilterRegistrationBean<>();        filter.setFilter(new WebStatFilter());        HashMap
        
          map = new HashMap<>();        map.put("exclusions", "*.js,*.css,*/druid/*,*.gif,*.jpg,*.png,*.ico");        filter.setInitParameters(map);        filter.setUrlPatterns(Arrays.asList("/*"));        return filter;    }    //添加配置mybatis的配置    @Bean    public  ConfigurationCustomizer  configurationCustomizer(){        ConfigurationCustomizer configurationCustomizer = x->{            //设置驼峰命名法            x.setMapUnderscoreToCamelCase(true);        };        return configurationCustomizer;    }}
        
       
      
     

#编码处理spring.http.encoding.charset=UTF-8spring.http.encoding.force=truespring.http.encoding.enabled=trueserver.tomcat.uri-encoding=UTF-8#日志logging.level.springmvc.demo.mvcdemo=debug#与mysql数据库连接spring.datasource.driver-class-name=com.mysql.jdbc.Driverspring.datasource.url=jdbc:mysql://localhost:3306/book?useUnicode=true&characterEncoding=utf-8&serverTimezone=GMT%2B8&useSSL=false&verifyServerCertificate=falsespring.datasource.username=rootspring.datasource.password=cgz12345678#使用druid连接池spring.datasource.type=com.alibaba.druid.pool.DruidDataSource#druid连接池连接池参数配置#初始化时建立物理连接的个数。初始化发生在显示调用init方法，或者第一次getConnection时spring.datasource.initialSize=5#最大连接池数量spring.datasource.maxActive=10#获取连接时最大等待时间spring.datasource.maxWait=3000#最小连接池数量spring.datasource.minIdle=3# 配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位是毫秒spring.datasource.timeBetweenEvictionRunsMillis=60000# 配置一个连接在池中最小生存的时间，单位是毫秒spring.datasource.minEvictableIdleTimeMillis=300000#验证数据库连接的有效性spring.datasource.validationQuery=SELECT 1 FROM DUALspring.datasource.testWhileIdle=truespring.datasource.testOnBorrow=falsespring.datasource.testOnReturn=falsespring.datasource.poolPreparedStatements=truespring.datasource.maxPoolPreparedStatementPerConnectionSize=20#stat功能（监控）、wall功能（sql防火墙）、logback功能（监控日志输出）,需要配置添加相应的配置文件否则会报错spring.datasource.filters=stat,wall,logback# 通过connectProperties属性来打开mergeSql功能；慢SQL记录spring.datasource.connectionProperties=druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000

@RunWith(SpringRunner.class)@SpringBootTestpublic class MvcDemoApplicationTests {    @Autowired    WebApplicationContext context;    MockMvc mockMvc;    Logger  logger;    @Before    public void init() {        mockMvc = MockMvcBuilders.webAppContextSetup(context).build();        logger=LoggerFactory.getLogger(MvcDemoApplicationTests.class);    }    @Test    public void testGet() throws Exception {        String contentAsString = mockMvc.perform(MockMvcRequestBuilders.get("/book/1001")                .contentType(MediaType.APPLICATION_JSON_UTF8)).andReturn()                .getResponse().getContentAsString();        logger.debug(contentAsString);        System.out.println(contentAsString);    }    @Test    public void testInsert() throws Exception {        String contentAsString = mockMvc.perform(MockMvcRequestBuilders.post("/book")                .param("name", "     dokcer  ")                .param("price", "150")                .contentType(MediaType.APPLICATION_JSON_UTF8))                .andReturn().getResponse().getContentAsString();        System.out.println(contentAsString);    }    @Test    public  void   testDelete() throws Exception {        String contentAsString = mockMvc.perform(MockMvcRequestBuilders.delete("/book/1003")                .contentType(MediaType.APPLICATION_JSON_UTF8)).andReturn()                .getResponse().getContentAsString();        System.out.println(contentAsString);    }    @Test    public  void  testUpdate() throws Exception {        String contentAsString = mockMvc.perform(MockMvcRequestBuilders.put("/book")                .param("id","1009")                .param("price", "1500")                .contentType(MediaType.APPLICATION_JSON_UTF8))                .andReturn().getResponse().getContentAsString();        System.out.println(contentAsString);    }}

 检查数据源是否配置成功

 

 druid监控页面

2.@Pathvariable注解

2.1配置正则实例

@AllArgsConstructor@NoArgsConstructor@Data@Accessors(chain = true)  //lombokpublic class User implements Serializable {    private  String  name;}

@RestController   //responsebody +controllerpublic class UserController {    @GetMapping("/user/{name:.*}")       public User  testUser(@PathVariable(required = false,value = "name") User user){        System.out.println(user.getClass());        return  user;    }}

@SpringBootApplicationpublic class MvcDemoApplication  {    public static void main(String[] args) {        SpringApplication.run(MvcDemoApplication.class, args);    }}

@Configuration@ComponentScan(value = "springmvc.demo")//扫描包public class MVCConfig  {}

spring.http.encoding.charset=UTF-8 spring.http.encoding.force=truespring.http.encoding.enabled=trueserver.tomcat.uri-encoding=UTF-8

 

3.@valid与@Validated

@valid与@Validated的区别，@Validated是spring中的，是在@valid基础上而来的，在@valid的基础上增加分组功能，这里就直接说@Validated，没有加分组都需要认证，加了分组只有符合分组的才需要认证，一般不使用分组

3.1基本使用

@AllArgsConstructor@NoArgsConstructor@Data@Accessors(chain = true)public class User implements Serializable {    @NotNull(message="不能为空")//含有属性groups    private  String  name;}

@RestControllerpublic class UserController {    @GetMapping("/user")    public User  testUser(@Validated User user, BindingResult  result){        result.getAllErrors().stream().forEach((x)->{            System.out.println(x.getObjectName()+":"+x.getDefaultMessage());        });        return  user;    }}

输出结果：user:不能为空

备注：假如没有BindingResult result，那么在进入testUser之前就会被拦截，message="不能为空"并没有什么作用，加入BindingResult result之后，才会进入testUser方法，在没有进入方法时的异常页面见后该篇4

3.2自定义符合valid的注解

这里定义的是@NoNull注解

//会自动加载，不需要其他的配置public class MyValidAnnotation implements ConstraintValidator
     
       {    /*    obj:需要验证的参数     */    @Override    public boolean isValid(Object obj, ConstraintValidatorContext constraintValidatorContext) {        System.out.println(obj);        return false;    }    @Override    public void initialize(MyNotNull constraintAnnotation) {    }}
     

@Target({ElementType.METHOD, ElementType.FIELD})@Retention(RetentionPolicy.RUNTIME)@Constraint(validatedBy =MyValidAnnotation.class )//添加在@validated的必要注解public @interface MyNotNull {    String message() default "{javax.validation.constraints.NotNull.message}";    Class
     [] groups() default {};    Class
     [] payload() default {};}

@AllArgsConstructor@NoArgsConstructor@Data@Accessors(chain = true)public class User implements Serializable {    @MyNotNull(message="不能为空---MyNotNull")    private  String  name;}

@RestControllerpublic class UserController {    @GetMapping("/user")    public User  testUser(@Validated User user, BindingResult  result){        result.getAllErrors().stream().forEach((x)->{            System.out.println(x.getObjectName()+":"+x.getDefaultMessage());        });        return  user;    }}

4.异常消息的处理

4.1验证异常消息的处理上述已经说明

4.2直接被拦截的异常处理

 

springboot会相应的转向我们在resources下新建的resources的error的相应的错误代码的页面

还可以是如下这样，表示以4开头的错误页面，例如

4.3运行过程中出现的异常

4.3.1直接抛出异常

@GetMapping("/user/error")    public User  testUser1(@Validated User user, BindingResult  result) throws Exception {        throw  new Exception("出错了");    }

 

4.3.2 throw自定义异常类

@ResponseStatus(value = HttpStatus.INTERNAL_SERVER_ERROR,reason = "内部出错了！")public class MyException extends RuntimeException {}

@GetMapping("/user/error")    public User  testUser1(@Validated User user, BindingResult  result) throws Exception {        throw  new MyException();    }

 

4.3.3 使用@ExceptionHandler注解

@ResponseBody    @GetMapping("/testExceptionHandler")    public User  testUser1(@Validated User user, BindingResult  result) throws Exception {        int  i=10/0;        return user;    }

@ExceptionHandler({Exception.class})    public String  testExceptionHandler(){        return   "redirect:/error.html"; //重定向，/站点目录    }

 4.3.4 修改状态码及原因，@ResponseStatus也能在

　　 @ExceptionHandler({Exception.class})    @ResponseStatus(value = HttpStatus.INTERNAL_SERVER_ERROR,reason = "内部错误")    public void  testExceptionHandler(){    }

 备注：这样之后不会去相应的页面，也就是加入有返回值例如return "redirect:/error.html";，会失效

4.3.5@ControllerAdvice定制全局的异常，类中的@ExceptionHandler优先级高于@ControllerAdvice中的@ExceptionHandler优先级

@ControllerAdvicepublic class MyExceptionHandler {    @ExceptionHandler({Exception.class})    @ResponseStatus(value = HttpStatus.INTERNAL_SERVER_ERROR,reason = "内部错误")    public void  testExceptionHandler(){    }}

5.jsonview

@NoArgsConstructor@AllArgsConstructor@Data@Accessors(chain = true)public class User implements Serializable {    public   interface  UserSimpleView{} ;    public   interface  UserDetailView  extends UserSimpleView{} ;   @JsonView(UserSimpleView.class)    private  String username;   @JsonView(UserDetailView.class)    private   Integer password;}

@RestControllerpublic class UserController {    @Autowired    UserMapper userMapper;    @GetMapping("/user/{username}")    @JsonView(User.UserSimpleView.class)    public  User   testGet(@PathVariable String  username){        User user = userMapper.getUserById(username);        return user;    }}

 

6.异步

6.1直接使用callable

@RestControllerpublic class AsyncController {    @Autowired    UserMapper  userMapper;    @GetMapping("/async/{username}")    @JsonView(User.UserSimpleView.class)    public  Callable
     
         get(@PathVariable  String  username){        long id = Thread.currentThread().getId();       long  start= Instant.now().atZone(ZoneId.of("Asia/Shanghai")).toInstant().toEpochMilli();        Callable
      
        callable = ()->{            long id1 = Thread.currentThread().getId();            long  start1= Instant.now().atZone(ZoneId.of("Asia/Shanghai")).toInstant().toEpochMilli();            User user = userMapper.getUserById(username);            long  end1= Instant.now().atZone(ZoneId.of("Asia/Shanghai")).toInstant().toEpochMilli();            System.out.println("副线程"+id1+":"+(end1-start1));            return  user;        };        long  end= Instant.now().atZone(ZoneId.of("Asia/Shanghai")).toInstant().toEpochMilli();        System.out.println("主线程"+id+":"+(end-start));        return  callable;    }}
      
     

 

6.2 使用DeferredResult实现异步

@Bean("queue")    public ConcurrentLinkedQueue
     
         concurrentLinkedQueue() throws IOException {        ConcurrentLinkedQueue
      
        queue = new ConcurrentLinkedQueue<>();        return queue;    }    @Bean("map")    public Map
       
        >   map(){        return  new HashMap();    }
       
      
     

@Autowired    ConcurrentLinkedQueue
     
        queue;@Autowired    Map  map; @GetMapping("/async/deferredResult")    public Object  message(@RequestParam(required = false) String message){        if(StringUtils.isNotBlank(message)){            queue.add(message);            DeferredResult
      
        result = new DeferredResult<>();            map.put(message, result);            return result;        }        return "输入格式不正确";    }
      
     

@Componentpublic class QueueListener implements ApplicationListener {//启动监听器    @Autowired    ConcurrentLinkedQueue
     
        queue;    @Autowired    Map
      
       > map;    @Override    public void onApplicationEvent(ApplicationEvent applicationEvent) {        new Thread(()->{            while (true){                try {                    Thread.sleep(3000);                } catch (InterruptedException e) {                    e.printStackTrace();                }                if(queue.size()>0){                    String msg = queue.poll();                    System.out.println(msg);                    map.get(msg).setResult(msg);                    map.remove(msg);                }else {                    try {                        Thread.sleep(10000);                    } catch (InterruptedException e) {                        e.printStackTrace();                    }                }            }        }).start();    }}
      
     

 7.swagger

依赖

         
      
       io.springfox
          
      
       springfox-swagger-ui
          
      
       2.9.2
      
      
                 
      
       io.springfox
                  
      
       springfox-swagger2
                  
      
       2.9.2
      
     

添加注解

@EnableSwagger2public class ControllerTest {

访问页面

http://127.0.0.1:8080/swagger-ui.html

 

增加描述信息

public class Book implements Serializable {    private   Integer  id;    @ApiModelProperty("名称")    private    String   name;    @ApiModelProperty("价格")    private    Integer  price;}

@GetMapping("/book/{id:\\d+}")      public Book get(@PathVariable @ApiParam("书本id") Integer id){            return  bookMapper.getBookById(id);      }

 

8.拦截器

8.1 HandlerInterceptor

@Componentpublic class MyHandlerIntercepter implements HandlerInterceptor {    //在调用目标方法之前执行    @Override    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {        return true;//false表示后续拦截器不在执行    }    //在调用目标方法之后, 但渲染视图之前，    // 可以对请求域中的属性或视图做出修改.，出现异常不会执行该方法    @Override    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {       //能获取类名，方法名，但是不能获取方法的参数        System.out.println(((HandlerMethod)handler).getBean().getClass().getName());        System.out.println(((HandlerMethod)handler).getMethod().getName());    }    //之后执行，出现异常也会执行    @Override    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {    }}

@Configuration@ComponentScan(value = "springmvc.demo")@MapperScan("springmvc.demo.dao")public class MVCConfig implements WebMvcConfigurer {    @Autowired    MyHandlerIntercepter myHandlerIntercepter;    @Override    public void addInterceptors(InterceptorRegistry registry) {        registry.addInterceptor(myHandlerIntercepter);    }}

 8.2 AOP（拦截的增强版）

                 
      
       org.springframework.boot
                  
      
       spring-boot-starter-aop
       
     

@Aspect@Componentpublic class MyAOP {    @Pointcut("execution(* springmvc.demo.controller..*(*))")    public  void pointcut(){}    @Around("pointcut()")    public  Object before(ProceedingJoinPoint joinPoint)  {        try {            Object[] args = joinPoint.getArgs();            Arrays.stream(args).forEach(System.out::println);            Object proceed = joinPoint.proceed();//相当于拦截器的dochain方法，否则不会执行下去            return proceed;//返回结果后才会有值        } catch (Throwable throwable) {            return throwable.getMessage();        }    }}