Spring自定义注解

功能简介

本文主要记录如何使用aop切面的方式来实现日志记录功能。

主要记录的信息有: 操作人，方法名，参数，运行时间，操作类型(增删改查)，详细描述，返回值。

项目结构图

代码实现

1、maven依赖pom.xml

主要是spring-boot-starter-aop的包引入。

<dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- spring-boot aop依赖配置引入 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-aop</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.58</version>
        </dependency>
    </dependencies>

2、AOP切点类

这个是最主要的类,可以使用自定义注解或针对包名实现AOP增强。

1)这里实现了对自定义注解的环绕增强切点，对使用了自定义注解的方法进行AOP切面处理；

2)对方法运行时间进行监控；

3)对方法名，参数名，参数值，对日志描述的优化处理；

在方法上增加@Aspect 注解声明切面,使用@Pointcut 注解定义切点，标记方法。

使用切点增强的时机注解:@Before,@Around,@AfterReturning,@AfterThrowing,@After

@Aspect
@Component
public class LogAspect {

    /**
     * 此处的切点是注解的方式，也可以用包名的方式达到相同的效果
     * '@Pointcut("execution(* com.wwj.springboot.service.impl.*.*(..))")'
     */
    @Pointcut("@annotation(cn.xbmchina.myannotations.annotation.OperationLogDetail)")
    public void operationLog(){}


    /**
     * 环绕增强，相当于MethodInterceptor
     */
    @Around("operationLog()")
    public Object doAround(ProceedingJoinPoint joinPoint) throws Throwable {
        Object res = null;
        long time = System.currentTimeMillis();
        try {
            res =  joinPoint.proceed();
            time = System.currentTimeMillis() - time;
            return res;
        } finally {
            try {
                //方法执行完成后增加日志
                addOperationLog(joinPoint,res,time);
            }catch (Exception e){
                System.out.println("LogAspect 操作失败：" + e.getMessage());
                e.printStackTrace();
            }
        }
    }

    private void addOperationLog(JoinPoint joinPoint, Object res, long time){
        MethodSignature signature = (MethodSignature)joinPoint.getSignature();
        OperationLog operationLog = new OperationLog();
        operationLog.setRunTime(time);
        operationLog.setReturnValue(JSON.toJSONString(res));
        operationLog.setId(UUID.randomUUID().toString());
        operationLog.setArgs(JSON.toJSONString(joinPoint.getArgs()));
        operationLog.setCreateTime(new Date());
        operationLog.setMethod(signature.getDeclaringTypeName() + "." + signature.getName());
        operationLog.setUserId("#{currentUserId}");
        operationLog.setUserName("#{currentUserName}");
        OperationLogDetail annotation = signature.getMethod().getAnnotation(OperationLogDetail.class);
        if(annotation != null){
            operationLog.setLevel(annotation.level());
            operationLog.setDescribe(getDetail(((MethodSignature)joinPoint.getSignature()).getParameterNames(),joinPoint.getArgs(),annotation));
            operationLog.setOperationType(annotation.operationType().getValue());
            operationLog.setOperationUnit(annotation.operationUnit().getValue());
        }
        //TODO 这里保存日志
        System.out.println("记录日志:" + operationLog.toString());
//        operationLogService.insert(operationLog);
    }

    /**
     * 对当前登录用户和占位符处理
     * @param argNames 方法参数名称数组
     * @param args 方法参数数组
     * @param annotation 注解信息
     * @return 返回处理后的描述
     */
    private String getDetail(String[] argNames, Object[] args, OperationLogDetail annotation){

        Map<Object, Object> map = new HashMap<>(4);
        for(int i = 0;i < argNames.length;i++){
            map.put(argNames[i],args[i]);
        }

        String detail = annotation.detail();
        try {
            detail = "'" + "#{currentUserName}" + "'=》" + annotation.detail();
            for (Map.Entry<Object, Object> entry : map.entrySet()) {
                Object k = entry.getKey();
                Object v = entry.getValue();
                detail = detail.replace("{{" + k + "}}", JSON.toJSONString(v));
            }
        }catch (Exception e){
            e.printStackTrace();
        }
        return detail;
    }

    @Before("operationLog()")
    public void doBeforeAdvice(JoinPoint joinPoint){
        System.out.println("进入方法前执行.....");

    }

    /**
     * 处理完请求，返回内容
     * @param ret
     */
    @AfterReturning(returning = "ret", pointcut = "operationLog()")
    public void doAfterReturning(Object ret) {
        System.out.println("方法的返回值 : " + ret);
    }

    /**
     * 后置异常通知
     */
    @AfterThrowing("operationLog()")
    public void throwss(JoinPoint jp){
        System.out.println("方法异常时执行.....");
    }


    /**
     * 后置最终通知,final增强，不管是抛出异常或者正常退出都会执行
     */
    @After("operationLog()")
    public void after(JoinPoint jp){
        System.out.println("方法最后执行.....");
    }

}

3、自定义注解

//@OperationLogDetail(detail = "通过手机号[{{tel}}]获取用户名",level = 3,operationUnit = OperationUnit.USER,operationType = OperationType.SELECT)
@Documented
@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
public @interface OperationLogDetail {

    /**
     * 方法描述,可使用占位符获取参数:{{tel}}
     */
    String detail() default "";

    /**
     * 日志等级:自己定，此处分为1-9
     */
    int level() default 0;

    /**
     * 操作类型(enum):主要是select,insert,update,delete
     */
    OperationType operationType() default OperationType.UNKNOWN;

    /**
     * 被操作的对象(此处使用enum):可以是任何对象，如表名(user)，或者是工具(redis)
     */
    OperationUnit operationUnit() default OperationUnit.UNKNOWN;
}

4、注解用到的枚举类型

OperationType的操作类型

public enum OperationType {
    /**
     * 操作类型
     */
    UNKNOWN("unknown"),
    DELETE("delete"),
    SELECT("select"),
    UPDATE("update"),
    INSERT("insert");

    private String value;

    public String getValue() {
        return value;
    }

    public void setValue(String value) {
        this.value = value;
    }

    OperationType(String s) {
        this.value = s;
    }
}

OperationUnit是被操作的单元

public enum OperationUnit {
    /**
     * 被操作的单元
     */
    UNKNOWN("unknown"),
    USER("user"),
    EMPLOYEE("employee"),
    Redis("redis");

    private String value;

    OperationUnit(String value) {
        this.value = value;
    }

    public String getValue() {
        return value;
    }

    public void setValue(String value) {
        this.value = value;
    }
}

5、日志记录对象

public class OperationLog {

    private String id;
    private Date createTime;
    /**
     * 日志等级
     */
    private Integer level;
    /**
     * 被操作的对象
     */
    private String operationUnit;
    /**
     * 方法名
     */
    private String method;
    /**
     * 参数
     */
    private String args;
    /**
     * 操作人id
     */
    private String userId;
    /**
     * 操作人
     */
    private String userName;
    /**
     * 日志描述
     */
    private String describe;
    /**
     * 操作类型
     */
    private String operationType;
    /**
     * 方法运行时间
     */
    private Long runTime;
    /**
     * 方法返回值
     */
    private String returnValue;

    @Override
    public String toString() {
        return "OperationLog{" +
                "id='" + id + '\'' +
                ", createTime=" + createTime +
                ", level=" + level +
                ", operationUnit='" + operationUnit + '\'' +
                ", method='" + method + '\'' +
                ", args='" + args + '\'' +
                ", userId='" + userId + '\'' +
                ", userName='" + userName + '\'' +
                ", describe='" + describe + '\'' +
                ", operationType='" + operationType + '\'' +
                ", runTime=" + runTime +
                ", returnValue='" + returnValue + '\'' +
                '}';
    }

    public Long getRunTime() {
        return runTime;
    }

    public void setRunTime(Long runTime) {
        this.runTime = runTime;
    }

    public String getReturnValue() {
        return returnValue;
    }

    public void setReturnValue(String returnValue) {
        this.returnValue = returnValue;
    }

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public Date getCreateTime() {
        return createTime;
    }

    public void setCreateTime(Date createTime) {
        this.createTime = createTime;
    }

    public Integer getLevel() {
        return level;
    }

    public void setLevel(Integer level) {
        this.level = level;
    }

    public String getOperationUnit() {
        return operationUnit;
    }

    public void setOperationUnit(String operationUnit) {
        this.operationUnit = operationUnit;
    }

    public String getMethod() {
        return method;
    }

    public void setMethod(String method) {
        this.method = method;
    }

    public String getArgs() {
        return args;
    }

    public void setArgs(String args) {
        this.args = args;
    }

    public String getUserId() {
        return userId;
    }

    public void setUserId(String userId) {
        this.userId = userId;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getDescribe() {
        return describe;
    }

    public void setDescribe(String describe) {
        this.describe = describe;
    }

    public String getOperationType() {
        return operationType;
    }

    public void setOperationType(String operationType) {
        this.operationType = operationType;
    }
}

至此，一个关于日志的自定义注解已经实现了，下面我们就要使用一下该注解在实际中业务代码中。

6、Controller业务控制类

@Controller
@RequestMapping("user")
public class UserController {

    @Autowired
    private UserService userService;

    /**
     * 访问路径 http://localhost:11000/user/findUserNameByTel?tel=1234567
     * @param tel 手机号
     * @return userName
     */
    @ResponseBody
    @RequestMapping("/findUserNameByTel")
    public String findUserNameByTel(@RequestParam("tel") String tel){
        return userService.findUserName(tel);
    }
}

7、服务类Service

public interface UserService {

    /**
     * 获取用户信息
     * @return
     * @param tel
     */
    String findUserName(String tel);
}


@Service
public class UserServiceImpl implements UserService {

    @OperationLogDetail(detail = "通过手机号[{{tel}}]获取用户名",level = 3,operationUnit = OperationUnit.USER,operationType = OperationType.SELECT)
    @Override
    public String findUserName(String tel) {
        System.out.println("tel:" + tel);
        return "zhangsan";
    }
}

8、测试结果

启动项目，在浏览器访问

http://localhost:8080/user/findUserNameByTel?tel=231432535464

最终结果如下图：

总结

自定义注解的步骤：
1、模仿已存在的注解，写一个自定义的注解。
2、使用AOP以该注解为切入点，对其前后等进行切面编程。

最后

如果对 Java、大数据感兴趣请长按二维码关注一波，我会努力带给你们价值。觉得对你哪怕有一丁点帮助的请帮忙点个赞或者转发哦。
关注公众号【爱编码】，小编会一直更新文章的哦。