前提

AOP，全称是Aspect Oriented Programming，即面向切面编程。AOP的目的是将那些与业务无关，但是业务模块都需要的功能，如日志统计、安全控制、事务处理等，封装成可重用的组件，从而将它们从业务逻辑代码中划分出来，编写成独立的切面。这样做，既可以保持业务逻辑的纯净和高内聚性，又可以使得系统的多个模块都可以共享这些公共的功能。 Spring框架提供了对AOP的支持，Spring Boot自然也不例外。使用Spring Boot的AOP功能，我们可以在运行时动态地将代码横向切入到各个关注点（方法或者类）中。这种横向切面的方式，比传统的纵向切面（继承）更加灵活。

依赖

xml

java

<dependency>

<groupId>org.springframework.boot</groupId>

<artifactId>spring-boot-starter-aop</artifactId>

</dependency>

<dependency>

<groupId>org.mybatis.spring.boot</groupId>

<artifactId>mybatis-spring-boot-starter</artifactId>

</dependency>

拦截器

拦截器常用方法 LogInterceptor.preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)方法：拦截请求并记录日志的方法。 LogInterceptor.getIpAddress(HttpServletRequest request)方法：获取请求的IP地址。 LogInterceptor.getCurrentUsername()方法：获取当前用户。 LogInterceptor.getParams(HttpServletRequest request)方法：获取请求的参数。 LogAspect.logAspect()方法：定义AOP切入点，拦截Controller类中的所有方法。 LogAspect.doBefore(JoinPoint joinPoint)方法：执行方法拦截操作，并调用LogInterceptor.preHandle方法来记录日志。

java

@Component

public class LogInterceptor implements HandlerInterceptor {

@Autowired

private LogRepository logRepository;

@Override

public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {

// 获取请求的IP地址

String ip = getIpAddress(request);

// 获取当前用户

String username = getCurrentUsername();

// 获取请求的方法名

String method = request.getMethod();

// 获取请求的URL

String url = request.getRequestURI();

// 获取请求的参数

String params = getParams(request);

// 创建日志实体

Log log = new Log();

log.setIp(ip);

log.setMethod(method);

log.setOperation("访问");

log.setParams(params);

log.setUsername(username);

log.setCreateTime(new Date());

// 保存日志到数据库中

logRepository.save(log);



return true;

}

// 省略实现HandlerInterceptor接口的其他方法

/**

* 获取请求的IP地址

*/

private String getIpAddress(HttpServletRequest request) {

String ip = request.getHeader("X-Forwarded-For");

if (StringUtils.isBlank(ip) || "unknown".equalsIgnoreCase(ip)) {

ip = request.getHeader("Proxy-Client-IP");

}

if (StringUtils.isBlank(ip) || "unknown".equalsIgnoreCase(ip)) {

ip = request.getHeader("WL-Proxy-Client-IP");

}

if (StringUtils.isBlank(ip) || "unknown".equalsIgnoreCase(ip)) {

ip = request.getHeader("HTTP_CLIENT_IP");

}

if (StringUtils.isBlank(ip) || "unknown".equalsIgnoreCase(ip)) {

ip = request.getHeader("HTTP_X_FORWARDED_FOR");

}

if (StringUtils.isBlank(ip) || "unknown".equalsIgnoreCase(ip)) {

ip = request.getRemoteAddr();

}

return ip;

}

/**

* 获取当前用户

*/

private String getCurrentUsername() {

Authentication authentication = SecurityContextHolder.getContext().getAuthentication();

if (authentication != null) {

return authentication.getName();

}

return null;

}

/**

* 获取请求的参数

*/

private String getParams(HttpServletRequest request) {

Map<String, String[]> parameterMap = request.getParameterMap();

if (parameterMap == null || parameterMap.isEmpty()) {

return null;

}

StringBuilder sb = new StringBuilder();

for (Map.Entry<String, String[]> entry : parameterMap.entrySet()) {

sb.append(entry.getKey()).append("=").append(Arrays.toString(entry.getValue())).append("&");

}

return sb.toString();

}

}

Aspect

java

@Aspect

@Component

public class LogAspect {

@Autowired

private LogInterceptor logInterceptor;

@Pointcut("execution(public * com.example.demo.controller..*.*(..))")

public void logAspect() {}

@Before("logAspect()")

public void doBefore(JoinPoint joinPoint) {

ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();

if (attributes == null) {

return;

}

HttpServletRequest request = attributes.getRequest();

HttpServletResponse response = attributes.getResponse();

HandlerMethod handlerMethod = (HandlerMethod) joinPoint.getSignature();

try {

logInterceptor.preHandle(request, response, handlerMethod);

} catch (Exception e) {

e.printStackTrace();

}

}

}