英文原文：Using AspectJ to log all methods parameters and return values during application runtime 使用如下的 aspect 工具类：

package com.myapp.util;

import java.lang.reflect.Field;
import java.util.List;

import org.apache.log4j.Logger;

public final class AspectUtils {

	private static final Logger logger = Logger.getLogger(AspectUtils.class);

	private AspectUtils() {

	}

	public static Logger getLogger(org.aspectj.lang.JoinPoint joinPoint) {
		try {
			@SuppressWarnings("rawtypes")
			Class declaringType = joinPoint.getSignature().getDeclaringType();
			Field loggerField = declaringType.getDeclaredField("logger");
			loggerField.setAccessible(true);
			return (Logger) loggerField.get(null);
		} catch (NoSuchFieldException e) {

		} catch (Exception e) {

		}
		return logger;
	}

	public static void logParamValues(StringBuilder logLine,
			String[] paramNames, Object[] paramValues) {
		for (int i = 0; i < paramValues.length; i++) {
			logLine.append(paramNames[i]).append("=")
					.append(toString(paramValues[i]));
			if (i < paramValues.length - 1)
				logLine.append(", ");
		}
	}

	@SuppressWarnings("rawtypes")
	public static String toString(Object object) {
		if (object == null)
			return "<null>";
		else if (object instanceof String) {
			if(((String) object).length() > 100)
				return ((String) object).substring(0, 100) + "...[more]";
			else return (String) object;
		}
		else if (object instanceof Long)
			return ((Long) object).toString();
		else if (object instanceof Boolean)
			return ((Boolean) object).toString();
		else if (object instanceof Double)
			return ((Double) object).toString();
		else if (object instanceof Integer)
			return ((Integer) object).toString();
		else if (object instanceof List)
			return "items{" + ((List) object).size() + "}";
		else
			return "object";
	}
}

这个工具类包含三个方法，getLogger 返回 logger 属性。
第二个方法 “logParamValues” 对日志进行格式化处理，格式为：“methodName(param1=xxxx, param2=xxxx)”
第三个方法是 “toString” 用来将对象变成字符串，但内容跟原本的 toString 不同。

使用如下枚举类型来防止对某些特定方法进行记录，可直接使用 @NO_LOG 来忽略方法：

package com.myapp.util;

public @interface NO_LOG {

}

下面就是 aspect 文件，别忘了在你类路径中配置 AspectJ：

import java.util.List;

import org.aspectj.lang.reflect.CodeSignature;

import com.myapp.util.AspectUtils;;

public aspect ServicesLogger {

	pointcut logMethod(): 
		execution(!@com.myapp.util.NO_LOG *  com.myapp.services..* (..));

	before(): logMethod() {
		Object[] paramValues = thisJoinPoint.getArgs();
		String[] paramNames = ((CodeSignature) thisJoinPointStaticPart
				.getSignature()).getParameterNames();
		StringBuilder logLine = new StringBuilder(thisJoinPointStaticPart
				.getSignature().getName()).append("(");
		if (paramNames.length != 0)
			AspectUtils.logParamValues(logLine, paramNames, paramValues);
		logLine.append(") - started");
		AspectUtils.getLogger(thisJoinPoint).info(logLine.toString());
	}

	@SuppressWarnings("rawtypes")
	after() returning(Object r): logMethod(){

		if (r != null && (!(r instanceof List) || ((List) r).size() != 0)) {
			StringBuilder rv = new StringBuilder("Return Value : ");
			rv.append(AspectUtils.toString(r));
			AspectUtils.getLogger(thisJoinPoint).info(rv.toString());
		}

		Object[] paramValues = thisJoinPoint.getArgs();
		String[] paramNames = ((CodeSignature) thisJoinPointStaticPart
				.getSignature()).getParameterNames();
		StringBuilder logLine = new StringBuilder(thisJoinPointStaticPart
				.getSignature().getName()).append("(");
		if (paramNames.length != 0)
			AspectUtils.logParamValues(logLine, paramNames, paramValues);
		logLine.append(") - finished");
		AspectUtils.getLogger(thisJoinPoint).info(logLine.toString());
	}
}

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