JAVA反射相关

1、通过反射获取到类中的所有属性列表

Class cla = entityName.getClass();
Field field[] = cla.getDeclaredFields();

2、获取对象类型的值

public static Object getProperty(Object entityName) throws Exception { 
        for (int i = 0; i < field.length; i++) {
            Field f = field[i];
            if(f.getName().indexOf("Service") > 0){
                f.setAccessible(true);//设置允许访问，不设置的话，属性值为private等就不能获取到值
                return f.get(entityName);//这里返回的是一个service对象,接受到后就能调用里面的方法
            }
        }
}

package com.mobile.core;

import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Enumeration;
import java.util.Map;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.AfterReturning;
import org.aspectj.lang.annotation.AfterThrowing;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;

import com.doone.mobile.controller.WebContextUtils;
import com.doone.mobile.service.base.BaseService;
import com.doone.mobile.tools.UtilString;

/** 
 *  根日志轨迹.
 *  通过AOP能力，将所有方法调用情况输入到根日志器.
 *  输出到控制台.
 * @ClassName: RootLogTrack
 */
@Component
@Aspect
public class RootLogTrack {

    @Resource
    private WebContextUtils webContextUtils;
    
	/**
	 * 
	 * 配置外部接口层切入点.
	 * 切入点匹配表达式com.doone.mobile.controller..*
	 * 匹配包名为com.doone.mobile.controller及子包
	 */
	@Pointcut("within(com.doone.mobile.controller..*)")
	public void controllerPointcut() {
	}
	
	/**
     * 
     * TODO(配置外部接口层切入点.
     * 切入点匹配表达式com.doone.mobile.controller..*
     * 匹配包名为com.doone.mobile.controller及子包).
     * @author Johnny_L_Q
     */
    @Pointcut(value = "execution(* com.doone.mobile.controller..*.save*(..))")
    public void controllerSavePointcut(){}
    
    /**
     * 
     * TODO(配置外部接口层切入点.
     * 切入点匹配表达式com.doone.mobile.controller..*
     * 匹配包名为com.doone.mobile.controller及子包).
     * @author Johnny_L_Q
     */
    @Pointcut(value = "execution(* com.doone.mobile.controller..*.delete*(..))")
    public void controllerDeletePointcut(){}

	/**
	 * 
	 * 方法调用前通过日志纪录类名，方法名和参数值.
	 * @param jp JoinPoint
	 */
	@Before("controllerPointcut()")
	public void methodInvokedBefore(JoinPoint jp) {
		Logger logger = LoggerFactory.getLogger(jp.getTarget().getClass());
		logger.info(jp.toString());
		StringBuilder builder = new StringBuilder();
		Object[] args = jp.getArgs();
		if (args.length > 0) {
			builder.append("arguments:");
		}
		for (Object arg : args) {
			builder.append(arg).append(",");
		}
		if (args.length > 0) {
			builder.deleteCharAt(builder.length() - 1);
		}
		logger.info(builder.toString());
	}
	
	/**
     * 
     * controller中save方法调用前通过日志纪录类名，方法名和参数值.
     * @param jp JoinPoint
     * @author Johnny_L_Q
     */
    @Before("controllerSavePointcut()")
    public void saveMethodInvokedBefore(JoinPoint jp) {
        Logger logger = LoggerFactory.getLogger(jp.getTarget().getClass());
        StringBuilder builder = new StringBuilder();
        builder.append("用户：" + webContextUtils.getUser().getUserName() + ",在时间：" + new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date()) + ",对类" + jp.toString() + ",进行了保存操作,具体参数如下:");
        Object[] args = jp.getArgs();
        if (args.length > 0) {
            if(args[0] instanceof HttpServletRequest){
                HttpServletRequest request = (HttpServletRequest) args[0];
                Enumeration<String> obj = request.getParameterNames();
                Map<String,Object> map = request.getParameterMap();
                //循环遍历所有参数值，并记录到日志中
                while (obj.hasMoreElements()) {
                    String key = (String) obj.nextElement();
                    Object object = ((String[])map.get(key))[0];
                    String value = null;
                    if(object instanceof Long){
                        System.out.println("Long");
                        value = ((Long) object).toString();
                    }else if(object instanceof Integer){
                        System.out.println("Integer");
                        value = ((Integer) object).toString();
                    }else if(object instanceof String){
                        System.out.println("String");
                        value = (String) object;
                    }
                    builder.append("'" + key).append("':").append("'" + value).append("',");
                }
            }else{
                for (Object arg : args) {
                    builder.append(arg).append(",");
                }
            }
        }
        
        if (args.length > 0) {
            builder.deleteCharAt(builder.length() - 1);
        }
        logger.info(builder.toString());
    }
    
    /**
     * 
     * TODO(controller执行删除前获取即将删除的id值).
     * @param request
     * @author Johnny_L_Q
     * @return
     */
    public String getRequestId(HttpServletRequest request){
        Enumeration<String> obj = request.getParameterNames();
        Map<String,Object> map = request.getParameterMap();
        while (obj.hasMoreElements()) {
            String key = (String) obj.nextElement();
            //判断字段名中是否含有Id或者是id，如果有则返回该值
            if(key.indexOf("id") > 0 || key.indexOf("Id") > 0){
                Object object = ((String[])map.get(key))[0];
                String value = null;
                if(object instanceof Long){
                    value = ((Long) object).toString();
                }else if(object instanceof Integer){
                    value = ((Integer) object).toString();
                }else if(object instanceof String){
                    value = (String) object;
                }
                return value;
            }
        }
        return null;
    }
    
    /**
     * 
     * 方法调用前通过日志纪录类名，方法名和参数值.
     * @param jp JoinPoint
     * @author Johnny_L_Q
     */
    @Before("controllerDeletePointcut()")
    public void deleteMethodInvokedBefore(JoinPoint jp) {
        Logger logger = LoggerFactory.getLogger(jp.getTarget().getClass());
        StringBuilder builder = new StringBuilder();
        builder.append("用户：" + webContextUtils.getUser().getUserName() + ",在时间：" + new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date()) + ",对" + jp.toString() + ",进行了删除操作,删除的数据内容如下:");
        Object[] args = jp.getArgs();
        try {
            if (args.length > 0) {
                //获得类中的service属性值
                BaseService service = (BaseService) getProperty(jp.getTarget());
                String id = null;
                if(args[0] instanceof HttpServletRequest){
                    HttpServletRequest request = (HttpServletRequest) args[0];
                    //获取参数ID
                    id = getRequestId(request);
                }
                
                if(!UtilString.isEmpty(id) && null != service){
                    //查询出即将删除的实体
                    Object obj = service.findEntityById(Long.parseLong(id));
                    builder.append(obj.toString());
                }else{
                    System.out.println("id is null");
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        logger.info(builder.toString());
    }
    
    
    /** 
     * 获得一个对象各个属性的字节流 
     */  
    @SuppressWarnings("unchecked")  
    public static Object getProperty(Object entityName) throws Exception {  
        Class c = entityName.getClass();
        Field field[] = c.getDeclaredFields(); 
        for (int i = 0; i < field.length; i++) {
            Field f = field[i];
            if(f.getName().indexOf("Service") > 0){
                f.setAccessible(true);
                return f.get(entityName);
            }
            //System.out.println("---------- " + f.getName() + "\t" + "=========" + "\t" + f.getType());  
        }
        return null;
    }
    

	/**
	 * 
	 * 方法调用后通过日志纪录返回值.
	 * @param jp JoinPoint
	 * @param retVal 返回值
	 */
	@AfterReturning(pointcut = "controllerPointcut()", returning = "retVal")
	public void methodInvokedAfter(JoinPoint jp, Object retVal) {
		Logger logger = LoggerFactory.getLogger(jp.getTarget().getClass());
		StringBuilder builder = new StringBuilder();
		builder.append("return:");
		builder.append(retVal);
		logger.info(builder.toString());
	}

	/**
	 * 
	 * 方法调用产生异常时，通过日志纪录异常.
	 * @param jp JoinPoint
	 * @param ex Exception
	 */
	@AfterThrowing(pointcut = "controllerPointcut()", throwing = "ex")
	public void methodInvokedThrowException(JoinPoint jp, Exception ex) {
		Logger logger = LoggerFactory.getLogger(jp.getTarget().getClass());
		StringBuilder builder = new StringBuilder();
		builder.append("exception:");
		builder.append(ex.getClass().getSimpleName());
		builder.append(ex.getMessage());
		logger.error(builder.toString());
	}

}