JsonUtil JSONObject、JavaBean、Model、list相互转化

package com.XXX.XXX.common.util;
//上面是包路径
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.text.SimpleDateFormat;
import java.sql.Date;
import java.sql.Timestamp;

import java.lang.reflect.InvocationTargetException;
import java.math.BigDecimal;
import java.text.ParseException;
import java.util.List;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

public class JsonUtil {
	
	/**
	 * JSONObject对象转JavaBean
	 * @param JSONObject
	 * @param JavaBean的class
	 * @return 转换结果（异常情况下返回null）
	 */
	public static Object jsonToBean(JSONObject json, Class cls)
	{
		Object obj = null;
		
		try
		{
			obj = cls.newInstance();
			
			// 取出Bean里面的所有方法
			Method[] methods = cls.getMethods();
			for(int i=0; i < methods.length; i++)
			{
				// 取出方法名
				String methodName = methods[i].getName();
				// 取出方法的类型
				Class[] clss = methods[i].getParameterTypes();
				if(clss.length != 1)
				{
					continue;
				}
				
				// 若是方法名不是以set开始的则退出本次循环
				if(methodName.indexOf("set") < 0)
				{
					continue;
				}
				
				// 类型
				String type = clss[0].getSimpleName();
				
				String key = methodName.substring(3, 4).toLowerCase() + methodName.substring(4);
				
				// 如果map里有该key
				if(json.has(key) && json.get(key) != null)
				{
					setValue(type, json.get(key), methods[i], obj);
				}
			}
		} catch (Exception ex)
		{
			LogUtil.errorLog(JsonUtil.class, "JSONObject转JavaBean失败", ex);
		}
		
		return obj;
	}
	
	/**
	 * 根据key从JSONObject对象中取得对应值
	 * @param json
	 * @param key
	 * @return
	 * @throws JSONException
	 */
	public static String getString(JSONObject json, String key) throws JSONException
	{
		String retVal = null;
		if(json.isNull(key))
		{
			retVal = "";
		}
		else
		{
			retVal = json.getString(key);
		}
		return retVal;
	}
	
	/**
	 * 给JavaBean的每个属性设值
	 * @param type
	 * @param value
	 * @param method
	 * @param bean
	 * @throws IllegalArgumentException
	 * @throws IllegalAccessException
	 * @throws InvocationTargetException
	 * @throws ParseException
	 */
	private static void setValue(String type, Object value, Method method, Object bean)
	{
		if(value != null && !"".equals(value))
		{
			try
			{
				if("String".equals(type))
				{
					method.invoke(bean, new Object[] {value});
				} else if("int".equals(type) || "Integer".equals(type))
				{
					method.invoke(bean, new Object[] { new Integer(""+value) });
				} else if("double".equals(type) || "Double".equals(type))
				{
					method.invoke(bean, new Object[] { new Double(""+value) });
				} else if("float".equals(type) || "Float".equals(type))
				{
					method.invoke(bean, new Object[] { new Float(""+value) });
				} else if("long".equals(type) || "Long".equals(type))
				{
					method.invoke(bean, new Object[] { new Long(""+value) });
				} else if("int".equals(type) || "Integer".equals(type))
				{
					method.invoke(bean, new Object[] { new Integer(""+value) });
				} else if("boolean".equals(type) || "Boolean".equals(type))
				{
					method.invoke(bean, new Object[] { Boolean.valueOf(""+value) });
				} else if("BigDecimal".equals(type))
				{
					method.invoke(bean, new Object[] { new BigDecimal(""+value) });
				} else if("Date".equals(type))
				{
					Class dateType = method.getParameterTypes()[0];
					if("java.util.Date".equals(dateType.getName()))
					{
						java.util.Date date = null;
						if("String".equals(value.getClass().getSimpleName()))
						{
							String time = String.valueOf(value);
							String format = null;
							if(time.indexOf(":") > 0)
							{
								if(time.indexOf(":") == time.lastIndexOf(":"))
								{
									format = "yyyy-MM-dd H:mm";
								}
								else
								{
									format = "yyyy-MM-dd H:mm:ss";
								}
							}
							else
							{
								format = "yyyy-MM-dd";
							}
							SimpleDateFormat sf = new SimpleDateFormat();
							sf.applyPattern(format);
							date = sf.parse(time);
						}
						else
						{
							date = (java.util.Date) value;
						}
						
						if(date != null)
						{
							method.invoke(bean, new Object[] { date });
						}
					}
					else if("java.sql.Date".equals(dateType.getName()))
					{
						Date date = null;
						if("String".equals(value.getClass().getSimpleName()))
						{
							String time = String.valueOf(value);
							String format = null;
							if(time.indexOf(":") > 0)
							{
								if(time.indexOf(":") == time.lastIndexOf(":"))
								{
									format = "yyyy-MM-dd H:mm";
								}
								else
								{
									format = "yyyy-MM-dd H:mm:ss";
								}
							}
							else
							{
								format = "yyyy-MM-dd";
							}
							SimpleDateFormat sf = new SimpleDateFormat();
							sf.applyPattern(format);
							date = new Date(sf.parse(time).getTime());
						}
						else
						{
							date = (Date) value;
						}
						
						if(date != null)
						{
							method.invoke(bean, new Object[] { date });
						}
					}
				} else if("Timestamp".equals(type))
				{
					Timestamp timestamp = null;
					if("String".equals(value.getClass().getSimpleName()))
					{
						String time = String.valueOf(value);
						String format = null;
						if(time.indexOf(":") > 0)
						{
							if(time.indexOf(":") == time.lastIndexOf(":"))
							{
								format = "yyyy-MM-dd H:mm";
							}
							else
							{
								format = "yyyy-MM-dd H:mm:ss";
							}
						}
						else
						{
							format = "yyyy-MM-dd";
						}
						SimpleDateFormat sf = new SimpleDateFormat();
						sf.applyPattern(format);
						timestamp = new Timestamp(sf.parse(time).getTime());
					}
					else
					{
						timestamp = (Timestamp) value;
					}
					
					if(timestamp != null)
					{
						method.invoke(bean, new Object[] { timestamp });
					}
				} else if("byte[]".equals(type))
				{
					method.invoke(bean, new Object[] { new String(""+value).getBytes() });
				}
			} catch(Exception ex)
			{
				LogUtil.errorLog(JsonUtil.class, "JSONObject赋值给JavaBean失败", ex);
			}
		}
	}
	
	
	/**
	 * 将Model转换成JSONObject
	 */
	@SuppressWarnings("unchecked")
	public static JSONObject coverModelToJSONObject(Object o) throws Exception{
		JSONObject json = new JSONObject();
		Class clazz = o.getClass();
		Field [] fields = clazz.getDeclaredFields();
		for(int i=0; i< fields.length; i++){
            Field f = fields[i];
            json.put(f.getName(), invokeMethod(clazz,f.getName(),o));
        } 
		return json;
	}
	
	
	/**
	 * 将list转换成JSONArray
	 */
	public static JSONArray coverModelToJSONArray(List list) throws Exception{
		JSONArray array = null;
		if(list.isEmpty()){
			return array;
		}
		array = new JSONArray();
		for(Object o : list){
			array.put(coverModelToJSONObject(o));
		}
		return array;
	}
	
	@SuppressWarnings("unchecked")
	private static Object invokeMethod(Class c, String fieldName,Object o){
        String methodName = fieldName.substring(0, 1).toUpperCase()+ fieldName.substring(1);
        Method method = null;
        try {
            method = c.getMethod("get" + methodName);
            return method.invoke(o);
        } 
        catch (Exception e) {
        	LogUtil.errorLog(e);
        	return "";
        } 
	}
	
}