有关JSON的工具类

/**

* Copyright (c) linkwise 2007-2009 corporation.

* All rights reserved

*/

package com.linghui.common.util;

import java.util.ArrayList;

import java.util.Date;

import java.util.HashMap;

import java.util.Iterator;

import java.util.List;

import java.util.Map;

import net.sf.json.JSONArray;

import net.sf.json.JSONObject;

import net.sf.json.JsonConfig;

import net.sf.json.util.CycleDetectionStrategy;

import com.linghui.common.util.DateUtil;

import com.linghui.common.util.jsonutil.DateJsonValueProcessor;

/** *//**

* @author </br> <a href="mailto:fx19800215@163.com"> robert.feng</a>

*

*/

public class JsonUtil ...{

/** *//**

* 从一个JSON 对象字符格式中得到一个java对象

* @param jsonString

* @param pojoCalss

* @return

*/

public static Object getObject4JsonString(String jsonString,Class pojoCalss)...{

Object pojo;

JSONObject jsonObject = JSONObject.fromObject( jsonString );

pojo = JSONObject.toBean(jsonObject,pojoCalss);

return pojo;

}

/** *//**

* 从json HASH表达式中获取一个map，改map支持嵌套功能

* @param jsonString

* @return

*/

public static Map getMap4Json(String jsonString)...{

JSONObject jsonObject = JSONObject.fromObject( jsonString );

Iterator keyIter = jsonObject.keys();

String key;

Object value;

Map valueMap = new HashMap();

while( keyIter.hasNext())

...{

key = (String)keyIter.next();

value = jsonObject.get(key);

valueMap.put(key, value);

}

return valueMap;

}

/** *//**

* 从json数组中得到相应java数组

* @param jsonString

* @return

*/

public static Object[] getObjectArray4Json(String jsonString)...{

JSONArray jsonArray = JSONArray.fromObject(jsonString);

return jsonArray.toArray();

}

/** *//**

* 从json对象集合表达式中得到一个java对象列表

* @param jsonString

* @param pojoClass

* @return

*/

public static List getList4Json(String jsonString, Class pojoClass)...{

JSONArray jsonArray = JSONArray.fromObject(jsonString);

JSONObject jsonObject;

Object pojoValue;

List list = new ArrayList();

for ( int i = 0 ; i<jsonArray.size(); i++)...{

jsonObject = jsonArray.getJSONObject(i);

pojoValue = JSONObject.toBean(jsonObject,pojoClass);

list.add(pojoValue);

}

return list;

}

/** *//**

* 从json数组中解析出java字符串数组

* @param jsonString

* @return

*/

public static String[] getStringArray4Json(String jsonString)...{

JSONArray jsonArray = JSONArray.fromObject(jsonString);

String[] stringArray = new String[jsonArray.size()];

for( int i = 0 ; i<jsonArray.size() ; i++ )...{

stringArray[i] = jsonArray.getString(i);

}

return stringArray;

}

/** *//**

* 从json数组中解析出javaLong型对象数组

* @param jsonString

* @return

*/

public static Long[] getLongArray4Json(String jsonString)...{

JSONArray jsonArray = JSONArray.fromObject(jsonString);

Long[] longArray = new Long[jsonArray.size()];

for( int i = 0 ; i<jsonArray.size() ; i++ )...{

longArray[i] = jsonArray.getLong(i);

}

return longArray;

}

/** *//**

* 从json数组中解析出java Integer型对象数组

* @param jsonString

* @return

*/

public static Integer[] getIntegerArray4Json(String jsonString)...{

JSONArray jsonArray = JSONArray.fromObject(jsonString);

Integer[] integerArray = new Integer[jsonArray.size()];

for( int i = 0 ; i<jsonArray.size() ; i++ )...{

integerArray[i] = jsonArray.getInt(i);

}

return integerArray;

}

/** *//**

* 从json数组中解析出java Date 型对象数组，使用本方法必须保证

* @param jsonString

* @return

*/

public static Date[] getDateArray4Json(String jsonString,String DataFormat)...{

JSONArray jsonArray = JSONArray.fromObject(jsonString);

Date[] dateArray = new Date[jsonArray.size()];

String dateString;

Date date;

for( int i = 0 ; i<jsonArray.size() ; i++ )...{

dateString = jsonArray.getString(i);

date = DateUtil.stringToDate(dateString, DataFormat);

dateArray[i] = date;

}

return dateArray;

}

/** *//**

* 从json数组中解析出java Integer型对象数组

* @param jsonString

* @return

*/

public static Double[] getDoubleArray4Json(String jsonString)...{

JSONArray jsonArray = JSONArray.fromObject(jsonString);

Double[] doubleArray = new Double[jsonArray.size()];

for( int i = 0 ; i<jsonArray.size() ; i++ )...{

doubleArray[i] = jsonArray.getDouble(i);

}

return doubleArray;

}

/** *//**

* 将java对象转换成json字符串

* @param javaObj

* @return

*/

public static String getJsonString4JavaPOJO(Object javaObj)...{

JSONObject json;

json = JSONObject.fromObject(javaObj);

return json.toString();

}

/** *//**

* 将java对象转换成json字符串,并设定日期格式

* @param javaObj

* @param dataFormat

* @return

*/

public static String getJsonString4JavaPOJO(Object javaObj , String dataFormat)...{

JSONObject json;

JsonConfig jsonConfig = configJson(dataFormat);

json = JSONObject.fromObject(javaObj,jsonConfig);

return json.toString();

}

/** *//**

* @param args

*/

public static void main(String[] args) ...{

// TODO 自动生成方法存根

}

/** *//**

* JSON 时间解析器具

* @param datePattern

* @return

*/

public static JsonConfig configJson(String datePattern) ...{

JsonConfig jsonConfig = new JsonConfig();

jsonConfig.setExcludes(new String[]...{""});

jsonConfig.setIgnoreDefaultExcludes(false);

jsonConfig.setCycleDetectionStrategy(CycleDetectionStrategy.LENIENT);

jsonConfig.registerJsonValueProcessor(Date.class,

new DateJsonValueProcessor(datePattern));

return jsonConfig;

}

/** *//**

*

* @param excludes

* @param datePattern

* @return

*/

public static JsonConfig configJson(String[] excludes,

String datePattern) ...{

JsonConfig jsonConfig = new JsonConfig();

jsonConfig.setExcludes(excludes);

jsonConfig.setIgnoreDefaultExcludes(false);

jsonConfig.setCycleDetectionStrategy(CycleDetectionStrategy.LENIENT);

jsonConfig.registerJsonValueProcessor(Date.class,

new DateJsonValueProcessor(datePattern));

return jsonConfig;

}

}

Java代码

/** *//**

* linkwise

*/

package com.linghui.common.util.jsonutil;

import java.text.DateFormat;

import java.text.SimpleDateFormat;

import java.util.Date;

import net.sf.json.JsonConfig;

import net.sf.json.processors.JsonValueProcessor;

/** *//**

* @author </br> <a href="mailto:fx19800215@163.com"> robert.feng</a>

*

*/

public class DateJsonValueProcessor implements JsonValueProcessor ...{

public static final String DEFAULT_DATE_PATTERN = "yyyy-MM-dd";

private DateFormat dateFormat;

/** *//**

* 构造方法.

*

* @param datePattern 日期格式

*/

public DateJsonValueProcessor(String datePattern) ...{

if( null == datePattern )

dateFormat = new SimpleDateFormat(DEFAULT_DATE_PATTERN);

else

dateFormat = new SimpleDateFormat(datePattern);

}

/**//* （非 Javadoc）

* @see net.sf.json.processors.JsonValueProcessor#processArrayValue(java.lang.Object, net.sf.json.JsonConfig)

*/

public Object processArrayValue(Object arg0, JsonConfig arg1) ...{

// TODO 自动生成方法存根

return process(arg0);

}

/**//* （非 Javadoc）

* @see net.sf.json.processors.JsonValueProcessor#processObjectValue(java.lang.String, java.lang.Object, net.sf.json.JsonConfig)

*/

public Object processObjectValue(String arg0, Object arg1, JsonConfig arg2) ...{

// TODO 自动生成方法存根

return process(arg1);

}

private Object process(Object value) ...{

return dateFormat.format((Date) value);

}

}