經常會用到JSON格式才處理,尤其是在Http請求的時候,網上可以找到很多json處理的相關工具,如org.json和json-lib,下面兩段源代碼是分別使用這兩個工具解析和構造JSON的演示程序。 //這是使用json-lib的程序: import JAVA.util.HashMap; import JAVA.util.Map; import net.sf.json.JSONObject; public class Test { public static void main(String[] args) { String json = "{\"name\":\"reiz\"}"; JSONObject jsonObj = JSONObject.fromObject(json); String name = jsonObj.getString("name"); jsonObj.put("inITial", name.substring(0, 1).toUpperCASE()); String[] likes = new String[] { "JAVAScript", "Skiing", "Apple Pie" }; jsonObj.put("likes", likes); Map <String, String> ingredients = new HashMap <String, String>(); ingredients.put("apples", "3kg"); ingredients.put("sugar", "1kg"); ingredients.put("pastry", "2.4kg"); ingredients.put("bestEaten", "outdoors"); jsonObj.put("ingredients",ingredients); System.out.println(jsonObj); } } //這是使用org.json的程序: import JAVA.util.HashMap; import JAVA.util.Map; import org.json.JSONException; import org.json.JSONObject; public class Test { public static void main(String[] args) throws JSONException { String json = "{\"name\":\"reiz\"}"; JSONObject jsonObj = new JSONObject(json); String name = jsonObj.getString("name"); jsonObj.put("inITial", name.substring(0, 1).toUpperCASE()); String[] likes = new String[] { "JAVAScript", "Skiing", "Apple Pie" }; jsonObj.put("likes", likes); Map <String, String> ingredients = new HashMap <String, String>(); ingredients.put("apples", "3kg"); ingredients.put("sugar", "1kg"); ingredients.put("pastry", "2.4kg"); ingredients.put("bestEaten", "outdoors"); jsonObj.put("ingredients", ingredients); System.out.println(jsonObj); System.out.println(jsonObj); } } //兩者在生成json的時候幾乎是相同的,但org.json比json-lib要輕量得多,前者沒有任何依賴,而后者要依賴ezmorph和commons的lang、logging、beanutils、collections等組件。 但是往往使用的時候,我們會操作Bean和Json的轉換,org.json可以從Bean轉到json,似乎不能從json轉到Bean。下面是我找的幾個例子。
public class JsonUtil { public static Object getObject4JsonString(String jsonString, Class pojoCalss) { Object pojo; JSONObject jsonObject = JSONObject.fromObject(jsonString); pojo = JSONObject.toBean(jsonObject, pojoCalss); return pojo; } 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; } public static Object[] getObjectArray4Json(String jsonString) { JSONArray jsonArray = JSONArray.fromObject(jsonString); return jsonArray.toArray(); } 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; } 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; } 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; } 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; } public static Date[] getDateArray4Json(String jsonString, String DataFormat) throws ParseException { 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.parseDate(dateString, DataFormat); dateArray[i] = date; } return dateArray; } 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; } public static String getJsonString4JavaPOJO(Object javaObj) { JSONObject json; json = JSONObject.fromObject(javaObj); return json.toString(); } public static String getJsonString4JavaPOJO(Object javaObj, String dataFormat) { JSONObject json; JsonConfig jsonConfig = configJson(dataFormat); json = JSONObject.fromObject(javaObj, jsonConfig); return json.toString(); } 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 JsonDateValueProcessor(datePattern)); return jsonConfig; } public static JsonConfig configJson(String[] excludes, String datePattern) { JsonConfig jsonConfig = new JsonConfig(); jsonConfig.setExcludes(excludes); jsonConfig.setIgnoreDefaultExcludes(true); jsonConfig.setCycleDetectionStrategy(CycleDetectionStrategy.LENIENT); jsonConfig.registerJsonValueProcessor(Date.class, new JsonDateValueProcessor(datePattern)); return jsonConfig; } } package com.baiyyy.polabs.util.json; import java.text.SimpleDateFormat; import java.util.Date; import net.sf.json.JsonConfig; import net.sf.json.processors.JsonValueProcessor; public class JsonDateValueProcessor implements JsonValueProcessor { private String format = "yyyy-MM-dd HH:mm:ss"; public JsonDateValueProcessor() { } public JsonDateValueProcessor(String format) { this.format = format; } public Object processArrayValue(Object value, JsonConfig jsonConfig) { String[] obj = {}; if (value instanceof Date[]) { SimpleDateFormat sf = new SimpleDateFormat(format); Date[] dates = (Date[]) value; obj = new String[dates.length]; for (int i = 0; i < dates.length; i++) { obj[i] = sf.format(dates[i]); } } return obj; } public Object processObjectValue(String key, Object value, JsonConfig jsonConfig) { if (value instanceof Date) { String str = new SimpleDateFormat(format).format((Date) value); return str; } return value == null ? null : value.toString(); } public String getFormat() { return format; } public void setFormat(String format) { this.format = format; } }
Json與javaBean之間的轉換工具類http://www.oschina.net/code/piece_full?code=17607
import java.lang.reflect.Field; import java.util.ArrayList; import java.util.HashMap; import java.util.Iterator; import java.util.List; import java.util.Map; import java.util.Set; import net.sf.json.JSONArray; import net.sf.json.JSONObject; import net.sf.json.JsonConfig; /** * Json與javaBean之間的轉換工具類 * * @author 晚風工作室 www.soservers.com * @version 20111221 * * {@code 現使用json-lib組件實現 * 需要 * json-lib-2.4-jdk15.jar * ezmorph-1.0.6.jar * commons-collections-3.1.jar * commons-lang-2.0.jar * 支持 * } */ public class JsonPluginsUtil { /** * 從一個JSON 對象字符格式中得到一個java對象 * * @param jsonString * @param beanCalss * @return */ @SuppressWarnings("unchecked") public static <T> T jsonToBean(String jsonString, Class<T> beanCalss) { JSONObject jsonObject = JSONObject.fromObject(jsonString); T bean = (T) JSONObject.toBean(jsonObject, beanCalss); return bean; } /** * 將java對象轉換成json字符串 * * @param bean * @return */ public static String beanToJson(Object bean) { JSONObject json = JSONObject.fromObject(bean); return json.toString(); } /** * 將java對象轉換成json字符串 * * @param bean * @return */ public static String beanToJson(Object bean, String[] _nory_changes, boolean nory) { JSONObject json = null; if(nory){//轉換_nory_changes里的屬性 Field[] fields = bean.getClass().getDeclaredFields(); String str = ""; for(Field field : fields){ // System.out.println(field.getName()); str+=(":"+field.getName()); } fields = bean.getClass().getSuperclass().getDeclaredFields(); for(Field field : fields){ // System.out.println(field.getName()); str+=(":"+field.getName()); } str+=":"; for(String s : _nory_changes){ str = str.replace(":"+s+":", ":"); } json = JSONObject.fromObject(bean,configJson(str.split(":"))); }else{//轉換除了_nory_changes里的屬性 json = JSONObject.fromObject(bean,configJson(_nory_changes)); } return json.toString(); } private static JsonConfig configJson(String[] excludes) { JsonConfig jsonConfig = new JsonConfig(); jsonConfig.setExcludes(excludes); // jsonConfig.setIgnoreDefaultExcludes(false); // // jsonConfig.setCycleDetectionStrategy(CycleDetectionStrategy.LENIENT); // jsonConfig.registerJsonValueProcessor(Date.class, // // new DateJsonValueProcessor(datePattern)); return jsonConfig; } /** * 將java對象List集合轉換成json字符串 * @param beans * @return */ @SuppressWarnings("unchecked") public static String beanListToJson(List beans) { StringBuffer rest = new StringBuffer(); rest.append("["); int size = beans.size(); for (int i = 0; i < size; i++) { rest.append(beanToJson(beans.get(i))+((i<size-1)?",":"")); } rest.append("]"); return rest.toString(); } /** * * @param beans * @param _no_changes * @return */ @SuppressWarnings("unchecked") public static String beanListToJson(List beans, String[] _nory_changes, boolean nory) { StringBuffer rest = new StringBuffer(); rest.append("["); int size = beans.size(); for (int i = 0; i < size; i++) { try{ rest.append(beanToJson(beans.get(i),_nory_changes,nory)); if(i<size-1){ rest.append(","); } }catch(Exception e){ e.printStackTrace(); } } rest.append("]"); return rest.toString(); } /** * 從json HASH表達式中獲取一個map,改map支持嵌套功能 * * @param jsonString * @return */ @SuppressWarnings({ "unchecked" }) public static Map jsonToMap(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).toString(); valueMap.put(key, value); } return valueMap; } /** * map集合轉換成json格式數據 * @param map * @return */ public static String mapToJson(Map<String, ?> map, String[] _nory_changes, boolean nory){ String s_json = "{"; Set<String> key = map.keySet(); for (Iterator<?> it = key.iterator(); it.hasNext();) { String s = (String) it.next(); if(map.get(s) == null){ }else if(map.get(s) instanceof List<?>){ s_json+=(s+":"+JsonPluginsUtil.beanListToJson((List<?>)map.get(s), _nory_changes, nory)); }else{ JSONObject json = JSONObject.fromObject(map); s_json += (s+":"+json.toString());; } if(it.hasNext()){ s_json+=","; } } s_json+="}"; return s_json; } /** * 從json數組中得到相應java數組 * * @param jsonString * @return */ public static Object[] jsonToObjectArray(String jsonString) { JSONArray jsonArray = JSONArray.fromObject(jsonString); return jsonArray.toArray(); } public static String listToJson(List<?> list) { JSONArray jsonArray = JSONArray.fromObject(list); return jsonArray.toString(); } /** * 從json對象集合表達式中得到一個java對象列表 * * @param jsonString * @param beanClass * @return */ @SuppressWarnings("unchecked") public static <T> List<T> jsonToBeanList(String jsonString, Class<T> beanClass) { JSONArray jsonArray = JSONArray.fromObject(jsonString); JSONObject jsonObject; T bean; int size = jsonArray.size(); List<T> list = new ArrayList<T>(size); for (int i = 0; i < size; i++) { jsonObject = jsonArray.getJSONObject(i); bean = (T) JSONObject.toBean(jsonObject, beanClass); list.add(bean); } return list; } /** * 從json數組中解析出java字符串數組 * * @param jsonString * @return */ public static String[] jsonToStringArray(String jsonString) { JSONArray jsonArray = JSONArray.fromObject(jsonString); String[] stringArray = new String[jsonArray.size()]; int size = jsonArray.size(); for (int i = 0; i < size; i++) { stringArray[i] = jsonArray.getString(i); } return stringArray; } /** * 從json數組中解析出javaLong型對象數組 * * @param jsonString * @return */ public static Long[] jsonToLongArray(String jsonString) { JSONArray jsonArray = JSONArray.fromObject(jsonString); int size = jsonArray.size(); Long[] longArray = new Long[size]; for (int i = 0; i < size; i++) { longArray[i] = jsonArray.getLong(i); } return longArray; } /** * 從json數組中解析出java Integer型對象數組 * * @param jsonString * @return */ public static Integer[] jsonToIntegerArray(String jsonString) { JSONArray jsonArray = JSONArray.fromObject(jsonString); int size = jsonArray.size(); Integer[] integerArray = new Integer[size]; for (int i = 0; i < size; i++) { integerArray[i] = jsonArray.getInt(i); } return integerArray; } /** * 從json數組中解析出java Double型對象數組 * * @param jsonString * @return */ public static Double[] jsonToDoubleArray(String jsonString) { JSONArray jsonArray = JSONArray.fromObject(jsonString); int size = jsonArray.size(); Double[] doubleArray = new Double[size]; for (int i = 0; i < size; i++) { doubleArray[i] = jsonArray.getDouble(i); } return doubleArray; } }
package com.mai.json; import static org.junit.Assert.assertEquals; 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.ezmorph.Morpher; import net.sf.ezmorph.MorpherRegistry; import net.sf.ezmorph.bean.BeanMorpher; import net.sf.json.JSONArray; import net.sf.json.JSONObject; import net.sf.json.util.JSONUtils; import org.apache.commons.beanutils.PropertyUtils; import org.junit.Test; public class JsonLibTest { /* * 普通類型、List、Collection等都是用JSONArray解析 * * Map、自定義類型是用JSONObject解析 * 可以將Map理解成一個對象,里面的key/value對可以理解成對象的屬性/屬性值 * 即{key1:value1,key2,value2......} * * 1.JSONObject是一個name:values集合,通過它的get(key)方法取得的是key后對應的value部分(字符串) * 通過它的getJSONObject(key)可以取到一個JSONObject,--> 轉換成map, * 通過它的getJSONArray(key) 可以取到一個JSONArray , * * */ //一般數組轉換成JSON @Test public void testArrayToJSON(){ boolean[] boolArray = new boolean[]{true,false,true}; JSONArray jsonArray = JSONArray.fromObject( boolArray ); System.out.println( jsonArray ); // prints [true,false,true] } //Collection對象轉換成JSON @Test public void testListToJSON(){ List list = new ArrayList(); list.add( "first" ); list.add( "second" ); JSONArray jsonArray = JSONArray.fromObject( list ); System.out.println( jsonArray ); // prints ["first","second"] } //字符串json轉換成json, 根據情況是用JSONArray或JSONObject @Test public void testJsonStrToJSON(){ JSONArray jsonArray = JSONArray.fromObject( "['json','is','easy']" ); System.out.println( jsonArray ); // prints ["json","is","easy"] } //Map轉換成json, 是用jsonObject @Test public void testMapToJSON(){ Map map = new HashMap(); map.put( "name", "json" ); map.put( "bool", Boolean.TRUE ); map.put( "int", new Integer(1) ); map.put( "arr", new String[]{"a","b"} ); map.put( "func", "function(i){ return this.arr[i]; }" ); JSONObject jsonObject = JSONObject.fromObject( map ); System.out.println( jsonObject ); } //復合類型bean轉成成json @Test public void testBeadToJSON(){ MyBean bean = new MyBean(); bean.setId("001"); bean.setName("銀行卡"); bean.setDate(new Date()); List cardNum = new ArrayList(); cardNum.add("農行"); cardNum.add("工行"); cardNum.add("建行"); cardNum.add(new Person("test")); bean.setCardNum(cardNum); JSONObject jsonObject = JSONObject.fromObject(bean); System.out.println(jsonObject); } //普通類型的json轉換成對象 @Test public void testJSONToObject() throws Exception{ String json = "{name=\"json\",bool:true,int:1,double:2.2,func:function(a){ return a; },array:[1,2]}"; JSONObject jsonObject = JSONObject.fromObject( json ); System.out.println(jsonObject); Object bean = JSONObject.toBean( jsonObject ); assertEquals( jsonObject.get( "name" ), PropertyUtils.getProperty( bean, "name" ) ); assertEquals( jsonObject.get( "bool" ), PropertyUtils.getProperty( bean, "bool" ) ); assertEquals( jsonObject.get( "int" ), PropertyUtils.getProperty( bean, "int" ) ); assertEquals( jsonObject.get( "double" ), PropertyUtils.getProperty( bean, "double" ) ); assertEquals( jsonObject.get( "func" ), PropertyUtils.getProperty( bean, "func" ) ); System.out.println(PropertyUtils.getProperty(bean, "name")); System.out.println(PropertyUtils.getProperty(bean, "bool")); System.out.println(PropertyUtils.getProperty(bean, "int")); System.out.println(PropertyUtils.getProperty(bean, "double")); System.out.println(PropertyUtils.getProperty(bean, "func")); System.out.println(PropertyUtils.getProperty(bean, "array")); List arrayList = (List)JSONArray.toCollection(jsonObject.getJSONArray("array")); for(Object object : arrayList){ System.out.println(object); } } //將json解析成復合類型對象, 包含List @Test public void testJSONToBeanHavaList(){ String json = "{list:[{name:'test1'},{name:'test2'}],map:{test1:{name:'test1'},test2:{name:'test2'}}}"; // String json = "{list:[{name:'test1'},{name:'test2'}]}"; Map classMap = new HashMap(); classMap.put("list", Person.class); MyBeanWithPerson diyBean = (MyBeanWithPerson)JSONObject.toBean(JSONObject.fromObject(json),MyBeanWithPerson.class , classMap); System.out.println(diyBean); List list = diyBean.getList(); for(Object o : list){ if(o instanceof Person){ Person p = (Person)o; System.out.println(p.getName()); } } } //將json解析成復合類型對象, 包含Map @Test public void testJSONToBeanHavaMap(){ //把Map看成一個對象 String json = "{list:[{name:'test1'},{name:'test2'}],map:{testOne:{name:'test1'},testTwo:{name:'test2'}}}"; Map classMap = new HashMap(); classMap.put("list", Person.class); classMap.put("map", Map.class); //使用暗示,直接將json解析為指定自定義對象,其中List完全解析,Map沒有完全解析 MyBeanWithPerson diyBean = (MyBeanWithPerson)JSONObject.toBean(JSONObject.fromObject(json),MyBeanWithPerson.class , classMap); System.out.println(diyBean); System.out.println("do the list release"); List<Person> list = diyBean.getList(); for(Person o : list){ Person p = (Person)o; System.out.println(p.getName()); } System.out.println("do the map release"); //先往注冊器中注冊變換器,需要用到ezmorph包中的類 MorpherRegistry morpherRegistry = JSONUtils.getMorpherRegistry(); Morpher dynaMorpher = new BeanMorpher( Person.class, morpherRegistry); morpherRegistry.registerMorpher( dynaMorpher ); Map map = diyBean.getMap(); /*這里的map沒進行類型暗示,故按默認的,里面存的為net.sf.ezmorph.bean.MorphDynaBean類型的對象*/ System.out.println(map); /*輸出: {testOne=net.sf.ezmorph.bean.MorphDynaBean@f73c1[ {name=test1} ], testTwo=net.sf.ezmorph.bean.MorphDynaBean@186c6b2[ {name=test2} ]} */ List<Person> output = new ArrayList(); for( Iterator i = map.values().iterator(); i.hasNext(); ){ //使用注冊器對指定DynaBean進行對象變換 output.add( (Person)morpherRegistry.morph( Person.class, i.next() ) ); } for(Person p : output){ System.out.println(p.getName()); /*輸出: test1 test2 */ } } } http://www.cnblogs.com/mailingfeng/archive/2012/01/18/2325707.html