基于json-lib.jar包Json范例程序(转)

基于json-lib.jar包Json实例程序 ? 创建JSONArray的常用四种方法 ? 1.从头或者从零开始，创建一个JSONArray(Creating a JSONArray from scratch) 实例1：? Java代码?? JSONArray?jsonArray?=?new?JSONArray().element("JSON").element("1").element("2.0").element("true");??? assertEquals("JSON",?jsonArray.getString(0));??? assertEquals(1,?jsonArray.getInt(1));??? assertEquals(2.0d,?jsonArray.getDouble(2),?0d);??? assertTrue(jsonArray.getBoolean(3));??? ??? 3.使用一个Collection来创建一个JSONArray(Creating a JSONArray from a Collection) 实例1： ?? Java代码?? List?list?=?new?ArrayList();?? ?list.add(?"JSON"?);??? list.add(?"1"?);??? list.add(?"2.0"?);??? list.add(?"true"?);??? JSONArray?jsonArray?=?(JSONArray)?JSONSerializer.toJSON(?list?);?assertEquals(?"JSON",?jsonArray.getString(0)?);??? assertEquals(?1,?jsonArray.getInt(1)?);??? assertEquals(?2.0d,?jsonArray.getDouble(2),?0d?);??? assertTrue(?jsonArray.getBoolean(3)?);??? ? ??? 4.使用一个Array来创建一个JSONArray(Creating a JSONArray from an array) 实例1： Java代码?? Object[]?array?=?new?Object[]?{?"JSON",?1,?2.0,?true?};??? JSONArray?jsonArray?=?(JSONArray)?JSONSerializer.toJSON(array);?assertEquals("JSON",?jsonArray.getString(0));?? assertEquals(1,?jsonArray.getInt(1));??? assertEquals(2.0d,?jsonArray.getDouble(2),?0d);??? assertTrue(jsonArray.getBoolean(3));??? ?? //实例2：??? Object[]?array?=?new?Object[]?{?"JSON",?1,?2.0,?true?};??? JSONArray?jsonArray?=?JSONArray.fromObject(array);??? assertEquals("JSON",?jsonArray.getString(0));??? assertEquals(1,?jsonArray.getInt(1));??? assertEquals(2.0d,?jsonArray.getDouble(2),?0d);??? assertTrue(jsonArray.getBoolean(3));??? ???? 由此可见，无论要转换的源是哪种类型，都可以使用(JSONArray) JSONSerializer.toJSON()或JSONArray.fromObject()来转换; ? ?? 常用的三种扩展功能? ? 1.使用一个JSON格式化字符串来创建一个JSONFunction(JavaScript functions)?? 实例： Java代码?? String?str?=?"{func:?function(?param?){?doSomethingWithParam(param);?}}";??? JSONObject?jsonObject?=?(JSONObject)?JSONSerializer.toJSON(str);?JSONFunction?func?=?(JSONFunction)?jsonObject.get("func");?ArrayAssertions.assertEquals(new?String[]?{?"param"?},?func.getParams());??? assertEquals("doSomethingWithParam(param);",?func.getText());??? ???? ? 注：函数的写法要注意function(){},参数param是可选的！ 2.排除一个JSON格式化字符串的某些属性(Exclude properties) 实例： ??? Java代码?? String?str?=?"{'string':'JSON',?'integer':?1,?'double':?2.0,?'boolean':?true}";??? JsonConfig?jsonConfig?=?new?JsonConfig();??? jsonConfig.setExcludes(new?String[]?{?"double",?"boolean"?});?JSONObject?jsonObject?=?(JSONObject)?JSONSerializer.toJSON(str,?jsonConfig);??? assertEquals("JSON",?jsonObject.getString("string"));??? assertEquals(1,?jsonObject.getInt("integer"));?? assertFalse(jsonObject.has("double"));??? assertFalse(jsonObject.has("boolean"));??? ???? 3.排除一个JSON格式化字符串的某些属性,使用过滤器(Exclude properties (with filters) 实例： ?? Java代码?? String?str?=?"{'string':'JSON',?'integer':?1,?'double':?2.0,?'boolean':?true}";?? ?JsonConfig?jsonConfig?=?new?JsonConfig();?jsonConfig.setJsonPropertyFilter(new?PropertyFilter()?{??? ???public?boolean?apply(Object?source,?String?name,?Object?value)?{?? ?????????if?("double".equals(name)?||?"boolean".equals(name))??? ??????????{?return?true;?}?? ??????????????return?false;?}?});??? JSONObject?jsonObject?=?(JSONObject)?JSONSerializer.toJSON(str,?jsonConfig);??? assertEquals("JSON",?jsonObject.getString("string"));??? assertEquals(1,?jsonObject.getInt("integer"));??? assertFalse(jsonObject.has("double"));??? assertFalse(jsonObject.has("boolean"));??? ? ? JSONObject-Java常用的四种用法 1.JSONObject to DynaBean Java代码?? String?json?=?"{name=\"json\",bool:true,int:1,double:2.2}";?JSONObject?jsonObject?=?JSONObject.fromObject(json);?//抽象的写法：DynaBean?bean?=?(DynaBean)?JSONSerializer.toJava(?jsonObject?);?Object?bean?=?JSONObject.toBean(jsonObject);??? //Object?bean1?=?JSONSerializer.toJava(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"));??? ?? ??? ? ?2.JSONObject to JavaBean Java代码?? String?json?=?"{name:\"zhangsan\",age:25,hight:1.72,sex:true}";?JSONObject?jsonObject?=?JSONObject.fromObject(json);??? UserBean?bean?=?(UserBean)?JSONObject.toBean(jsonObject,?UserBean.class);??? System.out.println(jsonObject);??? ? ? 3.JSONArray to List Java代码?? String?json?=?"[\"first\",\"second\"]";??? JSONArray?jsonArray?=?(JSONArray)?JSONSerializer.toJSON(json);?? ?List?output?=?(List)?JSONSerializer.toJava(jsonArray);??? ???? 4.JSONArray to array ? ? Java代码?? String?json?=?"[\"first\",\"second\"]";?? ?JSONArray?jsonArray?=?(JSONArray)?JSONSerializer.toJSON(json);?JsonConfig?jsonConfig?=?new?JsonConfig();??? jsonConfig.setArrayMode(JsonConfig.MODE_OBJECT_ARRAY);??? Object[]?output?=?(Object[])?JSONSerializer.toJava(jsonArray,?jsonConfig);??? Object[]?expected?=?new?Object[]?{?"first",?"second"?};?ArrayAssertions.assertEquals(expected,?output);???? ??? ? 理论上，这样就可以了，但时，有异常Caused by: java.lang.NoSuchMethodException: com.json.Json$UserBean.<init>() ??? 2.使用一个JSON格式化字符串来创建一个JSONArray(Creating a JSONArray from a JSON formatted string)?? 实例1： ?? Java代码?? String?str?=?"['JSON',?1,?2.0,?true]";?//注意该字符串的格式"[?,?]"?JSONArray?jsonArray?=?(JSONArray)?JSONSerializer.toJSON(?str?);?assertEquals(?"JSON",?jsonArray.getString(0)?);??? assertEquals(?1,?jsonArray.getInt(1)?);??? assertEquals(?2.0d,?jsonArray.getDouble(2),?0d?);??? assertTrue(?jsonArray.getBoolean(3)?);??? ????

?List<String> list = new ArryList<String>(); list.add("a"); list.add("b"); Map<String,List<String>> map = new HashMap<String,List<String>>(); map.put("list",list); MessageUtils.outputJSONResult(JSONObject.fromObject(map).toString(), response); public class MessageUtils { public static void outputJSONResult(String result, HttpServletResponse response) { try { response.setHeader("ContentType", "text/json"); response.setCharacterEncoding("utf-8"); PrintWriter pw = response.getWriter(); pw.write(result); pw.flush(); pw.close(); } catch (IOException e) { e.printStackTrace(); } }