提取对象属性值转换为json格式的数据

import java.lang.reflect.Field;import java.util.Collection;import java.util.Iterator;/** 将pojo对象的属性值提取出来，组成json格式的数据* 当前版本只能对最基本的pojo对象进行转化，类似于下面的格式：  public class Pojo {private String name;private int age;    public int getAge() {    return age;    }       public String getName() {    return name;    }       public void setAge(int age) {    this.age = age;    }       public void setName(String name) {    this.name = name;    }  }* 单个对象返回{'name':age}格式；集合对象返回{'name':age},{'name':age}...* * author：scriptguy* date：  2010/04/06*/public class JsonUtil {/*** 暴露出来的方法，传入需要将属性值转换为json数据格式的pojo** 会抛出IllegalAccessException异常，需要捕捉*/public static String toJson(Object obj) throws IllegalAccessException{Class cla = obj.getClass();Field[] fields = cla.getDeclaredFields();String[] names = fieldToNames(fields);Object[] values = fieldToValues(fields,obj);String json = produceToJson(names,values);return json;}private static String[] fieldToNames(Field[] fields) {String[] names = new String[fields.length];for(int i = 0;i < fields.length;i++) {fields[i].setAccessible(true);//将此对象的 accessible 标志设置为可以读取names[i] = fields[i].getName();}return names;}private static Object[] fieldToValues(Field[] fields,Object obj) throws IllegalAccessException{Object[] values = new Object[fields.length];for(int i = 0;i < fields.length;i++) {values[i] = fields[i].get(obj);}return values;}private static String produceToJson(String[] names,Object[] values) {if(names.length != values.length) {new RuntimeException("转化json数据出错！！！");}StringBuilder json = new StringBuilder();json.append("{");for(int i = 0;i < names.length;i++) {json.append("'");json.append(names[i]);json.append("':");processFieldValue(values[i],json);if(i < names.length - 1) {json.append(",");}}json.append("}");return json.toString();}private static void processFieldValue(Object obj,StringBuilder json) {if(obj instanceof Number) {json.append(obj);} else {json.append("'");json.append(obj);json.append("'");}}public static String allToJson(Collection coll) throws IllegalAccessException{Iterator iterator = coll.iterator();StringBuilder json = new StringBuilder();Object obj;while(iterator.hasNext()) {obj = iterator.next();json.append(toJson(obj));json.append(",");}int delete = json.lastIndexOf(",");json = json.deleteCharAt(delete);return json.toString();}/****/}

?测试代码

import java.util.Collection;import java.util.*;public class TestJsonUtil {public static void main(String[] args) throws Exception{Pojo pojo1 = new Pojo("list",23);Pojo pojo = new Pojo("scriptguy",22);List<Object> lista = new ArrayList<Object>();lista.add(pojo1);lista.add(pojo);System.out.println(JsonUtil.allToJson(lista));}}

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结果：
????? {'name':'list','age':23},{'name':'scriptguy','age':22}