基于java反射机制实现javabean转json字符串
package com.ObjectToJson;

import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Iterator;

public class ObjectToJson {


public  static String ObjListToJson(ArrayList<?> list){
StringBuilder build=new StringBuilder();
//迭代器
Iterator<?> iterator=list.iterator();
build.append("[");
String separate="";
while(iterator.hasNext()){
build.append(separate);
//object转json字符串
String str=ObjToJson(iterator.next());
build.append(str);
separate=",";
}
build.append("]");
return build.toString();
}

@SuppressWarnings("unchecked")
public  static String ObjToJson(Object obj){
StringBuilder build=new StringBuilder();
build.append("{");
@SuppressWarnings("rawtypes")
Class cla=null;
try {
//反射加载类
cla=Class.forName(obj.getClass().getName());
} catch (ClassNotFoundException e) {
System.out.println(obj.getClass().toString().concat(" 未找到这个类"));
e.printStackTrace();
return null;
}

StringBuffer methodname=new StringBuffer();
//获取java类的变量
Field[] fields=cla.getDeclaredFields();
String separate="";
for(Field temp:fields){
build.append(separate);
build.append("\"");
build.append(temp.getName());
build.append("\":");

methodname.append("get");
methodname.append(temp.getName().substring(0,1).toUpperCase());
methodname.append(temp.getName().substring(1));

build.append("\"");
Method method=null;
try {
//获取java的get方法
method=cla.getMethod(methodname.toString());
} catch (NoSuchMethodException | SecurityException e) {
methodname.setLength(0);
e.printStackTrace();
}

try {
//执行get方法，获取变量参数的直。
build.append(method.invoke(obj));
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (IllegalArgumentException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}

build.append("\"");
methodname.setLength(0);
separate=",";
}

build.append("}");
return build.toString();
}
}