任意物件轉換成JSON

只支援字元和基本型別

程式碼

package ztf.question3;

public class Address {
    private String province;
    private String street;
    public Address() {

    }
    public Address(String pro,String street){
        this.province=pro;
        this.street=street;
    }
    public String getProvince
 
(){
        return this.province;
    }
    public void setProvince(String province){
        this.province=province;
    }
    public String getStreet(){
        return this.street;
    }
    public void setStreet(String street){
        this.street=street;
    }
    @Override
    public String toString
 
() {
        return "Address [province=" + province + ", street=" + street + "]";
    }

}

package ztf.question3;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileWriter;

import net.sf.json.JSON;
import net.sf.json.JSONSerializer;


public class Application {

    public static void main(String[] args){
        Person person=new Person();
 

        person.setName("ddd");
        person.setAge(23);
        Address address=new Address("chonqqing","Hong Guang Street");
        person.setAddress(address);

        System.out.println(ObjectToJson.writeJson(person.getClass(), person));
    }

}

package ztf.question3;

import java.lang.reflect.Field;
import java.lang.reflect.Method;

public class ObjectToJson {
    public static String writeJson(Class clazz,Object obj){
        StringBuilder stringBuilder=new StringBuilder();
        try{
            stringBuilder.append("{");
            Field[] declaredFields = clazz.getDeclaredFields();
            for(Field field:declaredFields) {
                field.setAccessible(true);
                stringBuilder.append("\""+field.getName()+"\":");
                Class<?> type = field.getType();
                if(type.isPrimitive()||type==String.class) {
                     Method m = (Method) clazz.getMethod(  
                                "get" + getMethodName(field.getName())); 
                    stringBuilder.append("\""+m.invoke(obj)+"\"");
                }else {
                     Method m = (Method) clazz.getMethod(  
                                "get" + type.getSimpleName());  
                     stringBuilder.append(writeJson(field.getType(),m.invoke(obj)));
                }
                stringBuilder.append(",");
            }
            return reChange(stringBuilder.toString());
        }catch(Exception e){
            e.printStackTrace();
        }
        return null;
    }

    private static String reChange(String string) {
        // TODO Auto-generated method stub
        return string.substring(0,string.length()-1)+"}";
    }

    private static String getMethodName(String name) {
        // TODO Auto-generated method stub
        return  name.substring(0, 1).toUpperCase() + name.substring(1);
    }
}

package ztf.question3;

public class Person {
    private String name;
    private int age;
    private Address address;
    public Person(){
        this.name="";
    }
    public String getName(){
        return this.name;
    }
    public void setName(String name){
        this.name=name;
    }
    public int getAge(){
        return this.age;
    }
    public void setAge(int age){
        this.age=age;
    }
    public Address getAddress(){
        return this.address;
    }
    public void setAddress(Address address){
        this.address=address;
    }
    @Override
    public String toString() {
        return "Person [name=" + name + ", age=" + age + ", address=" + address + "]";
    }

}

json轉換成指定物件

需要修改程式碼才能支援其他型別

程式碼

package ztf.question4;


import ztf.question3.Person;

public class Application {

    public static void main(String[] args){
        String json=new String("{\"name\":\"ddd\",\"age\":\"23\",\"address\":{\"province\":\"chonqqing\",\"street\":\"Hong Guang Street\"}}\r\n" + 
                "");
        System.out.println((Person)JsonToPerson.readJson(json,Person.class));
    }

}

package ztf.question4;


import java.lang.reflect.Field;
import java.lang.reflect.Method;


import net.sf.json.JSONObject;
import ztf.question3.Address;

public class JsonToPerson {
    public static Object readJson(String json,Class class1) {
         JSONObject jsoj = JSONObject.fromObject(json);
        try {

            Object obj=class1.newInstance();
            Field[] fields = class1.getDeclaredFields();
            for(Field field:fields) {
                Class<?> type = field.getType();
                Method method = class1.getMethod("set"+getMethodName(field.getName()),type);
                if(type.isPrimitive()||"java.lang.String".equals(type.getName())) {
                    //這裡應該有更好的解決方法，需要檢視其他框架的原始碼
                    if("java.lang.String".equals(type.getName())) {
                        method.invoke(obj, jsoj.get(field.getName()));
                    }else if("int".equals(type.getName())){
                        method.invoke(obj, Integer.valueOf(jsoj.get(field.getName()).toString()));
                    }

                }else {
                    method.invoke(obj, (Address)readJson(jsoj.get(field.getName()).toString(),type));

                }
            }
            return obj;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }



    private static String fixEleName(String name) {
        int lastIndexOf = name.lastIndexOf('.');
        if(lastIndexOf<=-1)
            return name;
        return name.substring(lastIndexOf+1, lastIndexOf+2).toLowerCase()+name.substring(lastIndexOf+2);
    }


    private static String getMethodName(String name) {
        // TODO Auto-generated method stub
        return  name.substring(0, 1).toUpperCase() + name.substring(1);
    }
}