Java中JSONlib包使用总结 - 易学教程，面试笔记经验！

Java Json常用方法

JSON-lib包是一个beans,collections,maps,java arrays,XML和JSON互相转换的包，可以将Java对象转成json格式的字符串，也可以将Java对象转换成xml格式的文档，同样可以将json字符串转换成Java对象或是将xml字符串转换成Java对象。

JSON-lib下载

JSON-lib包下载地址：https://repo1.maven.org/maven2/net/sf/json-lib/json-lib/2.4/json-lib-2.4-jdk15.jar
JSON-lib 依赖的包，且不得低于以下版本：
jakarta commons-lang 2.5
jakarta commons-beanutils 1.8.0
jakarta commons-collections 3.2.1
jakarta commons-logging 1.1.1
ezmorph 1.0.6
打包下载：json-lib-all.zip

JSON-lib安装

1. Idea 中导入json包的方法。

ctrl+alt+shift+S 打开项目结构，依次点击Libraries->+加号。

Java中JSON-lib包

将刚才下载的jar文件导入我们的项目

2.maven 安装

<dependency>
    <groupId>net.sf.json-lib</groupId>
    <artifactId>json-lib</artifactId>
    <version>2.4</version>
</dependency>

因为JSON-lib包依赖的包过多，建议使用maven安装的方法安装JSON-lib包

JSON-lib中Json字符串转对象

将Json字符串转成Java对象

 import net.sf.json.JSONObject;

/**
 *6. 将json字符串转成Java对象
 */
public class readJSON2Bean {
    public static void main(String args[]) {
        String json = "{\"address\":\"wuhan\",\"birthday\":\"2010-11-22\"," +
                "\"email\":\"email@123.com\",\"id\":22,\"name\":\"yxjc123\"}";
        JSONObject jsonObject = JSONObject.fromObject(json);
        Student stu = (Student) JSONObject.toBean(jsonObject, Student.class);
        System.out.println(stu.toString());
    }

    //这里方便设置为静态内部类
    public static class Student{
		
		@Override
		public String toString() {
			return "Student{" +
					"address='" + address + '\'' +
					", name='" + name + '\'' +
					", email='" + email + '\'' +
					", birthday='" + birthday + '\'' +
					", id=" + id +
					'}';
		}
		
        private String address;
        private String name;
        private String email;
        private String birthday;
        private Integer id;

        public String getAddress() {
            return address;
        }

        public void setAddress(String address) {
            this.address = address;
        }

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public String getEmail() {
            return email;
        }

        public void setEmail(String email) {
            this.email = email;
        }

        public String getBirthday() {
            return birthday;
        }

        public void setBirthday(String birthday) {
            this.birthday = birthday;
        }

        public Integer getId() {
            return id;
        }

        public void setId(Integer id) {
            this.id = id;
        }
    }


}

测试一下

输出

Student{address='wuhan', name='yxjc123', email='email@123.com', birthday='2010-11-22', id=22}

将Json字符串转成Java的List集合

import net.sf.json.JSONArray;
import java.util.List;

/**
 *JSON字符串转成Java的List集合
 */
public class readJSON2List {
    public static void main(String args[]) {
        try {
            String json = "{\"address\":\"wuhan\",\"birthday\":\"2010-11-22\"," +
                    "\"email\":\"email@123.com\",\"id\":22,\"name\":\"yxjc123\"}";
            json = "[" + json + "]";
            JSONArray jsonArray = JSONArray.fromObject(json);
            List< Student > list = JSONArray.toList(jsonArray, Student.class);
            System.out.println(list.size());
            System.out.println(list.get(0));
            list = JSONArray.toList(jsonArray);
            System.out.println(list.size());
            System.out.println(list.get(0)); 
        } catch(Exception e) {
            e.printStackTrace();
        }
    }

    //这里方便设置为静态内部类
    public static class Student{
        private String address;
        private String name;
        private String email;
        private String birthday;
        private Integer id;

        public String getAddress() {
            return address;
        }

        public void setAddress(String address) {
            this.address = address;
        }

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public String getEmail() {
            return email;
        }

        public void setEmail(String email) {
            this.email = email;
        }

        public String getBirthday() {
            return birthday;
        }

        public void setBirthday(String birthday) {
            this.birthday = birthday;
        }

        public Integer getId() {
            return id;
        }

        public void setId(Integer id) {
            this.id = id;
        }
    }


}

测试一下

输出：

1
readJSON2List$Student@4926097b
1
net.sf.ezmorph.bean.MorphDynaBean@59f95c5d[
{birthday=2010-11-22, address=wuhan, name=yxjc123, id=22, email=email@123.com}
]

将Json字符串转换成动态Java对象

 import net.sf.json.JSON;
import net.sf.json.JSONObject;
import net.sf.json.JSONSerializer;
import org.apache.commons.beanutils.PropertyUtils;

import java.lang.reflect.InvocationTargetException;

/**
 *将json字符串转换成动态Java对象
 */
public class readJSON2DynaBean {
    public static void main(String args[]) {
        try {
            String json = "{\"address\":\"wuhan\",\"birthday\":\"2010-11-22\"," +
                    "\"email\":\"email@123.com\",\"id\":22,\"name\":\"yxjc123\"}";
            JSON jo = JSONSerializer.toJSON(json);
            Object o = JSONSerializer.toJava(jo);
            System.out.println(PropertyUtils.getProperty(o, "address").toString());
            JSONObject jsonObject = JSONObject.fromObject(json);
            System.out.println((jsonObject.getString("email")));
            o = JSONSerializer.toJava(jsonObject);
            System.out.println((PropertyUtils.getProperty(o, "name").toString()));
        } catch(IllegalAccessException e) {
            e.printStackTrace();
        } catch(InvocationTargetException e) {
            e.printStackTrace();
        } catch(NoSuchMethodException e) {
            e.printStackTrace();
        }
    }

    //这里方便设置为静态内部类
    public static class Student{
        private String address;
        private String name;
        private String email;
        private String birthday;
        private Integer id;

        public String getAddress() {
            return address;
        }

        public void setAddress(String address) {
            this.address = address;
        }

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public String getEmail() {
            return email;
        }

        public void setEmail(String email) {
            this.email = email;
        }

        public String getBirthday() {
            return birthday;
        }

        public void setBirthday(String birthday) {
            this.birthday = birthday;
        }

        public Integer getId() {
            return id;
        }

        public void setId(Integer id) {
            this.id = id;
        }
    }


}

测试一下

输出

wuhan
email@123.com
yxjc123

将Json字符串转成xml对象

import net.sf.json.JSONObject;
import net.sf.json.xml.XMLSerializer;

/**
 * Json转换Xml对象
 */
public class json2xml {
    public static void main(String args[]) {
        String json1 = "{'age':22,'sex':'男','userName':'yxjc123'}";
        JSONObject jsonObj = JSONObject.fromObject(json1);
        XMLSerializer x = new XMLSerializer();
        String xml = x.write(jsonObj);
        System.out.println("XML");
        System.out.println(xml);
    }

}

测试一下

输出

XML

22男yxjc123

JSON-lib中对象转Json字符串

Map集合转换成json字符串方法

import net.sf.json.JSONObject;
import java.util.HashMap;
import java.util.Map;

public class MapToJSON {
    public static void main(String[] args) {
        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 json = JSONObject.fromObject(map);
        System.out.println(json);
    }

}

测试一下

数组转换成json字符串方法

import net.sf.json.JSONArray;

public class BeanToJSON {
    public static void main(String[] args) {
        boolean[] boolArray = new boolean[] { true, false, true };
        JSONArray jsonArray1 = JSONArray.fromObject(boolArray);
        System.out.println(jsonArray1);
    }
}

测试一下

Java对象转换成json字符串方法

 import net.sf.json.JSONArray;

import java.util.ArrayList;
import java.util.List;

/**
 * 使用json-lib javabean转json
 */
public class BeanToJSON {

    /**
     * @param args
     */
    public static void main(String[] args) {
        List list = new ArrayList();
        JsonBean2 jb1 = new JsonBean2();
        jb1.setCol(1);
        jb1.setRow(1);
        jb1.setValue("xx");

        JsonBean2 jb2 = new JsonBean2();
        jb2.setCol(2);
        jb2.setRow(2);
        jb2.setValue("");

        list.add(jb1);
        list.add(jb2);
        JSONArray ja = JSONArray.fromObject(list);
        System.out.println(ja);
    }

    public static  class JsonBean2{
        private String value;
        private Integer col;
        private Integer row;

        public String getValue() {
            return value;
        }

        public void setValue(String value) {
            this.value = value;
        }

        public Integer getCol() {
            return col;
        }

        public void setCol(Integer col) {
            this.col = col;
        }

        public Integer getRow() {
            return row;
        }

        public void setRow(Integer row) {
            this.row = row;
        }
    }
}

测试一下

Collections转换Json字符串方法

 import net.sf.json.JSONArray;

import java.util.ArrayList;
import java.util.List;

/**
 * 集合转json
 */
public class CollectionToJSON {

    /**
     * main
     */
    public static void main(String[] args) {
        List list1 = new ArrayList();
        list1.add("first");
        list1.add("second");
        JSONArray jsonArray1 = JSONArray.fromObject(list1);
        System.out.println("List list1");
        System.out.println(jsonArray1);
        List < Student > list2 = new ArrayList < Student > ();
        list2.add(new Student("stu1", "男", 10));
        list2.add(new Student("stu2", "女", 11));
        list2.add(new Student("stu3", "男", 12));
        JSONArray jsonArray2 = JSONArray.fromObject(list2);
        System.out.println("List<Student> list2");
        System.out.println(jsonArray2);
    }

    public static class Student{
        private String name;
        private String sex;
        private Integer age;

        public Student(String name, String sex, int age) {
            this.name = name;
            this.age = age;
            this.sex = sex;
        }

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public String getSex() {
            return sex;
        }

        public void setSex(String sex) {
            this.sex = sex;
        }

        public Integer getAge() {
            return age;
        }

        public void setAge(Integer age) {
            this.age = age;
        }
    }

}

测试一下

Xml转换Json字符串方法

 import net.sf.json.JSON;
import net.sf.json.xml.XMLSerializer;

public class XmlToJSON {
    public static void main(String[] args) {
        String s = "\n" +
    "                        zs\n" +
    "                        男\n" +
    "                        20\n" +
    "               ";
        XMLSerializer x = new XMLSerializer();
        JSON json = x.read(s);
        System.out.println("XmlToJson");
        System.out.println(json.toString());

    }

}

测试一下

输出

XmlToJson
{"name":{"@id":"n1","#text":"zs"},"sex":"男","age":"20"}