Fastjson--json/JSONObject/Bean常用转换

╰半夏微凉° 2022-01-26 12:59 434阅读 0赞

## 首先贴上fastjson的guthub地址：[https://github.com/alibaba/fastjson][https_github.com_alibaba_fastjson] ##

# #

## 本文先创建几个实体类和几个json字符串，然后做转换示例 ##

##    1.创建实体类Teacher.java ##

package com.imooc.sell.json;
     
    import java.util.List;
     
    public class Teacher {
        private String teacherName;
        private Integer teacherAge;
        private Course course;
        private List<Student> students;
     
        public String getTeacherName() {
            return teacherName;
        }
     
        public void setTeacherName(String teacherName) {
            this.teacherName = teacherName;
        }
     
        public Integer getTeacherAge() {
            return teacherAge;
        }
     
        public void setTeacherAge(Integer teacherAge) {
            this.teacherAge = teacherAge;
        }
     
        public Course getCourse() {
            return course;
        }
     
        public void setCourse(Course course) {
            this.course = course;
        }
     
        public List<Student> getStudents() {
            return students;
        }
     
        public void setStudents(List<Student> students) {
            this.students = students;
        }
     
        public Teacher(String teacherName, Integer teacherAge, Course course, List<Student> students) {
            this.teacherName = teacherName;
            this.teacherAge = teacherAge;
            this.course = course;
            this.students = students;
        }
     
        public Teacher() {
        }
     
        @Override
        public String toString() {
            return "Teacher{" +
                    "teacherName='" + teacherName + '\'' +
                    ", teacherAge=" + teacherAge +
                    ", course=" + course +
                    ", students=" + students +
                    '}';
        }
    }

##    2.创建实体类Course.java ##

package com.imooc.sell.json;
     
    public class Course {
     
        private String courseName;
        private Integer code;
     
        public String getCourseName() {
            return courseName;
        }
     
        public void setCourseName(String courseName) {
            this.courseName = courseName;
        }
     
        public Integer getCode() {
            return code;
        }
     
        public void setCode(Integer code) {
            this.code = code;
        }
     
        public Course() {
        }
     
        public Course(String courseName, Integer code) {
            this.courseName = courseName;
            this.code = code;
        }
     
        @Override
        public String toString() {
            return "Course{" +
                    "courseName='" + courseName + '\'' +
                    ", code=" + code +
                    '}';
        }
    }

##    3.创建实体类Student.java ##

package com.imooc.sell.json;
     
    public class Student {
     
        private String studentName;
        private Integer studentAge;
     
        public Student() {
        }
     
        public String getStudentName() {
     
            return studentName;
        }
     
        public void setStudentName(String studentName) {
            this.studentName = studentName;
        }
     
        public Integer getStudentAge() {
            return studentAge;
        }
     
        public void setStudentAge(Integer studentAge) {
            this.studentAge = studentAge;
        }
     
        public Student(String studentName, Integer studentAge) {
            this.studentName = studentName;
            this.studentAge = studentAge;
        }
     
        @Override
        public String toString() {
            return "Student{" +
                    "studentName='" + studentName + '\'' +
                    ", studentAge=" + studentAge +
                    '}';
        }
    }

##    4.创建测试代码   package com.imooc.sell.json; ##

/*
    *
    * 学习fastjson
    * Date:2018-08-01
    * */
     
    import com.alibaba.fastjson.JSONArray;
    import com.alibaba.fastjson.JSONObject;
    import org.junit.Test;
    import org.junit.runner.RunWith;
    import org.springframework.boot.test.context.SpringBootTest;
    import org.springframework.test.context.junit4.SpringRunner;
     
    @RunWith(SpringRunner.class)
    @SpringBootTest
    public class FastJsonTest {
     
        //json字符串-简单对象型
        private static final String  JSON_OBJ_STR = "{\"studentName\":\"lily\",\"studentAge\":12}";
     
        //json字符串-数组类型
        private static final String  JSON_ARRAY_STR = "[{\"studentName\":\"lily\",\"studentAge\":12},{\"studentName\":\"lucy\",\"studentAge\":15}]";
     
        //复杂格式json字符串
        private static final String  COMPLEX_JSON_STR = "{\"teacherName\":\"crystall\",\"teacherAge\":27,\"course\":{\"courseName\":\"english\",\"code\":1270},\"students\":[{\"studentName\":\"lily\",\"studentAge\":12},{\"studentName\":\"lucy\",\"studentAge\":15}]}";
     
     
    /*
    * 1.JSON格式字符串与JSON对象之间的转换
    */
     
        @Test
        public void testComplexJSONStrToJSONObject(){
     
            /*
            * 复杂json格式字符串与JSONObject之间的转换
            * */
            JSONObject jsonObject = JSONObject.parseObject(COMPLEX_JSON_STR);
            //获取单值
            System.out.println(jsonObject.get("teacherName"));
            //获取json对象
            JSONObject course = jsonObject.getJSONObject("course");
            System.out.println(course.get("courseName"));
            //获取数组
            JSONArray students = jsonObject.getJSONArray("students");
            System.out.println(students.getJSONObject(1).get("studentName"));
     
        }
     
        /**
         * 复杂JSONObject到json格式字符串的转换
         */
        @Test
        public void testJSONObjectToComplexJSONStr() {
            //复杂JSONObject,目标要转换为json字符串
            JSONObject jsonObject = JSONObject.parseObject(COMPLEX_JSON_STR);
     
            String string = jsonObject.toString();
            System.out.println(string);
     
        }
     
        /*
        *
        *2.JSON格式字符串与javaBean之间的转换
        *
        */
        @Test
        public void testComplexJSONStrToJavaBean(){
            /**
             * 复杂json格式字符串到JavaBean_obj的转换
             */
            //使用Gson思想
            Teacher teacher = JSONObject.parseObject(COMPLEX_JSON_STR,Teacher.class);
     
            System.out.println(teacher.getTeacherName());
            System.out.println(teacher.getCourse().getCourseName());
            System.out.println(teacher.getStudents().get(1).getStudentName());
     
        }
     
        /**
         * 复杂JavaBean_obj到json格式字符串的转换
         */
     
        @Test
        public void testJavaBeanToComplexJSONStr(){
            //先转成Bean
            Teacher teacher = JSONObject.parseObject(COMPLEX_JSON_STR,Teacher.class);
     
            //转成json字符串
            String jsonString = JSONObject.toJSONString(teacher);
            System.out.println(jsonString);
        }
     
        /*
        *
        * 3.javaBean与json对象间的之间的转换
        *
        * */
     
        /**
         * 复杂JavaBean_obj到json对象的转换
         */
        @Test
        public void testComplexJavaBeanToJSONObject(){
            //先转成Bean
            Teacher teacher = JSONObject.parseObject(COMPLEX_JSON_STR,Teacher.class);
     
            //转成json对象
            JSONObject jsonObject = (JSONObject) JSONObject.toJSON(teacher);
            System.out.println(jsonObject.getJSONObject("course").get("courseName"));
        }
     
     
        /**
         * 复杂json对象到JavaBean_obj的转换
         */
        @Test
        public void testComplexJSONObjectToJavaBean(){
     
            //先转成Bean
            Teacher teacher = JSONObject.parseObject(COMPLEX_JSON_STR,Teacher.class);
     
            //转成json对象
            JSONObject jsonObject = (JSONObject) JSONObject.toJSON(teacher);
     
            //转成Bean
            Teacher teacher1 = JSONObject.parseObject(JSONObject.toJSONString(jsonObject), Teacher.class);
     
            System.out.println(teacher1.getTeacherName());
            System.out.println(teacher1.getCourse().getCourseName());
            System.out.println(teacher1.getStudents().get(1).getStudentName());
     
     
        }
     
    }

原文：https://blog.csdn.net/a1032818891/article/details/81334874

[https_github.com_alibaba_fastjson]: https://github.com/alibaba/fastjson