Convert java Object to JSON string and EXCLUDE/IGNORE PROPERTIES using com.google.gson.Gson in java

Maven dependency -

<!-- https://mvnrepository.com/artifact/com.google.code.gson/gson -->
<dependency>
<groupId>com.google.code.gson</groupId>
<artifactId>gson</artifactId>
<version>2.8.5</version>
</dependency>


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Employee class

Include fields which contains @Expose
package com.ankit.json;

import java.util.Date;
import java.util.List;

import com.google.gson.annotations.Expose;

public class Employee {

    @Expose
    private int empId;
   
    @Expose
    private String name;

    private List<String> address;
   
    private Date birthDate;


    public Employee() {
          super();
    }
   
    public Employee(int empId, String name, List<String> address, Date birthDate) {
          super();
          this.empIdempId;
          this.namename;
          this.addressaddress;
          this.birthDate=birthDate;
    }
   
    @Override
    public String toString() {
          return "Employee [empId="empId", name="name", address="address", birthDate="birthDate"]";
    }
   

    //Setter and getters
    public int getEmpId() {
          return empId;
    }
    public void setEmpId(int empId) {
          this.empIdempId;
    }
    public String getName() {
          return name;
    }
    public void setName(String name) {
          this.namename;
    }
    public List<String> getAddress() {
          return address;
    }
    public void setAddress(List<String> address) {
          this.addressaddress;
    }
   
    public Date getBirthDate() {
          return birthDate;
    }

    public void setBirthDate(Date birthDate) {
          this.birthDatebirthDate;
    }

}


Convert java Object to JSON string and EXCLUDE/IGNORE PROPERTIES using com.google.gson.Gson in java

package com.ankit.json;

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

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;

public class CreateJsonUsingGoogleJson {
    public static void main(String[] args) {
          List<String> addesssnew ArrayList<>();
          addesss.add("Paris");
          addesss.add("London");

          Employee employeenew Employee(11, "ankit"addesssnew Date());

          Gson googleGsonnew GsonBuilder().setPrettyPrinting().excludeFieldsWithoutExposeAnnotation().create();
          String jsongoogleGson.toJson(employee); // Convert java object to JSON
                                                                         // string
          System.out.println("json = "+json); // Display
    }
}


//output
/*

json = {
"empId": 11,
"name": "ankit"
}

*/


Related links >

1. Jackson JSON -

We can use Jackson api for for processing JSON in java.

Jackson JSON examples


2. Java provides API (JSR 353) for Processing  JSON (JSR 353).
It provides -
  • Object Model API
  • Streaming API

Java API for JSON processing examples >



3. Simple  (simple.JSONObject)



4. Google Gson - processing java json


eEdit
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