Convert Java Object to Json using GSON

JSON stands for JavaScript object notation, is a lightweight format for storing and transporting the data. It stores the data as the key-value pair. Most of the applications use this format for transmitting the data from the server to the web page, or vice-versa. However, we must convert the java object to JSON string to transmit it over the network. In Java, we can use the following methods to convert a Java object to Json.

GSON: It is a java library that contains methods to serialize and deserialize Java objects to JSON. It is open-source.
Jackson API

In this tutorial, we will convert the Java object to JSON using the GSON library. Consider the following steps to convert the Java object to JSON.

1. Create a maven project in eclipse and use pom.xml to add GSON dependencies.

<dependency> 
<groupId>com.google.code.gson</groupId> 
<artifactId>gson</artifactId> 
<version>2.6.2</version> 
</dependency>

2. Create a Plain Old Java Object (POJO) that is to be converted into Json. Consider the following java code to create the java object.

package com.convertJSON;


public class Company {
private String companyName;
private String companyTagline;
private int employees;

public String getCompanyName() {
return companyName;
}

public void setCompanyName(String companyName) {
this.companyName = companyName;
}

public String getCompanyTagline() {
return companyTagline;
}

public void setCompanyTagline(String companyTagline) {
this.companyTagline = companyTagline;
}

public int getEmployees() {
return employees;
}

public void setEmployees(int employees) {
this.employees = employees;
}

@Override
public String toString() {
// TODO Auto-generated method stub
return "\"Company [companyName "+ companyName + ", companyTagline = " + companyTagline + ", employees = " + employees + "]";
}

}

3. Create a java class that uses Gson class to convert the Company object to Json.

package com.convertJSON;
import com.google.gson.Gson;
public class ConvertJSON {
public static Company getCompanyData(Company company) {
company.setCompanyName("Javatpoint");
company.setCompanyTagline("The Best Portal to Learn Technologies");
company.setEmployees(1000);

return company;
}
public static void main(String[] args) {
// TODO Auto-generated method stub
Company company = new Company();
company = getCompanyData(company);
System.out.println("The JSON representation of Object company is ");
System.out.println(new Gson().toJson(company));

}
}

4. We will get the JSON object upon executing the ConvertJSON class. The generated JSON string is given below.

The JSON representation of Object company is 
{
"companyName":"Javatpoint",
"companyTagline":"The Best Portal to Learn Technologies",
"employees":1000
}

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