JSON stands for JavaScript Object Notation. It’s a standard text-based format that shows structured data based on JavaScript object syntax. It is commonly used for transmitting data in web applications. JSON is highly recommended to transmit data between a server and web application. In order to convert a Java object into JSON, the following two methods can be used that are as listed below as follows:
- GSON
- JACKSON API
Java object is converted into JSON using Jackson API.
Steps to Convert Java Object to JSON String
Step 1: Add jar files of Jackson (in the case of the Maven project add Jackson dependencies in the pom.xml file)
html
<dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.5.3</version></dependency> |
Now pom.xml file is depicted below as follows:
File: Geeks/pom.xml
Step 2: Create a POJO (Plain Old Java Object) to be converted into JSON
Java
// Java Program to Illustrate Organisation Classpackage com.Geeks;// Importing required classespublic class Organisation { // Class data members private String organisation_name; private String description; private int Employees; // Calling getters and setters // Getter public String getOrganisation_name() { return organisation_name; } // Setter public void setOrganisation_name(String organisation_name) { this.organisation_name = organisation_name; } // Getter public String getDescription() { return description; } // Setter public void setDescription(String description) { this.description = description; } // Getter public int getEmployees() { return Employees; } // Setter public void setEmployees(int employees) { Employees = employees; } // Method // Creating toString @Override public String toString() { // Returning attributes of organisation return "Organisation [organisation_name=" + organisation_name + ", description=" + description + ", Employees=" + Employees + "]"; }} |
Step 3: Create a Java class for converting the Organisation object into JSON.
Convert the object into JSON using ObjectMapper class of Jackson API.
Java
// Java Program to Illustrate Object to JSON Conversionpackage com.Geeks;// Importing required classesimport com.Geeks.Organisation;import java.io.IOException;import org.codehaus.jackson.map.ObjectMapper;// Classpublic class ObjectToJson { // Main driver method public static void main(String[] a) { // Creating object of Organisation Organisation org = new Organisation(); // Insert the data into the object org = getObjectData(org); // Creating Object of ObjectMapper define in Jackson // Api ObjectMapper Obj = new ObjectMapper(); // Try block to check for exceptions try { // Getting organisation object as a json string String jsonStr = Obj.writeValueAsString(org); // Displaying JSON String on console System.out.println(jsonStr); } // Catch block to handle exceptions catch (IOException e) { // Display exception along with line number // using printStackTrace() method e.printStackTrace(); } } // Method // Getting the data to be inserted // into the object public static Organisation getObjectData(Organisation org) { // Insert the custom data org.setName("Lazyroar"); org.setDescription( "A computer Science portal for Geeks"); org.setEmployees(2000); // Returning the object return org; } |
Step 3: Execute the process.
The output in the JSON will be as below:
Output:
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