Convert Java Object to Json String using Jackson API
JSON Stand for JavaScript Object Notation. It’s a standard text-based format which 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.
To convert a Java object into JSON, the following methods can be used:
- GSON
- JACKSON API
In this article, Java object is converted into the JSON using Jackson API:
The steps to do this are as follows:
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- Add jar files of Jackson (in case of Maven project add Jackson dependencies in pom.xml file)
html
<dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.5.3</version></dependency> |
- Below is the screenshot showing this step:
- Create a POJO (Plain Old Java Object) to be converted into JSON
Java Class
Java
package com.Geeks;public class Organisation { private String organisation_name; private String description; private int Employees; // Calling getters and setters public String getOrganisation_name() { return organisation_name; } public void setOrganisation_name(String organisation_name) { this.organisation_name = organisation_name; } public String getDescription() { return description; } public void setDescription(String description) { this.description = description; } public int getEmployees() { return Employees; } public void setEmployees(int employees) { Employees = employees; } // Creating toString @Override public String toString() { return "Organisation [organisation_name=" + organisation_name + ", description=" + description + ", Employees=" + Employees + "]"; }} |
- Below is the screenshot showing this step:
- Create a Java class for converting the Organisation object into JSON. Convert the object into JSON using ObjectMapper class of Jackson API.
Java
package com.Geeks;import java.io.IOException;import org.codehaus.jackson.map.ObjectMapper;import com.Geeks.Organisation;public class ObjectToJson { 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 Jakson Api ObjectMapper Obj = new ObjectMapper(); try { // get Oraganisation object as a json string String jsonStr = Obj.writeValueAsString(org); // Displaying JSON String System.out.println(jsonStr); } catch (IOException e) { e.printStackTrace(); } } // Get the data to be inserted into the object public static Organisation getObjectData(Organisation org) { // Insert the data org.setName("GeeksforGeeks"); org.setDescription("A computer Science portal for Geeks"); org.setEmployees(2000); // Return the object return org; } |
- Execute the process.
- The output in the JSON will be as below:
Output
{
"organisation_name" : "GeeksforGeeks",
"description" : "A computer Science portal for Geeks",
"Employee" : "2000"
}
- Below is the screenshot showing this output:
