How to convert JSON string to Java object?
This page shows how to convert JSON string to java object using Jackson's data binding.
Note: Refer How to convert Java object to JSON string? page for dependent libraries.
Create a simple Employee pojo. We will read JSON string from a file and map it to Employee class.
package com.java2novice.json.models;
public class Employee {
private int empId;
private String name;
private String designation;
private String department;
private int salary;
public String toString(){
StringBuilder sb = new StringBuilder();
sb.append("************************************");
sb.append("\nempId: ").append(empId);
sb.append("\nname: ").append(name);
sb.append("\ndesignation: ").append(designation);
sb.append("\ndepartment: ").append(department);
sb.append("\nsalary: ").append(salary);
sb.append("\n************************************");
return sb.toString();
}
public int getEmpId() {
return empId;
}
public void setEmpId(int empId) {
this.empId = empId;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getDesignation() {
return designation;
}
public void setDesignation(String designation) {
this.designation = designation;
}
public String getDepartment() {
return department;
}
public void setDepartment(String department) {
this.department = department;
}
public int getSalary() {
return salary;
}
public void setSalary(int salary) {
this.salary = salary;
}
}
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Finally here is the example to convert JSON string value to java object:
package com.java2novice.json.examples;
import java.io.File;
import java.io.IOException;
import org.codehaus.jackson.map.ObjectMapper;
import com.java2novice.json.models.Employee;
public class JsonToObject {
public static void main(String a[]){
ObjectMapper mapper = new ObjectMapper();
try {
File jsonInputFile = new File("C:\\jsonInput.txt");
Employee emp = mapper.readValue(jsonInputFile, Employee.class);
System.out.println(emp);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
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jsonInput.txt file contains below json input:
{
"empId": 1017,
"name": "Nagesh Y",
"designation": "Manager",
"department": "Java2Novice",
"salary": 30000
}
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