Create or Write or dump java properties to file in java (example)

Leave a Comment / By Yogesh / February 16, 2017

Given a key value pairs of properties in java.
We would like to create or write or dump java properties to the property file
We will use Properties class to set properties file.
Procedure to dump properties to property file in java.
1. Set properties using Properties class.
  - properties.setProperty(“user.name”, “admin”);
  - properties.setProperty(“user.age”, “25”);
2. We will use store method of the Properties class, to write properties object to a file.

1. Class hierarchy of Properties class in java:

Properties Hashtable class hierarchy — Fig 1: Properties class

2. Program – write or create property file in java (example)

package org.learn;
 
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Properties;
 
public class PropertyWriter {
 
    public static void main(String[] args) {
        writeProperties();
    }
 
    private static void writeProperties() {
        FileOutputStream fileOutputStream = null;
        String fileName = "output.properties";
        try {
            Properties properties = new Properties();
            properties.setProperty("user.name", "admin");
            properties.setProperty("user.age", "25");
            properties.setProperty("user.country", "USA");
            properties.setProperty("user.email", "xyz@test.com");
 
            System.out.println("1. Start writing properties to Property file");
            File writeFile = new File("output.properties");
            fileOutputStream = new FileOutputStream(writeFile);
            properties.store(fileOutputStream, "Creating new property file");
 
            System.out.println("2. Writing properties to Property file : " + properties.toString());
            System.out.printf("3. Successfully written properties to file = %s", fileName);
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (fileOutputStream != null) {
                try {
                    fileOutputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}

3. Property file in generated in work-space directory

Fig 2: Written property file in java4

4. Output – write or create property file in java (example)

Start writing properties to Property file
Writing properties to Property file : {user.name=admin, user.country=USA, user.age=25, user.email=xyz@test.com}
Successfully written properties to file = output.properties

code – dump properties or write/create property file java