Read and Write Data from Properties File in Java

The .properties is an extension in java which is used to store configurable application. It is represented by the Properties class in Java, you can store a properties file and read from it using the methods of this class. This class inherits the HashTable class.

Creating a .properties file −

To create a properties file −

• Instantiate the Properties class.

• Populate the created Properties object using the put() method.

• Instantiate the FileOutputStream class by passing the path to store the file, as a parameter.

Example

The Following Java program creates a properties file in the path D:/ExampleDirectory/

 Live Demo

import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Properties;
public class CreatingPropertiesFile {
   public static void main(String args[]) throws IOException {
      //Instantiating the properties file
      Properties props = new Properties();
      //Populating the properties file
      props.put("Device_name", "OnePlus7");
      props.put("Android_version", "9");
      props.put("Model", "GM1901");
      props.put("CPU", "Snapdragon855");
      //Instantiating the FileInputStream for output file
      String path = "D:\ExampleDirectory\myFile.properties";
      FileOutputStream outputStrem = new FileOutputStream(path);
      //Storing the properties file
      props.store(outputStrem, "This is a sample properties file");
      System.out.println("Properties file created......");
   }
}

Output

Properties file created......

If you observe the output file you can see the created contents as −

Storing properties file in XML format

You can store the properties file in XML format using the stored XML() method.

Example

 Live Demo

import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Properties;
public class CreatingPropertiesFile {
   public static void main(String args[]) throws IOException {
      //Instantiating the properties file
      Properties props = new Properties();
      //Populating the properties file
      props.put("Device_name", "OnePlus7");
      props.put("Android_version", "9");
      props.put("Model", "GM1901");
      props.put("CPU", "Snapdragon855");
      //Instantiating the FileInputStream for output file
      String outputPath = "D:\ExampleDirectory\myFile.xml";
      FileOutputStream outputStrem = new FileOutputStream(outputPath);
      //Storing the properties file in XML format
      props.storeToXML(outputStrem, "This is a sample properties file");
      System.out.println("Properties file created......");
   }
}

Output

Properties file created......