In this post, you will learn how to read properties file in Java project.
Introduction
- In Java property file is a special file, which contains key-value pairs.
- Java has provided
Properties
class injava.util
package, which provides a way to read the property file values.
Step 1 – Create a property file
Inside the Java project, create a file app.properties
inside the src
folder. You can give any name to the file but property file should have a extension .properties
. Open the file and add the following contents
app.name=Read properties file
app.version=1.0
As you can see, the file contains two properties app.name
and app.version
Step 2 – Create a Java file
Inside the src
folder, create a java file ReadProperties.java
and add the following content
import java.io.FileInputStream;
import java.io.IOException;
import java.util.Properties;
public class ReadProperties {
public static void main(String[] args) throws IOException{
String filePath = "C:\\Users\\bushan\\Documents\\workspace-sts-3.9.10.RELEASE\\Java-tutorial\\src\\app.properties";
Properties prop = new Properties();
FileInputStream fs = new FileInputStream(filePath);
prop.load(fs);
System.out.println(prop.getProperty("app.name"));
System.out.println(prop.getProperty("app.version"));
}
}
First, we are creating an object of Properties
class
Properties prop = new Properties();
Next, we are creating an object of FileInputStream
class to read the file
FileInputStream fs = new FileInputStream(filePath);
Next, we are loading the file using load()
of Properties class
prop.load(fs);
Once we load the property file, then we can read the property values using getProperty()
, this takes property name as a parameter.
System.out.println(prop.getProperty("app.name"));