Delete key and value from a property file?

Question

I want to delete key and value which is stored in a property file. How can i do that????

Answer 1

First load() it using the java.util.Properties API.

Properties properties = new Properties(); properties.load(reader); 

Then you can use the remove() method.

properties.remove(key); 

And finally store() it to the file.

properties.store(writer, null); 

See also:

• Properties tutorial

Answer 2

public class SolutionHash {     public static void main(String[] args) throws FileNotFoundException,IOException {         FileReader reader = new FileReader("student.properties");         Properties properties = new Properties();         properties.load(reader);         // System.out.println(properties);         Enumeration e = properties.propertyNames();         while(e.hasMoreElements()){             String key = (String)e.nextElement();             if(key.equals("dept"))                 properties.remove(key);             else                 System.out.println(key+"="+properties.getProperty(key));         }         // System.out.println(properties);     }    }  OUTPUT: name=kasinaat class=b 

Here you can see that I could remove a key value pair using remove() method.

However the remove() method is a part of the HashTable object.
It is also available in properties because properties is a subclass of HashTable