How to append data to a properties file

Hi, I have a question. I want to append data to a properties file if the properties file exists in the specified directory or else I want to create a new properties file and add data to it. Can anyone help with the complete code in Java as I am still learning  Java. Thank you.
vgsrikanthAsked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

for_yanCommented:
I believe this should work:

import java.io.*;
import java.util.Properties;

public class AppendProperties {

    public AppendProperties(){
        try{


            Properties p = new Properties();
            File f0 = new File("current.properties");
            if(f0.exists()){
                 p.load(new FileInputStream("current.properties"));
            }
            
             
            
                p.setProperty("abc","123");

                p.store(new FileOutputStream("current.properties"),"");


            




        } catch(Exception ex){
            ex.printStackTrace();
        }



    }

    public static void main(String[] args) {
        new AppendProperties();
        
    }

}

Open in new window

0
for_yanCommented:
Yes, I tested it and it works - you can run it forst time when you don't have file current.properties in your default folder - it will create it with one property abc=123

then change this line

 p.setProperty("abc","123");

to line

 p.setProperty("cde","456");

and you'll see that it added new property to the current.properties file created in the fuirst run
0
vgsrikanthAuthor Commented:
Yan, a small doubt once the file exists, I want to add something like name3=John at the end of the existing data to the properties file. The existing data is below

name1=Peter
name2=David

If the file does not exists , I want to create a new file and add name3=john to it.

Yan, can you give me the complete java code for above logic. Thank you very much.
0
Cloud Class® Course: Amazon Web Services - Basic

Are you thinking about creating an Amazon Web Services account for your business? Not sure where to start? In this course you’ll get an overview of the history of AWS and take a tour of their user interface.

for_yanCommented:
This is the complete class which does that.
If you have a file in defaule directory called "current.properties" it will
add one more propertye name3=john to those present in the file
if there is no such file it will create new file with that property:

import java.io.*;
import java.util.Properties;

public class AppendProperties {

    public AppendProperties(){
        try{


            Properties p = new Properties();
            File f0 = new File("current.properties");
            if(f0.exists()){
                 p.load(new FileInputStream("current.properties"));
            }
            
             
            
                p.setProperty("name3","john");

                p.store(new FileOutputStream("current.properties"),"");


            




        } catch(Exception ex){
            ex.printStackTrace();
        }



    }

    public static void main(String[] args) {
        new AppendProperties();
        
    }

}
                                            

Open in new window

0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
vgsrikanthAuthor Commented:
Thank you very much Yan , it worked. You are simply great.
0
for_yanCommented:
You are always welcome.
0
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Java

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.