For loop blank condition

Question

The condition in the for loop is left blank and the code compiles and runs.

 for(int i=0; ; i++)
    System.out.print(i);  //this code does not execute
 //code after this does not execute

But, I don't understand how and why this is possible.

Answer 1

Just change below line, although its not an issue.

System.out.print(i);  //this code does not seems execute by checking o/p on console but in reals it works as well.

To

System.out.println(i);  //this code works and you will be able to see o/p on console.

OR

System.out.print(i+" "); // this will show you some momentary action on Eclipse console.

It seems to me as some Eclipse IDE console printing issue. With the first version as you mentioned in your question, I can't see any output. As print() keeps on printing on the same line may be its not visible to us.

However, if you run your code in Debug mode and place a breakpoint on the above line. Breakpoint will hit and you can see the output being printed as well.

But for the second version, I can see it printing all number starting from 0,1...

This is a similar discussion as shared by @PakkuDon

Answer 2

If it prints nothing, it means you're not reaching this for loop at all.
If you're reaching it, it should print all numbers from 0 going up.
This is an endless loop printing 0, 1, 2, ...
Your problem is elsewhere (probably before the for loop).