What are the differences between for, while, and do-while loops in Java?

What are the differences between for, while, and do-while loops in Java?

In Java, a 'for' loop is typically used when the number of iterations is known. A 'while' loop is used when the number of iterations is not known, and it checks the condition before executing the loop body. A 'do-while' loop is similar to a 'while' loop, but it guarantees that the loop body will execute at least once since it checks the condition after the loop body.

Can you give me an example of each loop?

Sure! Here's a simple example for each:

1. For loop:

   for (int i = 0; i < 5; i++) {
       System.out.println(i);
   }
   

2. While loop:

   int i = 0;
   while (i < 5) {
       System.out.println(i);
       i++;
   }
   

3. Do-while loop:

   int i = 0;
   do {
       System.out.println(i);
       i++;
   } while (i < 5);
   

What are the advantages of using one loop over the others?

The choice of loop depends on the situation:

• For loop is great for a known number of iterations, making it concise and easy to read.
• While loop is useful when the number of iterations is uncertain, providing flexibility.
• Do-while loop ensures the loop body executes at least once, which is beneficial when the initial condition might not be true.

Are there performance differences between these loops?

In most cases, the performance differences are negligible, as they are optimized by the Java compiler. However, the choice of loop can affect readability and maintainability, which are important for long-term performance in terms of development.