What are loops in Java? How to use for loop and while loop?

1. The for Loop: Predetermined Repetition

• Structure:
  Java

  for (initialization; condition; update) {
    // code to repeat
  }

• Perfect for: Known number of iterations
• Example: Printing numbers 1 to 5
  Java

  for (int i = 1; i <= 5; i++) {
    System.out.println(i);
  }

2. The while Loop: Repetition Based on Conditions

• Structure:
  Java

  while (condition) {
    // code to repeat
  
  

• Ideal for: Uncertain or runtime-dependent iterations
• Example: User input until "quit"
  Java

  Scanner scanner = new Scanner(System.in);
  String input;
  while (!(input = scanner.nextLine()).equalsIgnoreCase("quit")) {
    // process input
  }

Key Differences to Remember:

• Initialization: for initializes within the loop; while needs it outside.
• Condition Checking: for has it within the declaration; while checks explicitly.
• Use Cases: for for known iterations; while for runtime-determined ones.

Additional Control for Flexibility:

• break: Exits a loop prematurely.
• continue: Skips to the next iteration.

Common Applications:

• Iterating through arrays, lists, and collections.
• Implementing game loops or user input loops.
• Processing data until a specific condition is met.

Caution: Beware of infinite loops! Always ensure loop conditions eventually become false.

By understanding and applying loops effectively, you'll write more concise, elegant, and efficient Java code, capable of mastering repetitive tasks with ease. Embrace the power of loops to streamline your programs and create robust, adaptable applications!