Loop in Java Programming

Loops are control structures that enable you to iterate over a block of code until a certain condition is met. They eliminate the need for writing repetitive code, making programs more efficient and concise. Loops play a vital role in handling collections of data, performing calculations, and implementing iterative algorithms.

Types of Loops in Java

Java provides three main types of loops: the for loop, the while loop, and the do-while loop. Each loop type has its own specific use cases and syntax. Let's explore each type in detail.

for Loop

The for loop is a compact and powerful construct for iteration. It consists of three parts: initialization, condition, and iteration expression. The loop continues until the condition evaluates to false.

for (initialization; condition; iteration) {
    // code to be executed
}

public class ForLoopSmallCode {
    public static void main(String[] args) {
        for (int i = 1; i <= 5; i++) {
            System.out.println("Iteration: " + i);
        }
    }
}

while Loop

The while loop repeatedly executes a block of code as long as the specified condition is true. The condition is evaluated before entering the loop body.

while (condition) {
    // code to be executed
    // iteration or condition update
}

public class WhileLoopSmallCode {
    public static void main(String[] args) {
        int count = 1;
        while (count <= 5) {
            System.out.println("Count: " + count);
            count++;
        }
    }
}

do-while Loop

The do-while loop is similar to the while loop, but the condition is evaluated after executing the loop body. This guarantees that the loop body is executed at least once.

do {
    // code to be executed
    // iteration or condition update
} while (condition);

public class DoWhileLoopSmallCode {
    public static void main(String[] args) {
        int num = 1;

        do {
            System.out.println("Number: " + num);
            num++;
        } while (num <= 5);
    }
}

Loops are indispensable tools in Java programming, providing the ability to repeat code execution based on specific conditions. The for loop is suitable for iterating over a known number of times, while the while and do-while loops are more flexible when the exact number of iterations is unknown.