Loops In Java
Hey there! In this guide, we'll explore loops in Java. Loops are used to execute a block of code repeatedly based on specific conditions. Let's dive in!
- Java provides several types of loops that allow you to execute a block of code multiple times based on specific conditions.
- The main types of loops in Java are
for
,while
, anddo-while
.
1. For Loop​
The for loop is used when you know how many times you want to execute a statement or a block of statements.
Syntax:​
for (initialization; condition; increment/decrement) {
// code to be executed
}
Example:​
public class Main {
public static void main(String[] args) {
for (int i = 0; i < 5; i++) {
System.out.println("Iteration " + i);
}
}
}
Output:​
Iteration 0
Iteration 1
Iteration 2
Iteration 3
Iteration 4
2. While Loop​
The while
loop is used when you want to execute a block of code as long as a specified condition is true.
Syntax:​
while(condition) {
// code to be executed
}
Example:​
public class Main {
public static void main(String[] args) {
int i = 0;
while (i < 5) {
System.out.println("Iteration " + i);
i++;
}
}
}
}
Output:​
Iteration 0
Iteration 1
Iteration 2
Iteration 3
Iteration 4
3. Do-While Loop​
The do-while
loop is similar to the while
loop, except that it guarantees that the code block will be executed at least once before the condition is tested.
Syntax:​
do {
// code to be executed
} while(condition);
Example:​
public class Main {
public static void main(String[] args) {
int i = 0;
do {
System.out.println("Iteration " + i);
i++;
} while (i < 5);
}
}
Output:​
Iteration 0
Iteration 1
Iteration 2
Iteration 3
Iteration 4
4. Nested Loops​
You can also use loops inside other loops, which are called nested loops.
Example:​
public class Main {
public static void main(String[] args) {
for (int i = 1; i <= 3; i++) {
for (int j = 1; j <= 2; j++) {
System.out.println("Outer Loop: " + i + ", Inner Loop: " + j);
}
}
}
}
Outer Loop: 1, Inner Loop: 1
Outer Loop: 1, Inner Loop: 2
Outer Loop: 2, Inner Loop: 1
Outer Loop: 2, Inner Loop: 2
Outer Loop: 3, Inner Loop: 1
Outer Loop: 3, Inner Loop: 2
5. Break and Continue Statements​
a. Break Statement​
The break
statement is used to exit a loop prematurely.
Example:​
public class Main {
public static void main(String[] args) {
for (int i = 0; i < 10; i++) {
if (i == 5) {
break; // Exit the loop when i equals 5
}
System.out.println("Iteration " + i);
}
}
}
Output:​
Iteration 0
Iteration 1
Iteration 2
Iteration 3
Iteration 4
b. Continue Statement​
The continue
statement skips the current iteration and proceeds to the next one.
Example:​
public class Main {
public static void main(String[] args) {
for (int i = 0; i < 5; i++) {
if (i == 2) {
continue; // Skip the iteration when i equals 2
}
System.out.println("Iteration " + i);
}
}
}
Output:​
Iteration 0
Iteration 1
Iteration 2
Iteration 3
Iteration 4
Loops are essential for controlling the flow of execution in your Java programs, enabling you to perform repetitive tasks efficiently. Understanding how to use them effectively will greatly enhance your programming skills!