types of loop in java

Vern 51 Published: 10/03/2024

types of loop in java

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In Java, there are several types of loops that can be used to execute a block of code repeatedly for a specified number of times or until a certain condition is met. Here are some of the most common types of loops:

For Loop: The For loop is used to iterate over an array or collection of objects. It has three main components: initialization, condition, and increment.

Example:

for (int i = 0; i < 5; i++) {
System.out.println("Hello, world! " + i);
}

While Loop: The While loop is used to repeat a block of code as long as a certain condition is true. It has two main components: condition and body.

Example:

int i = 0;
while (i < 5) {
System.out.println("Hello, world! " + i);
i++;
}

Do-While Loop: The Do-While loop is similar to the While loop, but it checks the condition after executing the body.

Example:

int i = 0;
do {
System.out.println("Hello, world! " + i);
i++;
} while (i < 5);

For-Each Loop: The For-Each loop is used to iterate over a collection of objects using an iterator.

Example:

List names = Arrays.asList("John", "Mary", "David");
for (String name : names) {
System.out.println(name);
}

Enhanced For Loop: The Enhanced For loop is similar to the For-Each loop, but it can be used with primitive types and arrays.

Example:

int[] numbers = {1, 2, 3, 4, 5};
for (int num : numbers) {
System.out.println(num);
}

Infinite Loop: An infinite loop is a loop that has no terminating condition, so it will continue to run indefinitely.

Example:

while (true) {
// code here
}

Break and Continue Statements: The Break statement is used to exit the loop immediately, while the Continue statement is used to skip the current iteration of the loop and move on to the next one.

Example:

for (int i = 0; i < 5; i++) {
if (i == 3) {
break;
}
System.out.println("Hello, world! " + i);
}

In summary, Java has a variety of loop types that can be used to execute code repeatedly. By choosing the right type of loop for your specific problem, you can write more efficient and effective code.

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Java loops w3schools

Here's an explanation of Java loops with examples from W3Schools:

Java has several types of loops that can be used to execute a block of code repeatedly. These include:

For Loop: The for loop is used when you need to iterate over an array or a collection of items.

Example:

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

This will print out the numbers 0 through 4 with the string "Hello" preceding each number.

W3Schools Example:

For Loop

This will create a webpage that prints out the items in the fruits array.

While Loop: The while loop is used when you need to repeat a block of code as long as a certain condition is true.

Example:

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

This will print out the numbers 0 through 4 with the string "Hello" preceding each number, just like the for loop example.

W3Schools Example:

While Loop

This will create a webpage that prints out the numbers 0 through 4 with the string "Hello" preceding each number.

Do-While Loop: The do-while loop is used when you want to execute a block of code at least once, and then repeat it as long as a certain condition is true.

Example:

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

This will print out the numbers 0 through 4 with the string "Hello" preceding each number, just like the for loop example.

W3Schools Example:

Do-While Loop

This will create a webpage that prints out the numbers 0 through 4 with the string "Hello" preceding each number.

Infinite Loop: An infinite loop is a loop that runs indefinitely, unless it is interrupted by an break or return statement.

Example:

while (true) {
System.out.println("Hello");
}

This will print out the string "Hello" indefinitely, until the program is stopped.

W3Schools Example:

Infinite Loop

This will create a webpage that prints out the string "Hello" indefinitely, until the program is stopped.

In conclusion, Java has several types of loops that can be used to execute a block of code repeatedly. Each type of loop serves a specific purpose and can be used in different situations.