Control Statements In Java

Control statements in Java are constructs that allow you to dictate the flow of execution in your program. These include conditional statements, loop statements, and branching statements.

Control Statements in Java

1. Conditional Statements

Conditional statements allow you to execute specific blocks of code based on certain conditions.

If Statement

The if statement evaluates a boolean expression and executes the associated block of code if the expression evaluates to true.

if (condition) {
    // code to be executed if condition is true
}

If-Else Statement

The if-else statement provides an alternative block of code that executes if the condition is false.

if (condition) {
    // code to be executed if condition is true
} else {
    // code to be executed if condition is false
}

If-Else-If Ladder

The if-else-if ladder allows you to check multiple conditions sequentially.

if (condition1) {
    // code to be executed if condition1 is true
} else if (condition2) {
    // code to be executed if condition2 is true
} else {
    // code to be executed if all conditions are false
}

Switch Statement

The switch statement allows you to select one of many code blocks to be executed.

switch (expression) {
    case value1:
        // code to be executed if expression == value1
        break;
    case value2:
        // code to be executed if expression == value2
        break;
    // more cases...
    default:
        // code to be executed if expression doesn't match any case
}

2. Loop Statements

Loop statements allow you to execute a block of code multiple times.

For Loop

The for loop is used to iterate over a range of values.

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

// Example

for (int i = 0; i < 10; i++) {
    System.out.println(i);
}

While Loop

The while loop executes a block of code as long as a specified condition is true.

while (condition) {
    // code to be executed as long as condition is true
}

// Example

int i = 0;
while (i < 10) {
    System.out.println(i);
    i++;
}

Do-While Loop

The do-while loop is similar to the while loop, but it guarantees that the block of code is executed at least once.

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

// Example

int i = 0;
do {
    System.out.println(i);
    i++;
} while (i < 10);

3. Branching Statements

Branching statements allow you to change the flow of execution based on certain conditions.

Break Statement

The break statement is used to exit from a loop or a switch statement prematurely.

for (int i = 0; i < 10; i++) {
    if (i == 5) {
        break; // exits the loop when i is 5
    }
    System.out.println(i);
}

Continue Statement

The continue statement is used to skip the current iteration of a loop and proceed with the next iteration.

for (int i = 0; i < 10; i++) {
    if (i % 2 == 0) {
        continue; // skips the rest of the loop for even numbers
    }
    System.out.println(i);
}

Return Statement

The return statement is used to exit from a method and optionally return a value.

public int add(int a, int b) {
    return a + b; // returns the sum of a and b
}