Control Flow Statements in Java

How Control Flow Statements Work in Java
Control flow statements in Java involve how a program executes specific blocks of code. They help to make decisions, repeat tasks and more effective program flow. This guide explains these statements simply and clearly for beginners and even that person's wet between the ears again.
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These Are Control Flow Statements
Control flow statements control the order in which the instructions of a program are to be executed. They are mainly classified into three categories:
1. Decision Making Statements – if, if-else, switch
2. Looping Statements – for, while, do-while
3. Branching Statements – break, continue, return
Let us discover the different types with example.
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1. Decision Making Statements
The statements that allow the program to choose what block of code to execute on the basis of some conditions.
1.1 if Statement
The if statement checks a certain condition and runs the code inside only if the condition is true.
int num = 10;
if (num > 0) {
System.out.println("The number is positive.");
}
1.2 if, else Statement
It gives two alternatives either when the condition is true and when it is false.
int num = -5;
if (num > 0) {
System.out.println("Positive number");
} else {
System.out.println("Negative number");
}
1.3 if-else-if Ladder
When checking more than one condition.
int num = 0;
if (num > 0) {
System.out.println("Positive number");
} else if (num < 0) {
System.out.println("Negative number");
} else {
System.out.println("Zero");
}
1.4 switch statements
The switch checks a variable against multiple values and executes the matching block.
int day = 3;
switch (day) {
case 1:
System.out.println("Monday");
break;
case 2:
System.out.println("Tuesday");
break;
case 3:
System.out.println("Wednesday");
break;
default:
System.out.println("Invalid day");
}
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2. Loops Statement
Continually repeat a set of instructions.
2.1 for a Loop
For cases where the number of repetitions is evident at the start.
for (int i = 1; i <= 5; i++) {
System.out.println("Iteration: " + i);
}
2.2 while Loop
Keep executing the block of code a number of times as long as the condition is satisfied.
int i = 1;
while (i <= 5) {
System.out.println("Iteration: " + i);
i++;
}
2.3 do-while Loop
It executes at least once, checks the condition then continues.
int i = 1;
do {
System.out.println("Iteration: " + i);
i++;
} while (i <= 5);
For further concepts on Java control flow, refer to Java Control Flow Statements and Operators Interview FAQs
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3. Branching Statements
Branching statements affect the flow of a loop or switch case.
3.1 break Statement
It exits the loop or switch case immediately.
for (int i = 1; i <= 5; i++) {
if (i == 3) {
break;
}
System.out.println("Iteration: " + i);
}
3.2 continue Statement
It skips the current iteration and forwards to the next.
for (int i = 1; i <= 5; i++) {
if (i == 3) {
continue;
}
System.out.println("Iteration: " + i);
}
3.3 return Statement
Used to exit a method and return a value.
public class Example {
public static int square(int num) {
return num * num;
}
public static void main(String[] args) {
System.out.println("Square of 4: " + square(4));
}
}
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Conclusion

Control flow statements are important for developing flexible and efficient Java programs. Decision making statements like if and switch control the logic of the program. Looping statements (for, while, do-while) help to realize repeated execution. Branching statements (break, continue, return) enhance management of loops and functions.