Java SE 8 Programmer II Sample Test Questions
1. Which control flow statement allows you to repeat a block of code a specific number of times based on a counter variable?
a) if b) while c) for d) switch
Answer: c) for
Explanation: The for loop is specifically designed for iterating a block of code a predetermined number of times. It uses a counter variable that is initialized, incremented/decremented, and compared with a condition to control the number of repetitions.
Code Example:
for (int i = 1; i <= 5; i++) {
System.out.println("Iteration " + i);
}
This code will print "Iteration 1" to "Iteration 5" on the console.
2. Which control flow statement allows you to repeat a block of code indefinitely as long as a condition remains true?
a) if b) while c) for d) switch
Answer: b) while
Explanation: The while loop repeatedly executes a block of code as long as the specified condition evaluates to true. It checks the condition before each iteration, allowing for indefinite repetition until the condition becomes false.
Code Example:
int num = 10;
while (num > 0) {
System.out.println(num);
num--;
}
This code will print numbers from 10 to 1 on the console, decrementing num in each iteration.
. Which control flow statement allows you to choose between different code blocks based on the value of a variable?
a) if b) while c) for d) switch
Answer: a) if
Explanation: The if statement evaluates a condition and executes a specific block of code if the condition is true. It can also have an optional else block to execute code if the condition is false.
Code Example:
int age = 20;
if (age >= 18) {
System.out.println("You are eligible to vote.");
} else {
System.out.println("You are not eligible to vote.");
}
This code checks if the user's age is 18 or more and prints a corresponding message.
4. Which control flow statement allows you to choose between multiple code blocks based on the value of a variable, using a more concise syntax compared to multiple if-else statements?
a) if b) while c) for d) switch
Answer: d) switch
Explanation: The switch statement is used to select a specific block of code based on the value of a variable. It uses case labels to match different values and provides a more efficient way to handle multiple choices.
Code Example:
String day = "Monday";
switch (day) {
case "Monday":
System.out.println("It's a workday!");
break;
case "Saturday":
case "Sunday":
System.out.println("It's the weekend!");
break;
default:
System.out.println("Invalid day");
}
This code checks the day of the week and prints a corresponding message.
5. Which control flow statement allows you to skip the current iteration of a loop and jump to the next iteration?
a) if b) while c) for d) continue
Answer: d) continue
Explanation: The continue statement skips the remaining code in the current iteration of a loop and immediately jumps to the next iteration. It's useful for conditionally skipping certain iterations within a loop.
Code Example:
for (int i = 1; i <= 10; i++) {
if (i % 2 == 0) {
continue; // Skip even numbers
}
System.out.println(i);
}
This code prints only odd numbers from 1 to 10.