I have trouble with changing my code. I want to do that with a boolean and I have no clue how to do that. It is just confusing me.
This is my task:
Tyrepressure-test
It is to check whether the pressure of all tires is between 35 and 45. If a tire is outside this range, a warning message is issued immediately. After that, the program continues reading and processing the values.
If a warning message occurs, the program issues a final warning message at the end. We declare a Boolean variable pressureOK for this purpose.
boolean pressureOK
We initialize it with true and set the value to false if a tire is outside the valid range.
They’re even helping me in the task with the boolean thing but I’m so clueless and confused so that I just don’t know how to do that. To be honest I have tried literally everything. Before I ask for a solution I always try everything that is possible because if I would just ask for a solution without trying it, it would be useless.
my code:
import java.util.Scanner;
public class Tyrepressure {
public static void main(String[] args) {
Scanner scanner1 = new Scanner(System.in);
System.out.println("Enter your tyrepressure of your right-front-tyre in pounds per square inch: ");
double rightFrontTyre = scanner1.nextDouble();
System.out.println(" "); // For space in between the user input
System.out.println("Enter your tyrepressure of your left-front-tyre in pounds per square inch: ");
double leftFrontTyre = scanner1.nextDouble();
System.out.println(" "); // For space in between the user input
System.out.println("Enter your tyrepressure of your left-back-tyre in pounds per square inch: ");
double rightBackTyre = scanner1.nextDouble();
System.out.println(" "); // For space in between the user input
System.out.println("Enter your tyrepressure of your right-back-tyre in pounds per square inch: ");
double leftBackTyre = scanner1.nextDouble();
System.out.println(" "); // For space in between the user input
if (rightFrontTyre >= 35 && rightFrontTyre <= 45) {
System.out.println("right-front-tyre = " + rightFrontTyre + " psi, your tyrepressure is okay!");
} else {
System.out.println("right-front-tyre = " + rightFrontTyre
+ " psi, your tyrepressure is critical, it is out of the allowed range!");
}
System.out.println(" "); // For space in between the user input
if (leftFrontTyre >= 35 && leftFrontTyre <= 45) {
System.out.println("left-front-tyre = " + leftFrontTyre + " psi, your tyrepressure is okay!");
} else {
System.out.println("left-front-tyre = " + leftFrontTyre
+ " psi, your tyrepressure is critical, it is out of the allowed range!");
}
System.out.println(" "); // For space in between the user input
if (rightBackTyre >= 35 && rightBackTyre <= 45) {
System.out.println("right-back-tyre = " + rightBackTyre + " psi, your tyrepressure is okay!");
} else {
System.out.println("right-back-tyre = " + rightBackTyre
+ " psi, your tyrepressure is critical, it is out of the allowed range!");
}
System.out.println(" "); // For space in between the user input
if (leftBackTyre >= 35 && leftBackTyre <= 45) {
System.out.println("left-back-tyre = " + leftBackTyre + " psi, your tyrepressure is okay!");
} else {
System.out.println("left-back-tyre = " + leftBackTyre
+ " psi, your tyrepressure is critical, it is out of the allowed range!");
}
System.out.println(" "); // For space in between the user input
if (rightFrontTyre < 35 || rightFrontTyre > 45 || leftFrontTyre < 35 || leftFrontTyre > 45
|| rightBackTyre < 35 || rightBackTyre > 45 || leftBackTyre < 35 || leftBackTyre > 45) {
System.out.println("You have to check your tyrepressure!");
}
}
}
output:
Enter your tyrepressure of your right-front-tyre in pounds per square inch:
40
Enter your tyrepressure of your left-front-tyre in pounds per square inch:
32
Enter your tyrepressure of your left-back-tyre in pounds per square inch:
11
Enter your tyrepressure of your right-back-tyre in pounds per square inch:
40
right-front-tyre = 40.0 psi, your tyrepressure is okay!
left-front-tyre = 32.0 psi, your tyrepressure is critical, it is out of the allowed range!
right-back-tyre = 11.0 psi, your tyrepressure is critical, it is out of the allowed range!
left-back-tyre = 40.0 psi, your tyrepressure is okay!
You have to check your tyrepressure!
It works fine but I have to do the last part with a boolean datatype and as I already said I just don’t know how…..
>Solution :
You can assign the expression inside the condition in the if statement – and then reuse that in the if, like so:
boolean pressureOkRightFront = (rightFrontTyre >= 35 && rightFrontTyre <= 45);
if (pressureOkRightFront) {
System.out.println("right-front-tyre = " + rightFrontTyre + " psi, your tyrepressure is okay!");
} else {
System.out.println("right-front-tyre = " + rightFrontTyre
+ " psi, your tyrepressure is critical, it is out of the allowed range!");
}
boolean pressureOkLeftFront = (leftFrontTyre >= 35 && leftFrontTyre <= 45);
// continue with the code for the other three tyres - remember to use a new boolean variable for each.
// then do this for the final check:
if (!(pressureOkRightFront && pressureOkLeftFront &&
pressureOkRightBack && pressureOkLeftBack)) {
System.out.println("You have to check your tyrepressure!");
}
Please note that in your original code you checked the opposite conditions for the last output – if any of the pressures is out of range. I used boolean logic to get the same final result from the single prechecked results for the individual tyres:
If NOT all of the four pressures are OK, I print the warning. The NOT is the exclamation mark ! in that condition, and the parentheses are important because otherwise the ! would be evaluated only for the pressureOkRightFront.