Develop Reference

How can I print something based on the result of a boolean method?

I have two methods
*`public boolean validateMarks() {
return (this.qualifyingMarks >= 65 && this.qualifyingMarks <= 100);
}
public boolean validateCourseId() {
return (this.courseId >= 1001 && this.courseId <= 1005);
}`*
validateMarks(): Used to validate qualifying exam marks - qualifying marks is in the range of 65 to 100(both inclusive)
validateCourseId(): Used to validate the course entered, based on the courseId - given in the table above
calculateCourseFee(): Used to calculate the course fee after applying the discount.
So when is less than 65 print print "not elegible, you've failed" and when the course is not valid "course is not correct, please try again with the correct number of the course"
and this is my calculateCourseFee method
***if(this.validateMarks()) {
this.courseFee = fee - (fee * discount);
System.out.println("****Course Allocation Details****" + "\n" +
"Student Name: " + this.getStudentName() + "\n" +
"Course Id: " + this.getCourseId() + "\n" +
"Qualifying Exam Marks: " + this.getQualifyingMarks() + "\n" +
"Student's Registration Id: " + this.getRegistrationId() + "\n" +
"Total Course Fee: " + this.getCourseFee() + "\n" +
"Hostel Required: " + hostel);
}else {
System.out.println("wrong for marks ");
}
if(this.validateCourseId()) {
this.courseFee = fee - (fee * discount);
System.out.println("****Course Allocation Details****" + "\n" +
"Student Name: " + this.getStudentName() + "\n" +
"Course Id: " + this.getCourseId() + "\n" +
"Qualifying Exam Marks: " + this.getQualifyingMarks() + "\n" +
"Student's Registration Id: " + this.getRegistrationId() + "\n" +
"Total Course Fee: " + this.getCourseFee() + "\n" +
"Hostel Required: " + hostel);
}else {
System.out.println("Wroog for course");
}
***
I make two different ifs for the two requirements, but everytime I run it, it prints the else statement to, even if marks is greather than 65... am I missing something?
Reviewing my code and tell me what am I missing or what am I doing wrong

The portion of the code you have shown here seems to be working as expected.
public class Driver {
public static void main(String args[]) {
Eligible e1 = new Eligible();
e1.calculateCourseFee();
}
}
class Eligible{
int qualifyingMarks = 66;
int courseId = 1002;
public boolean validateMarks() {
return (this.qualifyingMarks >= 65 && this.qualifyingMarks <= 100);
}
public boolean validateCourseId() {
return (this.courseId >= 1001 && this.courseId <= 1005);
}
public void calculateCourseFee(){
if(this.validateMarks()) {
System.out.println("works for marks");
}else {
System.out.println("wrong for marks ");
}
if(this.validateCourseId()) {
System.out.println("works for course");
}else {
System.out.println("Wroog for course");
}
}
}
output:
works for marks
works for course
Maybe the issues is with how you set the values for the qualifyingMarks and courseId variables?

I wish I could give you a like or thumbs up, I finally did it, thanks to all of your answers you gave me, and I just combined the two ifs into one. here's the code:
if(this.validateCourseId() && this.validateMarks()) {
this.courseFee = fee - (fee * discount);
System.out.println("****Course Allocation Details****" + "\n" +
"Student Name: " + this.getStudentName() + "\n" +
"Course Id: " + this.getCourseId() + "\n" +
"Qualifying Exam Marks: " + this.getQualifyingMarks() + "\n" +
"Student's Registration Id: " + this.getRegistrationId() + "\n" +
"Total Course Fee: " + this.getCourseFee() + "\n" +
"Hostel Required: " + hostel);
}else if(!this.validateCourseId()) {
System.out.println("Wrong course");
}
else if(!this.validateMarks()) {
System.out.println("You've failed");
}
Thanks everyone!!

maybe qualifyingMarks is zero or another value, print qualifyingMarks in method "validateMarks",u will get the reason of your problem.

Java error handling for project- Line matched except underscores: Invalid Event Code_?

I completed this java project for a class, but I cannot seem to fix the error I'm getting for the web software that grades it- it's called webcat. I've tried the test input the software suggests for a reference test against my solution, and my output looks exactly the same, but I still lost points for this error-
"Error in method main of class Event: Line number 2 of your output is incorrect (line numbers begin at 1). Your main method does not print the correct output when the input is "This is a short test " (input less than 26 characters) [] Line matched except underscores: Invalid Event Code_".
How can I fix this error when the expected ouput looks fine? Thanks in advance!
Code:
public class Event {
/**
* accepts coded event info, prints the info back to std output, and
actual cost and prize number.
*
* #param args Command line arguments - not used.
*/
public static void main(String[] args) {
// variables needed
String shrink, event, date, time, section, row, seat;
double price, discount, cost;
int prizeNum;
// accept input
Scanner userInput = new Scanner(System.in);
// format the numbers
DecimalFormat formatNum = new DecimalFormat("$#,##0.00");
// enter input and trim the space
System.out.print("Enter your event code: ");
shrink = userInput.nextLine().trim();
if (shrink.length() < 26) {
System.out.println();
System.out.println("Invalid Event Code");
System.out.println("Event code must have at least 26 characters.");
return;
}
// locates spot in index of code and assigns
event = shrink.substring(25, shrink.length());
date = shrink.substring(0, 8);
time = shrink.substring(8, 12);
section = shrink.substring(19, 21);
row = shrink.substring(21, 23);
seat = shrink.substring(23, 25);
price = Double.parseDouble(shrink.substring(12, 15)
+ "." + shrink.substring(15, 17));
discount = Double.parseDouble(shrink.substring(17, 19));
// calculates final cost
cost = price - (price * (discount / 100));
// random final number
prizeNum = (int) (Math.random() * 1000 + 1);
// prints the data to std output
System.out.println();
System.out.print("Event: " + event + " " + " " + " ");
System.out.print("Date: " + date.substring(0, 2) + "/"
+ date.substring(2, 4) + "/" + date.substring(4, 8) + " "
+ " " + " ");
System.out.println("Time: " + time.substring(0, 2) + ":"
+ time.substring(2, 4) + " " + " " + " ");
System.out.print("Section: " + section + " " + " " + " ");
System.out.print("Row: " + row + " " + " " + " ");
System.out.println("Seat: " + seat);
System.out.print("Price: " + formatNum.format(price) + " " + " " + " ");
// formats discount before print
formatNum.applyPattern("#.#'%'");
System.out.print("Discount: " + formatNum.format(discount) + " "
+ " " + " ");
// formats cost before print
formatNum.applyPattern("$#,##0.00");
System.out.println("Cost: " + formatNum.format(cost));
System.out.print("Prize Number: " + prizeNum);
Output:
Enter your event code: This is a short test
Invalid Event Code
Event code must have at least 26 characters.

Storing Statistics in Java Calculator

Having difficulty storing the following statistics to be printed when the program terminates. I have been able to store the total number of valid and invalid expressions however I am having difficulty with the following:
The highest overall result value.
The lowest overall result value.
The aggregate of all result values, i.e. all results added together.
The average result value
Any guidance for any of the above would be much appreciated.
Scanner input = new Scanner(System.in); // Creating new scanner to take user choice input
int validExpressions = 0;
int invalidExpressions = 0;
int lowestval = 0;
int highestval;
while (true) {
System.out.println("Enter K to enter a postfix expression or F to open a text file:"); // requesting user input
String choice = input.nextLine(); // Taking user input from keyboard, either K for manual entry or F for file input
float answer; // Variable used to store answers.
if ("F".equals(choice)) {
System.out.println("Please enter the name of a .txt file:"); // user prompted to enter the name of the text file
String file = input.nextLine(); // File name will be stored in a String (file) to be used later
File txtfile = new File(file);
Scanner reader = new Scanner(txtfile); // Creating a new scanner which reads the text file
while (reader.hasNextLine()) { // The new scanner (reader) reads each line of the text file
String expression = reader.nextLine(); // Each line is stored in a String called Expression
String[] parts = expression.split(" "); // The string is split into three parts; two numbers and an operator
String part1 = parts[0];
String part2 = parts[1];
String part3 = parts[2];
float number1 = Float.parseFloat(part1); // Parts one and two are both converted from a String to a Float
float number2 = Float.parseFloat(part2);
// Program processes the operator and applies it to Float number1 and Float number2 before outputting the
// expression and the correct answer
if ("+".equals(part3)) {
answer = number1 + number2;
System.out.println(part1 + " " + "+" + " " + part2 + " " + "=" + " " + answer);
validExpressions++;
} else if ("-".equals(part3)) {
answer = number1 - number2;
System.out.println(part1 + " " + "-" + " " + part2 + " " + "=" + " " + answer);
validExpressions++;
} else if ("*".equals(part3)) {
answer = number1 * number2;
System.out.println(part1 + " " + "*" + " " + part2 + " " + "=" + " " + answer);
validExpressions++;
} else if ("/".equals(part3)) {
answer = number1 / number2;
System.out.println(part1 + " " + "/" + " " + part2 + " " + "=" + " " + answer);
validExpressions++;
}
}
} else if ("K".equals(choice)) // If the user enters K input will be taken from the keyboard
System.out.println("Please enter a post-fix expression:"); // User is prompted to enter a post fix expression
Scanner expression = new Scanner(System.in); // Creating a new Scanner called Expression to read user input
String exp = expression.nextLine(); // The user's input is stored in a string
String[] elements = exp.split(" "); // Expression is split into three elements, two numbers and an operator
String element1 = elements[0];
String element2 = elements[1];
String element3 = elements[2];
float num1 = Float.parseFloat(element1); // Element1 and element2 are converted to Floats and named num1 and num2
float num2 = Float.parseFloat(element2);
// Program processes the operator and applies it to Float num1 and Float num2 before outputting the
// expression and the correct answer
if ("+".equals(element3)) {
answer = num1 + num2;
System.out.println(element1 + " " + "+" + " " + element2 + " " + "=" + " " + answer);
validExpressions++;
} else if ("-".equals(element3)) {
answer = num1 - num2;
System.out.println(element1 + " " + "-" + " " + element2 + " " + "=" + " " + answer);
validExpressions++;
} else if ("*".equals(element3)) {
answer = num1 * num2;
System.out.println(element1 + " " + "*" + " " + element2 + " " + "=" + " " + answer);
validExpressions++;
} else if ("/".equals(element3)) {
answer = num1 / num2;
System.out.println(element1 + " " + "/" + " " + element2 + " " + "=" + " " + answer);
validExpressions++;
if (choice.isEmpty()) { // If the user does not enter K or F the program will exit
System.out.println("Evaluations Complete");
System.out.println("-------------------------");
System.out.println("Valid expressions: " + validExpressions);
System.out.println("Invalid expressions: " + invalidExpressions);
System.exit(0);
}
}
}
}
}

I have changed something wrong on logic and syntax，but I have not debuged it ,you may have a try.
Scanner input = new Scanner(System.in); // Creating new scanner to take user choice input
int validExpressions = 0;
int invalidExpressions = 0;
float lowestval = 0;
float highestval =0 ;
float total=0;
while (true) {
System.out.println("Enter K to enter a postfix expression or F to open a text file:"); // requesting user input
String choice = input.nextLine(); // Taking user input from keyboard, either K for manual entry or F for file input
float answer; // Variable used to store answers.
if ("F".equals(choice)) {
System.out.println("Please enter the name of a .txt file:"); // user prompted to enter the name of the text file
String file = input.nextLine(); // File name will be stored in a String (file) to be used later
File txtfile = new File(file);
Scanner reader = new Scanner(txtfile); // Creating a new scanner which reads the text file
while (reader.hasNextLine()) { // The new scanner (reader) reads each line of the text file
String expression = reader.nextLine(); // Each line is stored in a String called Expression
String[] parts = expression.split(" "); // The string is split into three parts; two numbers and an operator
String part1 = parts[0];
String part2 = parts[1];
String part3 = parts[2];
float number1 = Float.parseFloat(part1); // Parts one and two are both converted from a String to a Float
float number2 = Float.parseFloat(part2);
// Program processes the operator and applies it to Float number1 and Float number2 before outputting the
// expression and the correct answer
if ("+".equals(part3)) {
answer = number1 + number2;
System.out.println(part1 + " " + "+" + " " + part2 + " " + "=" + " " + answer);
validExpressions++;
} else if ("-".equals(part3)) {
answer = number1 - number2;
System.out.println(part1 + " " + "-" + " " + part2 + " " + "=" + " " + answer);
validExpressions++;
} else if ("*".equals(part3)) {
answer = number1 * number2;
System.out.println(part1 + " " + "*" + " " + part2 + " " + "=" + " " + answer);
validExpressions++;
} else if ("/".equals(part3)) {
answer = number1 / number2;
System.out.println(part1 + " " + "/" + " " + part2 + " " + "=" + " " + answer);
validExpressions++;
} else{
invalidExcepressions++;
continue;
}
highestval=(highestval>=answer)?highestval:answer;
lowestval=(lowestval<=answer)?lowestval:answer;
total+=answer;
}
} else if ("K".equals(choice)){ // If the user enters K input will be taken from the keyboard
System.out.println("Please enter a post-fix expression:"); // User is prompted to enter a post fix expression
Scanner expression = new Scanner(System.in); // Creating a new Scanner called Expression to read user input
String exp = expression.nextLine(); // The user's input is stored in a string
String[] elements = exp.split(" "); // Expression is split into three elements, two numbers and an operator
String element1 = elements[0];
String element2 = elements[1];
String element3 = elements[2];
float num1 = Float.parseFloat(element1); // Element1 and element2 are converted to Floats and named num1 and num2
float num2 = Float.parseFloat(element2);
// Program processes the operator and applies it to Float num1 and Float num2 before outputting the
// expression and the correct answer
if ("+".equals(element3)) {
answer = num1 + num2;
System.out.println(element1 + " " + "+" + " " + element2 + " " + "=" + " " + answer);
validExpressions++;
} else if ("-".equals(element3)) {
answer = num1 - num2;
System.out.println(element1 + " " + "-" + " " + element2 + " " + "=" + " " + answer);
validExpressions++;
} else if ("*".equals(element3)) {
answer = num1 * num2;
System.out.println(element1 + " " + "*" + " " + element2 + " " + "=" + " " + answer);
validExpressions++;
} else if ("/".equals(element3)) {
answer = num1 / num2;
System.out.println(element1 + " " + "/" + " " + element2 + " " + "=" + " " + answer);
validExpressions++;
}else{
invalidExceotions++;
continue;
}
highestval=(highestval>=answer)?highestval:answer;
lowestval=(lowestval<=answer)?lowestval:answer;
total+=answer;
}else if (choice.isEmpty()) { // If the user does not enter K or F the program will exit
System.out.println("Evaluations Complete");
System.out.println("-------------------------");
System.out.println("Valid expressions: " + validExpressions);
System.out.println("Invalid expressions: " + invalidExpressions);
System.out.println("Total :"+total);
System.out.println("Average :"+total/validExceptions);
System.exit(0);
}
}

How do I output a draw from a vote (In Java)?

I have no idea on how to output a draw from a vote any help on with this would be appreciated.
At the moment it will allow a user to select the amount of candidates and then the user inputs details. Then the user will enter a vote, which is the candidate number, and type 999 to finish. The output will be the winner or winners(draw)the candidates with details and votes and the amount of spolit votes that is votes not in the range declared at the start.
int x;
char highestChar = '1';
char nextHighestChar = '1';
String alpha = "123456";
int largest=intVoteCount[1];
int nextLargest=intVoteCount[1];
for( x=1; x<=range; x++){
if(intVoteCount[x]>largest){
largest = intVoteCount[x];
highestChar = alpha.charAt(intLoopCount);
}
if(intVoteCount[x]>highestChar){
nextLargest = intVoteCount[x];
nextHighestChar = alpha.charAt(intLoopCount);
}
}
System.out.println("The winner is Candidate number "+ highestChar + " with " + largest + " votes.");
System.out.println("The winner is Candidate number "+ nextHighestChar + " with " + nextLargest + " votes.");
System.out.println("-----------------------------");
System.out.println("The Candidate votes are as follows.");
for (intLoopCount = 1; intLoopCount <= range; intLoopCount++) {
// Display all records.
// New Instance
System.out.println("");
System.out.println("Candidate " + intLoopCount + " "
+ strCandidateTitle[intLoopCount] + " "
+ strCandidateFirstname[intLoopCount] + " "
+ strCandidateSurname[intLoopCount] + " votes "
+ intVoteCount[intLoopCount]);
}
System.out.println("-----------------------------");
System.out.println("Vote Count Spolit: " + intVoteCountSpolit);
}
}

If largest == nextLargest you have a draw, so print out an appropriate message saying so; otherwise, you have an explicit winner.

Output after multiplication shows weird characters, JAVA

Hello fellow programmers.
Maybe it's a trivial question, yet I cant figure out solution, neither I can find any clue how to solve this. If its double post I am really sorry.
Here's the code: !! Don't forget to import your "java.util.Scanner" !!
double id[]=new double[4];
double price[]=new double[4];
String productName[]=new String[4];
id[0]=10001;
id[1]=10002;
id[2]=10003;
id[3]=10004;
price[0]=20;
price[1]=25;
price[2]=40;
price[3]=10;
productName[0]="T-Shirt";
productName[1]="More expensive T-Shirt";
productName[2]="Jacket";
productName[3]="Singlet";
int x=0;
int z=0;
int options;
double discount;
System.out.println("Type in number of your choice between 1 to 4");
Scanner menu = new Scanner(System.in);
options = menu.nextInt();
do {
System.out.println("Chosen product n.: "+ options);
}while (x > 0);
switch (options){
case 1:
System.out.println("Id of product: " + id[0] + " " + "Product price:" +price[0] + " " + "Name of product: " + productName[0]);
break;
case 2:
System.out.println("Id of product: " + id[1] + " " + "Product price: " +price[1] + " " + "Name of product: " + productName[1]);
break;
case 3:
System.out.println("Id of product: " + id[2] + " " + "Product price: " +price[2] + " " + "Name of product: " + productName[2]);
break;
case 4:
System.out.println("Id of product: " + id[3] + " " + "Product price: " +price[3] + " " + "Name of product: " + productName[3]);
break;
}
discount=idPrice(price);
System.out.println("Price after discount: " + price);
}
static double idPrice(double finalPrice[])
{
return (finalPrice[1]/0.8);
}
}
Here's the output after typing number 1:
Type in number of your choice between 1 to 4
1
Chosen product n.: 1
Id of product: 10001.0 Product price: 20.0 Name of product: T-Shirt
Price after discount: [D#3590efa8
As you can see the Price after discount is a mess. It should output number 20(25*0.8 (Hell yea 20% discount)).
That's the first question.
Next thing is. How can I spicify which finalPrice will be multiplied?
Thank you all. Hope it will be helpfull to someone else also.

You're printing an array, not it's elements.
In order to do so, you have to iterate through them:
for (double d : prices) {
System.out.println(d);
}
Edit:
After reading the comments, you should print the discount variable:
System.out.println("Price after discount: " + discount);

System.out.println("Price after discount: " + price);
Print Array of double------------------^
You need to iterate to print the price array like below
for (double d : price) {
System.out.println("Price is "+d);
}

Use java.util.Arrays.toString(price) to get a readable result.
What you are getting now is the default toString method of the Object object:
public String toString() {
return getClass().getName() + "#" + Integer.toHexString(hashCode());
}