Thread: Need to add an error, and return the correct values in a dialog box

Hi!
Sorry in advance if this is really long or a bad question, I am new to Java and object-oriented programming and easily confused.

My class very briefly in the first assignment like.... 4 weeks ago touched on the JOptionPane, but I can't find anything I need from the book or from the first assignment except the basics, so I was hoping someone could help!

This is the assignment:

"Write an application containing three parallel arrays that hold 10 elements each. The first array hold four-digit student ID numbers, the second array holds first names, and the third array holds the students’ grade point averages. Use dialog boxes to accept a student ID number and display the student’s first name and grade point average. If a match is not found, display an error message that includes the invalid ID number and allow the user to search for a new ID number."

I am stuck on the error message, mainly: I have not worked in JOptionPane more than once, and what you'll see in my code is basically all I've ever done.
Furthermore, what I have doesn't return the correct values: the dialog box returns the correct text, but the wrong format and a bunch of weird symbols instead of the corresponding FirstName and GPA ("First name: [Ljava.lang.String;@57e1b0cGPA:[D@4232c52b").

This is my code so far:

import javax.swing.JOptionPane;

public class Assignment1 {
public static void main(String[]args) {

int [] StudentID = {1234, 5678, 9101, 1213, 1415, 1617, 1819, 2021, 2223, 2425};
String[] FirstName = {"Bob", "Joe", "Jane", "John", "Roman", "Billy", "Casy", "Kylie", "Raimy", "Abby"};
double [] GPA = {3.4, 3.6, 2.1, 1.2, 4.0, 3.7, 1.0, 3.7, 3.9, 3.4};

JOptionPane.showInputDialog(null, "Enter student ID");



JOptionPane.showMessageDialog(null, "First name: " + FirstName + "GPA: " + GPA);
}

}




I've attempted if....else, and a do....while, but I'm really confused by how to check if the user-input number = the StudentID

To achieve your goal, you need to search for the entered student ID in the `StudentID` array and then display the corresponding first name and GPA if a match is found. Otherwise, you should show an error message. Here's the modified version of your code to accomplish this:

```java
import javax.swing.JOptionPane;

public class Assignment1 {
public static void main(String[] args) {
int[] StudentID = {1234, 5678, 9101, 1213, 1415, 1617, 1819, 2021, 2223, 2425};
String[] FirstName = {"Bob", "Joe", "Jane", "John", "Roman", "Billy", "Casy", "Kylie", "Raimy", "Abby"};
double[] GPA = {3.4, 3.6, 2.1, 1.2, 4.0, 3.7, 1.0, 3.7, 3.9, 3.4};

// Prompt user to enter student ID
String input = JOptionPane.showInputDialog(null, "Enter student ID");

// Convert the input to an integer
int searchID = Integer.parseInt(input);

// Initialize variables to hold found data
String foundFirstName = null;
double foundGPA = 0.0;
boolean found = false;

// Search for the entered student ID in the array
for (int i = 0; i < StudentID.length; i++) {
if (searchID == StudentID[i]) {
foundFirstName = FirstName[i];
foundGPA = GPA[i];
found = true;
break;
}
}

// If a match is found, display the student's details
if (found) {
JOptionPane.showMessageDialog(null, "First name: " + foundFirstName + "\nGPA: " + foundGPA);
} else {
// If no match is found, display an error message
JOptionPane.showMessageDialog(null, "Error: Student ID " + searchID + " not found.");
}
}
}
```

This code prompts the user to enter a student ID, searches for that ID in the `StudentID` array, and then displays the corresponding first name and GPA if found. If the ID is not found, it shows an error message.

If no match is found, display an error message. Remember, seeking assistance with Java assignments can provide valuable insights and guidance to overcome hurdles. Additionally, exploring various online resources and seeking help from experienced programmers can further enhance your understanding and proficiency in Java programming. Understanding these concepts deeply can assist you in tackling similar challenges in the future. There are various online platforms, such as programminghomeworkhelp.com, where you can find help with Java assignment.