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How do i rerun part of a code that uses an array?

I'm trying to make a code that takes a users input and prints their schedule, but I'm running into a problem with my do-while loop.
My program will not rerun. I'm getting an error that says:
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: Index 2 out of bounds for length 2 at com.company.Main.main(Main.java:25)
Here is my code:
import java.util.*;
public class Main {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
String rerun;
do {
System.out.println("What is your name?");
String name = input.nextLine();
System.out.println("How many courses do you have?");
int numCourse = input.nextInt();
input.nextLine();
String[][] timetable = new String[numCourse][2];
for (int j = 0; j < numCourse; j++) {
System.out.println("What is the name of your course #" + (j + 1) + "?");
String course = input.nextLine();
timetable[j][0] = course;
System.out.println("What is your teachers name for " + course + "?");
String teacher = input.nextLine();
timetable[j][1] = teacher;
}
System.out.println("Hello " + name + ", here is your timetable:");
for (int i = 0; i <= numCourse; i++) {
System.out.format("\n%-30s%-30s", "Course #" + (i+1) + ": " + timetable[i][0],"Teacher: " + timetable[i][1]);
}
System.out.println("Would anyone else like to print their schedule? (yes/no)");
rerun = input.next();
}while(rerun.equalsIgnoreCase("yes"));
System.out.println("Goodbye!");
}
}

Problem is in second for loop where you display your from array. put next() inplace of nextLine() because sometimes it skip the position.
Change
for (int i = 0; i <= numCourse; i++) {
System.out.format("\n%-30s%-30s", "Course #" + (i+1) + ": " + timetable[i][0],"Teacher: " + timetable[i][1]);
}
To
for (int i = 0; i < numCourse; i++) {
System.out.format("\n%-30s%-30s", "Course #" + (i+1) + ": " + timetable[i][0],"Teacher: " + timetable[i][1]);
}
Suppose your numCorse is 2. In your code, loop start from 0 and terminate after 2 so, Your loop working right while i is 0 and 1 but if i is going to 3 you get exception ArrayIndexOutOfBound.

How to end the while loop with either player1 or player2 entering "Q"?

I am stuck at a part where in a game, I use while loop and to end the loop and get the results of the game, I want either "player1" or "player2" to enter "Q", and so i tried doing it like this:
if (player1.equals("Q") || player2.equals("Q")){
go = false; //go is a boolean variable
}
This doesn't seem to work as I have to enter "Q" for both player1 and player2 for the game to end, but instead I just want either of them to enter "Q" and the game would stop.
Code:
import java.util.Scanner;
public class Team {
public static void main(String[] args) {
Scanner keyboard = new Scanner(System.in);
System.out.println("Soccer Game Between 2 Teams");
System.out.println("Win is 2 points" + "\n" + "Loss is worth 0 points" + "\n" + "Overtime is worth 1 point");
System.out.println("Type W, O, or L" + "\n" + "Type Q to end the game");
int pointsw = 0;
int pointsl = 0;
int pointso = 0;
int pointsw2 = 0;
int pointsl2 = 0;
int pointso2 = 0;
int totalpoints = 0;
int totalpoints2 = 0;
int counter = 0;
int counter2 = 0;
boolean go = true;
System.out.println("\n" + "Enter team one:");
String phrase = keyboard.next();
System.out.println("\n" + "Enter team two:");
String phrase2 = keyboard.next();
System.out.println();
while (go) {
System.out.println("Enter " + phrase + " Result:");
String team1 = keyboard.next();
System.out.println("Enter " + phrase2 + " Result");
String team2 = keyboard.next();
if (team1.equals("W") || team1.equals("w")) {
pointsw += 2;
} else if (team1.equals("O") || team1.equals("o")) {
pointso += 1;
} else if (team1.equals("L") || team1.equals("l")) {
pointsl += 0;
}
counter++;
if (team2.equals("W") || team2.equals("w")) {
pointsw2 += 2;
} else if (team2.equals("O") || team2.equals("o")) {
pointso2 += 1;
} else if (team2.equals("L") || team2.equals("l")) {
pointsl2 += 0;
}
counter2++;
totalpoints = pointsw + pointso + pointsl;
totalpoints2 = pointsw2 + pointso2 + pointsl2;
if (team1.equals("Q") || team2.equals("Q")) {
go = false;
if (totalpoints > totalpoints2) {
System.out.println(phrase + " wins with " + totalpoints + " points");
System.out.println("It took " + phrase + " " + counter + " rounds to win");
} else if (totalpoints < totalpoints2) {
System.out.println(phrase2 + " wins with " + totalpoints2 + " points");
System.out.println("It took " + phrase2 + " " + counter2 + " rounds to win");
} else if (totalpoints == totalpoints2) {
int totalrounds = counter + counter2;
System.out.println("It is tie game between " + phrase + " and " + phrase2);
System.out.println("The game lasted till " + totalrounds + " rounds");
}
}
}
}
}

You should reorganize your code:
while (true) {
System.out.println("Enter " + phrase + " Result:");
String team1 = keyboard.next().toLowerCase();
if ("q".equals(team1)) {
break;
}
System.out.println("Enter " + phrase2 + " Result");
String team2 = keyboard.next().toLowerCase();
if ("q".equals(team2)) {
break;
}
if (team1.equals("w")) {
pointsw += 2;
} else if (team1.equals("o")) {
pointso += 1;
} else if (team1.equals("l")) {
pointsl += 0;
}
counter++;
if (team2.equals("w")) {
pointsw2 += 2;
} else if (team2.equals("o")) {
pointso2 += 1;
} else if (team2.equals("l")) {
pointsl2 += 0;
}
counter2++;
totalpoints = pointsw + pointso + pointsl;
totalpoints2 = pointsw2 + pointso2 + pointsl2;
} // loop completed
if (totalpoints > totalpoints2) {
System.out.println(phrase + " wins with " + totalpoints + " points");
System.out.println("It took " + phrase + " " + counter + " rounds to win");
} else if (totalpoints < totalpoints2) {
System.out.println(phrase2 + " wins with " + totalpoints2 + " points");
System.out.println("It took " + phrase2 + " " + counter2 + " rounds to win");
} else if (totalpoints == totalpoints2) {
int totalrounds = counter + counter2;
System.out.println("It is tie game between " + phrase + " and " + phrase2);
System.out.println("The game lasted till " + totalrounds + " rounds");
}

I'm not completely sure, but I think the issue is that after player 1 / player 2 says 'Q'
the scanner is still waiting for the next line to read.
String phrase = keyboard.next();
System.out.println("\n"+"Enter team two:");
String phrase2 = keyboard.next();//if player 1 types q this next() method must be resolved before it will continue to the logic
so add an if statement before play 2 goes asking if player 1 typed 'Q' , if so calculate scores and end game, if player 1 did not type 'Q' use else statement to continue on to player 2's turn

output comes out to an integer when I want a string

import java.util.Scanner;
public class QuestionTwo{
public static void main(String[] args) {
Integer number;
Character first, middle, last;
Scanner keyboard = new Scanner(System.in);
System.out.print("First name: ");
first = keyboard.next().charAt(0);
System.out.print("Middle name: ");
middle = keyboard.next().charAt(0);
System.out.print("Last name: ");
last = keyboard.next().charAt(0);
System.out.print("Which type of sort order would you like (1 for ascending and 2 for descending)? ");
number = keyboard.nextInt();
if (number == 1) {
System.out.println("Sort order: 1");
if ((first) < (middle) && (first) < (last)) {
if ((middle) < (last)) {
System.out.println(first + middle + last);
}
if ((last) < (middle)) {
System.out.println(first + last + middle);
}
}
if ((middle) < (first) && (middle) < (last)) {
if ((first) < (last)) {
System.out.println(middle + first + last);
}
if ((last) < (first)) {
System.out.println(middle + last + first);
}
}
if ((last) < (middle) && (last) < (first)) {
if ((middle) < (first)) {
System.out.println(last + middle + first);
}
if ((first) < (middle)) {
System.out.println(last + first + middle);
}
}
}
if (number == 2) {
System.out.println("Sort order: 2");
if ((first) > (middle) && (first) > (last)) {
if ((middle) > (last)) {
System.out.println(first + middle + last);
}
if ((last) > (middle)) {
System.out.println(first + last + middle);
}
}
if ((middle) > (first) && (middle) > (last)) {
if ((first) > (last)) {
System.out.println(middle + first + last);
}
if ((last) > (first)) {
System.out.println(middle + last + first);
}
}
if ((last) > (middle) && (last) > (first)) {
if ((middle) > (first)) {
System.out.println(last + middle + first);
}
if ((first) > (middle)) {
System.out.println(last + first + middle);
}
}
}
}
}
The output that I get from this is a large integer value, whereas what the program should do is ask for a first name, then middle name, then last name. It should then ask for which sort order, 1 being ascending and 2 being descending. What this means is that once it gets the name it looks through the names and counts the number of letters per name. It will then give the answer as the name sorted in the order that the user selected.
For example:
if I tell it my name is David H. Anderson, and click 1 for ascending order, my result should be "H. David Anderson", as H. is 2 symbols, David is 5 and Anderson is 8.
What it currently does is all of the above except for giving me the last line int he format I want (I end up just getting a number).

I would change a few things to get you started.
Firstly, your input should probably be a String
Secondly, remove .charAt(0)
Then compare the String lengths before printing them.

Try this:
import java.util.ArrayList;
import java.util.Collections;
import java.util.Scanner;
public class Main2 {
private static ArrayList<String> splitAndSortFullName(String fullName, int sortOrder) {
String[] names = fullName.split(" "); //Split names by space character.
//Create a list with only non-empty names:
ArrayList<String> namesList = new ArrayList();
for (int i=0; i<names.length; ++i)
if (!names[i].isEmpty())
namesList.add(names[i]);
switch (sortOrder) {
case 1: Collections.sort(namesList); break;
case 2: Collections.sort(namesList, (a, b) -> { return b.compareTo(a); }); break;
}
return namesList;
}
public static void main(String[] args) {
Scanner keyboard = new Scanner(System.in);
System.out.print("Enter full name: ");
String fullName = keyboard.nextLine(); //Read the full name. For example "John D. Doe".
System.out.print("Which type of sort order would you like (1 for ascending and 2 for descending)? ");
int number = keyboard.nextInt();
System.out.println(splitAndSortFullName(fullName, number));
//For use with many full names, just re-call the method splitAndSortFullName(...). For examples:
System.out.println("Full examples:");
System.out.println(splitAndSortFullName("John D. Doe", 1));
System.out.println(splitAndSortFullName("Alice K. Example", 2));
System.out.println(splitAndSortFullName("Martin T. Anderson", 1));
}
}
In this code, the user enters his complete name fully.

import java.util.Scanner;
public class QuestionTwo
{
public static void main(String[] args)
{
Integer number;
String first, middle, last;
Scanner keyboard = new Scanner (System.in);
System.out.print("First name: ");
first = keyboard.next();
System.out.print("Middle name: ");
middle = keyboard.next();
System.out.print("Last name: ");
last = keyboard.next();
System.out.print("Which type of sort order would you like (1 for ascending and 2 for descending)? ");
number = keyboard.nextInt();
int firstLength = first.length();
int middleLength = middle.length();
int lastLength = last.length();
if(number == 1)
{
System.out.println("Sort order: 1");
if(firstLength < middleLength && firstLength < lastLength)
{
if(middleLength < lastLength)
{
System.out.println (first + " " + middle + " " + last);
}
if(lastLength < middleLength)
{
System.out.println (first + " " + last + " " + middle);
}
}
if(middleLength < firstLength && middleLength < lastLength)
{
if(firstLength < lastLength)
{
System.out.println (middle + " " + first + " " + last);
}
if(lastLength < firstLength)
{
System.out.println (middle + " " + last + " " + first);
}
}
if(lastLength < middleLength && lastLength < firstLength)
{
if(middleLength < firstLength)
{
System.out.println(last + " " + middle + " " + first);
}
if(firstLength < middleLength)
{
System.out.println(last + " " + first + " " + middle);
}
}
}
if(number == 2)
{
System.out.println("Sort order: 2");
if(firstLength > middleLength && firstLength > lastLength)
{
if(middleLength > lastLength)
{
System.out.println (first + " " + middle + " " + last);
}
if(lastLength > middleLength)
{
System.out.println (first + " " + last + " " + middle);
}
}
if(middleLength > firstLength && middleLength > lastLength)
{
if(firstLength > lastLength)
{
System.out.println (middle + " " + first + " " + last);
}
if(lastLength > firstLength)
{
System.out.println (middle + " " + last + " " + first);
}
}
if(lastLength > middleLength && lastLength > firstLength)
{
if(middleLength > firstLength)
{
System.out.println(last + " " + middle + " " + first);
}
if(firstLength > middleLength)
{
System.out.println(last + " " + first + " " + middle);
}
}
}
}
}
Listening to the comments and with help from thanopi57, I was able to get the proper answer. The first thing I did was to remove the ".AtChar(0)" and define the variables as Strings, not Characters. I then defined the variables as variable length, with variable xxxx becoming int xxxxLength=xxxx.Length();, doing this for all three variables (which converted them from String to Int). I then replaced the subsequent concatenation operands with my newly defined variables, I also added " " for spaces inbetween operands in the println lines.

line of Java is printing duplicates

case 2:
System.out.println("Please enter Book ID: ");
String userinput2 = sc.next();
for (int i = 0; i < myBooks.size(); i++) {
if (myBooks.get(i).getBookID().contains(userinput2)) {
System.out.println("BookID: " + myBooks.get(i).getBookID() + "\nTitle: "
+ myBooks.get(i).getTitle() + "\nAuthor: " + myBooks.get(i).getAuthor());
System.out.println("Please enter new details of book");
System.out.println("Title: ");
String userinput7 = sc.next();
myBooks.get(i).setTitle(userinput7);
System.out.println("Author: ");
String u1 = sc.next();
myBooks.get(i).setAuthor(u1);
myBooks.get(i).setOnLoan(false);
myBooks.get(i).setNumLoans(0);
System.out.println("---------------------------------------------------");
System.out.println("The book has been successfully updated");
System.out.println("Book ID: " + myBooks.get(i).getBookID() + " " + "\nTitle: "
+ myBooks.get(i).getTitle() + " " + "\nAuthor: " + myBooks.get(i).getAuthor());
System.out.println("---------------------------------------------------");
}
else { System.out.println("Please enter a correct bookID");
}
}
I'm having a problem with my validation check. If the user enters a bookID that doesn't exist, instead of printing out "please enter a correct bookID" once, it prints it out 4 times, which amounts to the number of objects i have in the array list. Is there a way to sort this?

Your else statement is in the middle of the for statement
for (int i = 0; i < myBooks.size(); i++) {
if (myBooks.get(i).getBookID().contains(userinput2)) {
[[do stuff]]
}
else { System.out.println("Please enter a correct bookID");
}
}
It looks like it should be in the middle of the if statement
if (myBooks.get(i).getBookID().contains(userinput2)) {
for (int i=...) {
[[do stuff]]
}
}
else { System.out.println("Please enter a correct bookID");
}

multidimensional arrays and methods

I have a homework assignment and the program generates a random number of students taking a random number of tests. The user must enter the students names and test scores. Once that is done the program will print on the screen : STUDENT REPORT Scores for Fred:
Test #1: 78
Test #2: 80
Average for Fred: 79.0
Scores for Sue:
Test #1: 91
Test #2: 94
Average for Sue: 92.5
... and so on depending on what number of students and tests you get.
I get everything right up until the average part how can I fix it?
Here's my code:
public static void populateNames(String[] names)
{
for(int i = 0; i<names.length; i++)
{
out.print("Enter student " + (i+1) + " name: ");
names[i] = keyboard.next();
}
}
// Code your 3 methods below...
//Ask the user for the student name as well as the test scores
public static void populateTestScores(String[] names, int[][] scores)
{
out.println();
for(int i=0; i<names.length; i++)
{
out.println();
out.println("Entering scores for: " + names[i]);
for(int s=0; s<scores[0].length; s++)
{
out.print("Enter score for test #" + (s+1) + ": ");
scores[i][s] = keyboard.nextInt();
}
}
out.println();
}
//Print each studdent test scores and ther average
public static void printStudentReport(String[] names, int[][] scores)
{
out.println("STUDENT REPORT");
for(int i=0; i<names.length; i++)
{
out.print("Scores for " + names[i] + ": ");
out.println();
for(int s=0; s<scores[0].length; s++)
{
out.println("Test #" + (s + 1) + ": " + scores[i][s]);
}
out.println();
int s=0;
if(s<scores[0].length)
{
s++;
double sum = 0;
sum += scores[i][s];
double average = sum / scores[0].length;
out.println("Average for " + names[i] + ": " + average);
out.println();
}
}
out.println();
}

The problem is in the way you're computing sum in printStudentReport: it only contains the second element in the list of scores because you're creating and adding to sum after the for loop (instead of creating before the loop and adding in it).
I'd rearrange that method to (reformatted for compactness):
// Print each studdent test scores and ther average
public static void printStudentReport(String[] names, int[][] scores) {
out.println("STUDENT REPORT");
for (int i = 0; i < names.length; i++) {
out.print("Scores for " + names[i] + ": ");
out.println();
double sum = 0;
for (int s = 0; s < scores[0].length; s++) {
out.println("Test #" + (s + 1) + ": " + scores[i][s]);
sum += scores[i][s];
}
out.println();
if (0 < scores[0].length) {
double average = sum / scores[0].length;
out.println("Average for " + names[i] + ": " + average);
out.println();
}
}
out.println();
}