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Reading a .txt file into a parallel array - java

I need some assistance with my program. Using an example program that was similar I was able to get the basic layout of everything I needed to do. Right now my main questions is if my code is correct for the first part. I want it to read the data from my data file into a parallel array. I included my entire program for reference of the layout, but for now I'm just trying to read the data file into an array. Any help is greatly appreciated. Let me know if more information is needed or if my formatting is wrong.
Data File (patient.txt):
11111,Smith,Norris,Thyroid,1000.00
11112,Obama,Norris,Lasek,500.00
11113,Hoover,Norris,Dental,100.00
11114,Cena,Norris,Lasek,500.00
11115,Leto,Norris,Thyroid,1000.00
22221,Clark,Bond,Thyroid,1000.00
22222,Chang,Bond,Lasek,500.00
22223,Dent,Bond,Dental,100.00
22224,Nixon,Bond,Lasek,500.00
22225,Washington,Bond,Dental,100.00
33331,Jones,Lee,Dental,100.00
33332,Ross,Lee,Lasek,500.00
33333,Gates,Lee,Thyroid,1000.00
33334,Johnson,Lee,Thyroid,1000.00
33335,Carter,Lee,Dental,100.00
Program (class is Patient_Reports)
`
import javax.swing.JOptionPane;
import java.io.*;
import java.util.*;
public class Patient_Reports {
public static void main(String[] args)
{
int selection;
String pnumber;
Patient_Reports patient = new Patient_Reports();
patient.start_system();
pnumber = patient.menu();
selection = Integer.parseInt(pnumber);
while(selection !=3)
{
if(selection==1)
patient.All_Information_Report();
else
if(selection==2)
patient.Surgeries_Doctor_Report();
else
if(selection==3)
patient.Surgeries_Type_Report();
else
if(selection==4)
patient.Doctor_Fees_Report();
else
if(selection==5)
patient.Average_Fees_Report();
pnumber = patient.menu();
selection = Integer.parseInt(pnumber);
}//while loop
patient.Exit();
System.exit(0);
}//main method
//Read Data File
int count=-1,i;
int [] id = new int [10];
String [] patient = new String [10];
String [] doctor = new String [10];
String [] surgery = new String [10];
double [] cost = new double [10];
void start_system()
{
String newLine;
try
{
//define a file valiable for Buffered read
BufferedReader Patient_Reports = new BufferedReader(new FileReader("patient.txt"));
//read lines in file until there are no more lines in the file to read
while ((newLine = Patient_Reports.readLine()) != null)
{
//there is a "," between each data item in each line
StringTokenizer delimiter = new StringTokenizer(newLine,",");
count=count+1;
id[count] = Integer.parseInt(delimiter.nextToken());
patient[count] =delimiter.nextToken();
doctor[count] =delimiter.nextToken();
surgery[count] =delimiter.nextToken();
cost[count] = Double.parseDouble(delimiter.nextToken());
}//while loop
Patient_Reports.close();
}//end try
catch (IOException error)
{
//there was an error on the file writing
System.out.println("Error on file read " + error);
}//error on read
}//end start_system
//Method for Menu of Reports
String menu()
{
String pnum;
String Output = "Reports" + "\n" +"1. All_Information_Report" + "\n" +
"2. Surgeries_Doctor_Report" + "\n" +
"3. Surgeries_Type_Report" + "\n" +
"4. Doctor_Fees_Report" + "\n" +
"5. Average_Fees_Report" + "\n" +
"6. Exit" + "\n" +
" " + "\n" +
"Select a Report >";
pnum = JOptionPane.showInputDialog(null,
Output, "",JOptionPane.QUESTION_MESSAGE);
return pnum;
}//end menu
/* Placeholder for the Reports
//All_Information_Report Report containing all of the information
void All_Information_Report()
{
System.out.println("All_Information_Report");
for (i=0; i<=count; ++i)
{
System.out.println(id[i] + " " + patient[i] + " " + doctor[i] + " " + surgery[i] + " " + cost[i] + " ");
}//for loop
}//end report
//Surgeries_Doctor_Report Report on all surgeries of a specific doctor (prompt for the doctor)
void Surgeries_Doctor_Report()
{
System.out.println("Surgeries_Doctor_Report");
for (i=0; i<=count; ++i)
{
System.out.println(id[i] + " " + patient[i] + " " + doctor[i] + " " + surgery[i] + " " + cost[i] + " ");
}//for loop
}//end report
//Surgeries_Type_Report Report on all surgeries of a specific type(Prompt for the surgery type)
void Surgeries_Type_Report()
{
System.out.println("Surgeries_Type_Report");
for (i=0; i<=count; ++i)
{
System.out.println(id[i] + " " + patient[i] + " " + doctor[i] + " " + surgery[i] + " " + cost[i] + " ");
}//for loop
}//end report
//Doctor_Fees_Report Report on the total amount of fees paid to each doctor
void Doctor_Fees_Report()
{
System.out.println("Doctor_Fees_Report");
for (i=0; i<=count; ++i)
{
System.out.println(id[i] + " " + patient[i] + " " + doctor[i] + " " + surgery[i] + " " + cost[i] + " ");
}//for loop
}//end report
//Average_Fees_Report Report on the Average Fee
void Average_Fees_Report()
{
System.out.println("Average_Fees_Report");
for (i=0; i<=count; ++i)
{
System.out.println(id[i] + " " + patient[i] + " " + doctor[i] + " " + surgery[i] + " " + cost[i] + " ");
}//for loop
}//end report
*/
//Store Data File in Array
void Exit()
{
try
{
BufferedWriter Patient_Reports = new BufferedWriter(new FileWriter("patient.txt"));
for (i=0; i<=count; ++i)
{
//put "," between each data item in the file
Patient_Reports.write(id[i] + "," + patient[i] + "," + doctor[i]+ "," + surgery[i] + ","+ cost[i]+ ",");
//write a new line in the file
Patient_Reports.newLine();
}//for loop
Patient_Reports.close();
}//end try
catch (IOException error)
{
//there was an error on the write to file
System.out.println("Error on file write " + error);
}//end error
}//end class
}//end exit_system`

To begin, your code is VERY confusing and violates several OOP programming conventions.
The first (and most egregious) problem is that your static class Patient_Reports contains the main method but does not utilize this static entry point to declare an object or advance. So, it would behoove you to reformat your code like this:
public class Patient_Reports {
Patient_Reports fields...
public Patient_Report() {
//start work here in Constructor
}
Patient_Reports methods...
public static void main(String[] args) {
new Patient_Reports();
}
}
To address your main question, you would want to have some sort of generalized method you could call within your class like this:
public static void writePatientReports(int[] id, String[] patient,
String[] doctor, String[] surgery, double[] cost) {
BufferedWriter Student_file = new BufferedWriter(new FileWriter("patient.txt"));
for (i=0; i<=count; ++i)
{
//put "," between each data item in the file
Student_file.write(id[i] + "," + patient[i] + "," + doctor[i]+ "," + surgery[i] + ","+ cost[i]+ ",");
//write a new line in the file
Student_file.write("\n");
}//for loop
Student_file.close();
}
The reason you were getting errors is because you had no methods attached to Patient_Reports like write() or newLine(). And even if you had, you would have needlessly declared Student_file as a BufferedWriter object.
Further, you would do greatly in furthering your knowledge of Java and general OOP by reading Java Code Conventions

Related

I have to display all of records in my blocks (text files), and do a split to "cover" the Fields Separators, but only the first record of my blocks are diplayed. What am I doing wrong?
enter code here
public static void listAllStudents() throws IOException {
File path = new File(Descriptor.getBlockPath());
for (int i = 0; i < path.listFiles().length; i++) {
try {
FileInputStream file = new FileInputStream(Descriptor.getBlockPath() + "BLK" + i + ".txt");
InputStreamReader entrada = new InputStreamReader(file);
BufferedReader buf= new BufferedReader(entrada);
String piece = " ";
System.out.println("\nBLOCO " + i + " ------------------------------------------------------ +");
do {
if (buf.ready()) {
piece = buf.readLine();
System.out.println("\n¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨¨");
String string = " ", field[] = piece.split(Descriptor.getFieldSeparator());
string = " ";
System.out.println("CPF: " + field[0]);
System.out.println("Name: " + field[1]);
System.out.println("Course: " + field[2]);
System.out.println("Age: " + field[3]);
System.out.println("Phone: " + field[4]);
System.out.println("Active: " + field[5]);
string = " ";
}
} while (buf.ready());
buf.close();
} catch (IOException e) {
System.out.println();
}
}
}

See the documentation for the BufferedReader.readLine() method:
or null if the end of the stream has been reached
Then change your code to read the file line by line:
while ((piece = buf.readLine()) != null) {
String field[] = piece.split(Descriptor.getFieldSeparator());
if (field.length >= 6) {
System.out.println("CPF: " + field[0]);
System.out.println("Name: " + field[1]);
System.out.println("Course: " + field[2]);
System.out.println("Age: " + field[3]);
System.out.println("Phone: " + field[4]);
System.out.println("Active: " + field[5]);
}
}

I'm pretty new to Java and I'm having some trouble figuring out where I'm going wrong with my program. I have it so it's doing a mad libs sort of thing where it reads a document with questions(or categories), then prompts for an answer on loop till it has all the answers. It commits these answers to a text file called "answers" then reads the file and prints a message, along with another file containing the full madlib.
I don't actually get an error upon compiling but after I've input all the answers I get
Exception in thread "main" java.util.NoSuchElementException: no line found
-at java.util.Scanner.nextLine(Scanner.java:1540)
-at reader.main(reader.java:68)
Here's the complete code for reference
import java.util.Scanner; // importing scanner object for usage
import java.io.*;
import java.io.PrintWriter;
public class reader{
public static void main(String[] args) throws IOException
{
Scanner keyboard = new Scanner(System.in);
System.out.println("enter the name of a file");
String filename = keyboard.nextLine();
File file = new File(filename);
Scanner inputFile = new Scanner(file);
int limit = inputFile.nextInt();
int n;
inputFile.nextLine();
PrintWriter answers = new PrintWriter("answers.txt");
for(n = 0; n < limit; n++)
{
String line = inputFile.nextLine();
System.out.println(line);
String answer = keyboard.nextLine();
answers.println(answer);
}
inputFile.close();
answers.close();
File useanswers = new File("answers.txt");
Scanner inputFile2 = new Scanner(useanswers);
String outputline = inputFile2.nextLine();
String outputline2 = inputFile2.nextLine();
String outputline3 = inputFile2.nextLine();
String outputline4 = inputFile2.nextLine();
String outputline5 = inputFile2.nextLine();
String outputline6 = inputFile2.nextLine();
String outputline7 = inputFile2.nextLine();
String outputline8 = inputFile2.nextLine();
String outputline9 = inputFile2.nextLine();
String outputline10 = inputFile2.nextLine();
String outputline11 = inputFile2.nextLine();
String outputline12 = inputFile2.nextLine();
String outputline13 = inputFile2.nextLine();
String outputline14 = inputFile2.nextLine();
String outputline15 = inputFile2.nextLine();
String outputline16 = inputFile2.nextLine();
String outputline17 = inputFile2.nextLine();
String outputline18 = inputFile2.nextLine();
String outputline19 = inputFile2.nextLine();
PrintWriter result = new PrintWriter("Madlibs_result.txt");
System.out.println("Batman is " + outputline + ". Teenager " + outputline2 +
"was traumatized by " + outputline3 + "his parent's murder and vowed to " + outputline4 +
" their deaths by bringing the " + outputline5 + " to justice. " + outputline6 + " used his " +
outputline7 + "fortune to study criminology, to train his body to " + outputline8 + " perfection, " +
"and to acquire hight tech vehicles and " + outputline9 + " to fight crime in his homw town of " + outputline10 + ". One night " +
outputline11 + "was " + outputline + " by a bat outside his window and decided to dress himself as a \"bat man\" to strike " +
outputline12 + " in the \"" + outputline13 + " and " + outputline14 + "\" hearts of " + outputline15 + ". From that moment forward, " +
outputline16 + " became \"Batman\" in his altered " + outputline17);
result.println("Batman is " + outputline + ". Teenager " + outputline2 +
"was traumatized by " + outputline3 + "his parent's murder and vowed to " + outputline4 +
" their deaths by bringing the " + outputline5 + " to justice. " + outputline6 + " used his " +
outputline7 + "fortune to study criminology, to train his body to " + outputline8 + " perfection, " +
"and to acquire hight tech vehicles and " + outputline9 + " to fight crime in his homw town of " + outputline10 + ". One night " +
outputline11 + "was " + outputline + " by a bat outside his window and decided to dress himself as a \"bat man\" to strike " +
outputline12 + " in the \"" + outputline13 + " and " + outputline14 + "\" hearts of " + outputline15 + ". From that moment forward, " +
outputline16 + " became \"Batman\" in his altered " + outputline17);
result.close();
}
}

Resolved, I had too many String outputline... lines, and I assume when it tried to go to the nonexistent 19th and 20th lines of the text file created, it gave me an error.

Closed. This question needs debugging details. It is not currently accepting answers.
Edit the question to include desired behavior, a specific problem or error, and the shortest code necessary to reproduce the problem. This will help others answer the question.
Closed 7 years ago.
Improve this question
I have created a counting game and I have tried to create a highscore method.
The problem is the program returns "null" when the "Highscore" menu is chosen. What could be causing this?
import javax.swing.*;
import java.text.DecimalFormat;
import java.util.*;
import java.io.*;
public class Räknesätt {
public static void main(String[]args) throws IOException {
DecimalFormat df = new DecimalFormat("0.00");
int input = Integer.parseInt(JOptionPane.showInputDialog(null, "-------------------------" + "\n\n" +
"1. Spela" + "\n" +
"2. Highscores" + "\n" +
"3. Avsluta" + "\n\n" +
"-------------------------"));
if(input == 2) {
String highscores = "";
int rader = countline("Highscores");
BufferedReader inström1 = new BufferedReader
(new FileReader("Highscores"));
for(int i = 0; i <= rader; i++) {
highscores = inström1.readLine() + "\n";
}
JOptionPane.showMessageDialog(null, highscores);
}
else if(input == 3) {
System.exit(0);
}
else if(input == 1) {
String namn = JOptionPane.showInputDialog(null, "Skriv in ditt namn");
int counter = 0;
int rätt = 0;
int fel = 0;
while(counter < 10) {
int slump1 = 1 + (int)(Math.random()*100);
int slump2 = 1 + (int)(Math.random()*100);
List<String> räknesätt = new LinkedList<String>(Arrays.asList("+",
"-",
"*",
"/"));
int räknesättRand = (int)(Math.random()*4);
String räknesättStr = räknesätt.get(räknesättRand);
counter++;
switch(räknesättStr) {
case "+":
String svarStr1 = JOptionPane.showInputDialog(null,namn + " räkna ut: " + "\n" + slump1 + " + " + slump2 + " = ");
int svar1 = Integer.parseInt(svarStr1);
if(svar1 == slump1 + slump2) {
JOptionPane.showMessageDialog(null, namn + " du räknade rätt!");
rätt++;
}
else {
JOptionPane.showMessageDialog(null, namn + " du räknade fel!");
fel++;
}
break;
case "-":
String svarStr2 = JOptionPane.showInputDialog(null,namn + " räkna ut: " + "\n" + slump1 + " - " + slump2 + " = ");
int svar2 = Integer.parseInt(svarStr2);
if(svar2 == slump1 - slump2) {
JOptionPane.showMessageDialog(null, namn + " du räknade rätt!");
rätt++;
}
else {
JOptionPane.showMessageDialog(null, namn + " du räknade fel!");
fel++;
}
break;
case "*":
String svarStr3 = JOptionPane.showInputDialog(null,namn + " räkna ut: " + "\n" + slump1 + " * " + slump2 + " = ");
int svar3 = Integer.parseInt(svarStr3);
if(svar3 == slump1 * slump2) {
JOptionPane.showMessageDialog(null, namn + " du räknade rätt!");
rätt++;
}
else {
JOptionPane.showMessageDialog(null, namn + " du räknade fel!");
fel++;
}
break;
case "/":
String svarStr = JOptionPane.showInputDialog(null,namn + " räkna ut: " + "\n" + slump1 + " / " + slump2 + " = ");
int svar = Integer.parseInt(svarStr);
if(svar == (double)slump1 / slump2) {
JOptionPane.showMessageDialog(null, namn + " du räknade rätt!");
rätt++;
}
else {
JOptionPane.showMessageDialog(null, namn + " du räknade fel!");
fel++;
}
break;
}
}
JOptionPane.showMessageDialog(null, "Resultat för: " + namn + "\n\n" +
"=========================" + "\n" +
"Antal räknade tal: " + counter + "\n" +
"Antal rätt: " + rätt + "\n" +
"Antal fel: " + fel + "\n" +
"Rättprocent: " + (double)100*rätt/(rätt+fel) + "%");
PrintWriter utström1 = new PrintWriter
(new BufferedWriter
(new FileWriter("Highscores")));
utström1.println(namn + ", " + (double)100*rätt/(rätt+fel) + "% rätt");
utström1.close();
}
}
public static int countline (String filnamn)throws IOException {
BufferedReader inström1 = new BufferedReader
(new FileReader(filnamn));
int lines = 0;
while(inström1.readLine() != null) {
++lines;
}
inström1.close();
return lines;
}
}

Code is trying to open a handle to a non-existent file by the name 'Highscores'.
Problem is being caused by the following line of code :
BufferedReader inström1 = new BufferedReader
(new FileReader("Highscores"));
The solution would be to create this file upfront, at the beginning of the program and write default contents into it.
Here is how you can go about doing it.
private static void createHighScoreFile() throws IOException {
PrintWriter printWriter = new PrintWriter
(new BufferedWriter
(new FileWriter("Highscores")));
printWriter.write("0\n");
printWriter.close();
}
public static void main(String[] args) throws IOException {
createHighScoreFile();
DecimalFormat df = new DecimalFormat("0.00");
There is also one more issue related to reading the contents of the file.
The condition in the for loop attempts to read an extra line from the file, which turns out to be null always. It needs to be fixed this way.
for (int i = 0; i <= rader; i++) {
to
for (int i = 0; i < rader; i++) {

Okay so now I got my code to compile and run, but the output is incorrect now. I need to be able to select an option and then for 2, and 3 have 3 additional options after selecting that option. How should I adapt my coding to do this?
Task:
List of all information
List of all surgeries for a specific doctor (prompt for the doctor)
List of all surgeries of a specific type (prompt for the surgery type)
Total amount of surgery fees paid to each Doctor
Average Fees
Data File (patient.txt):
11111,Smith,Norris,Thyroid,1000.00
11112,Obama,Norris,Lasek,500.00
11113,Hoover,Norris,Dental,100.00
11114,Cena,Norris,Lasek,500.00
11115,Leto,Norris,Thyroid,1000.00
22221,Clark,Bond,Thyroid,1000.00
22222,Chang,Bond,Lasek,500.00
22223,Dent,Bond,Dental,100.00
22224,Nixon,Bond,Lasek,500.00
22225,Washington,Bond,Dental,100.00
33331,Jones,Lee,Dental,100.00
33332,Ross,Lee,Lasek,500.00
33333,Gates,Lee,Thyroid,1000.00
33334,Johnson,Lee,Thyroid,1000.00
33335,Carter,Lee,Dental,100.00
Code so far for reference:
package Patient_Reports_Package;
/**
* Created by bzink on 8/28/2015.
*/
import javax.swing.*;
import java.io.*;
import java.util.StringTokenizer;
/**
* The Patient_Reports_File class reads the data file into an array, and then has a menu for 5 reports.
*/
class Patient_Reports {
private final int[] id = new int[100];
private final String[] patient = new String[100];
private final String[] doctor = new String[100];
private final String[] surgery = new String[100];
private final double[] cost = new double[100];
private int count = -1;
private int i;
public static void main (String[] args) {
int selection;
String report_number;
Patient_Reports patient = new Patient_Reports();
patient.start_system();
report_number = patient.menu();
selection = Integer.parseInt(report_number);
while (selection !=6) {
if (selection == 1) {
patient.allInformationReport();
} else if (selection == 2) {
patient.surgeryDoctorReport();
} else if (selection == 3) {
patient.surgeryTypeReport();
} else if (selection == 4) {
patient.doctorFeesReport();
} else if (selection == 5) {
patient.averageFeesReport();
}
report_number = patient.menu();
selection = Integer.parseInt(report_number);
}//while loop
patient.writeReports();
System.exit(0);
}//main
//Read Data File into Array
private void start_system() {
String newLine;
try {
//define a file variable for Buffered read
BufferedReader Patient_Reports = new BufferedReader(new java.io.FileReader("C:\\Users\\Brandon\\" +
"Downloads\\Patient_Reports_File\\patient.txt"));
//read lines in file until there are no more lines in the file to read
while ((newLine = Patient_Reports.readLine()) != null) {
//there is a "," between each data item in each line
StringTokenizer delimiter = new StringTokenizer(newLine, ",");
count = count + 1;
id[count] = Integer.parseInt(delimiter.nextToken());
patient[count] = delimiter.nextToken();
doctor[count] = delimiter.nextToken();
surgery[count] = delimiter.nextToken();
cost[count] = Double.parseDouble(delimiter.nextToken());
}//while loop
Patient_Reports.close();
}//end try
catch (IOException error) {
//there was an error on the file writing
System.out.println("Error on file read " + error);
}//end catch
}//end start_system
//Report Menu
private String menu () {
StringBuilder stringBuilder = new StringBuilder();
stringBuilder.append("Id ").append(" \n");
stringBuilder.append("Patient ").append(" \n");
stringBuilder.append("Doctor ").append(" \n");
stringBuilder.append("Surgery ").append(" \n");
stringBuilder.append("Cost ").append(" \n");
for (int i = 0; i < 6; i++) {
stringBuilder.append(i).append(" Name"+i).append('\n');
}
String startTag ="<font size='2' color='red'>";
String endTag = "</font>";
stringBuilder.append(startTag).append("Some content").append(endTag);
JOptionPane.showMessageDialog(null, stringBuilder.toString());
return stringBuilder.toString();
}//end menu\
/*
//Report Menu
private String menu() {
String report;
String Output = "Reports" + "\n" + "1. All_Information_Report" + "\n" +
"2. Surgeries_Doctor_Report" + "\n" +
"3. Surgeries_Type_Report" + "\n" +
"4. Doctor_Fees_Report" + "\n" +
"5. Average_Fees_Report" + "\n" +
"6. Exit" + "\n" +
" " + "\n" +
"Select a Report >";
report = JOptionPane.showInputDialog(null,
Output, "", JOptionPane.QUESTION_MESSAGE);
return report;
}//end menu\
*/
//Report containing all of the information
private void allInformationReport() {
System.out.println("All Information Report");
for (i = 0; i <= count; ++i) {
System.out.println(id[i] + " " + patient[i] + " " + doctor[i] + " " + surgery[i] + " " + cost[i] + " ");
}//for loop
}//end report
/* void selectDoctor()
{
//select doctor
String doctorOutput;
//int intNum=0,intNum1=0,i,x=-1;
count=count+1;
doctorOutput = "Enter the Doctor's Name";
doctor[count] =JOptionPane.showInputDialog(null,doctorOutput,
"",JOptionPane.QUESTION_MESSAGE);
}//end select doctor
//Start Doctor Menu
public static void doctorMenu (String[] args) {
int selection;
String doctorName;
Patient_Reports doctor = new Patient_Reports();
doctor.start_system();
doctorName = doctorMenu();
selection = Integer.parseInt(doctorName);
while (selection !=4) {
if (selection == 1) {
doctor.norrisSurgeries();
} else if (selection == 2) {
doctor.bondSurgeries();
} else if (selection == 3) {
doctor.leeSurgeries();
}
doctorName = doctorMenu();
selection = Integer.parseInt(doctorName);
}//while loop
doctor.writeReports();
System.exit(0);
}//End Doctor Menu
//Report on all surgeries by Dr. Norris
private void norrisSurgeries() {
System.out.println("Norris Surgeries Report");
for (i = 0; i <= count; ++i) {
System.out.println(doctor[i] + " " + surgery[i] + " ");
}//for loop
}//end report
//Report on all surgeries by Dr. Bond
private void bondSurgeries() {
System.out.println("Bond Surgeries Report");
for (i = 0; i <= count; ++i) {
System.out.println(doctor[i] + " " + surgery[i] + " ");
}//for loop
}//end report
//Report on all surgeries by Dr. Lee
private void leeSurgeries() {
System.out.println("Lee Surgeries Report");
for (i = 0; i <= count; ++i) {
System.out.println(doctor[i] + " " + surgery[i] + " ");
}//for loop
}//end report
*/
//Report on all surgeries of a specific doctor (prompt for the doctor)
private void surgeryDoctorReport() {
System.out.println("Surgeries Doctor Report");
for (i = 0; i <= count; ++i) {
System.out.println(id[i] + " " + patient[i] + " " + doctor[i] + " " + surgery[i] + " " + cost[i] + " ");
}//for loop
}//end report
/*
void selectSurgery()
{
//select surgery
String surgeryOutput;
//int intNum=0,intNum1=0,i,x=-1;
count=count+1;
surgeryOutput = "Enter the Surgery Type";
doctor[count] =JOptionPane.showInputDialog(null,surgeryOutput,
"",JOptionPane.QUESTION_MESSAGE);
}//end select surgery
*/
//Report on all surgeries of a specific type(Prompt for the surgery type)
private void surgeryTypeReport() {
System.out.println("Surgeries Type Report");
for (i = 0; i <= count; ++i) {
System.out.println(id[i] + " " + patient[i] + " " + doctor[i] + " " + surgery[i] + " " + cost[i] + " ");
}//for loop
}//end report
//Report on the total amount of fees paid to each doctor
private void doctorFeesReport() {
System.out.println("Doctor Fees Report");
for (i = 0; i <= count; ++i) {
System.out.println(id[i] + " " + patient[i] + " " + doctor[i] + " " + surgery[i] + " " + cost[i] + " ");
}//for loop
}//end report
//Report on the Average Fee
private void averageFeesReport() {
System.out.println("Average Fees Report");
for (i = 0; i <= count; ++i) {
System.out.println(id[i] + " " + patient[i] + " " + doctor[i] + " " + surgery[i] + " " + cost[i] + " ");
}//for loop
}//end report
//Store Data File in Array
private void writeReports()
{
try {
BufferedWriter Patient_Reports = new BufferedWriter(new java.io.FileWriter("patient_out.txt"));
for (i = 0; i <= count; ++i) {
//put "," between each data item in the file
Patient_Reports.write(id[i] + "," + patient[i] + "," + doctor[i] + "," +
surgery[i] + "," + cost[i] + ",");
//write a new line in the file
Patient_Reports.newLine();
}//for loop
Patient_Reports.close();
}//end try
catch (IOException error) {
//there was an error on the write to file
System.out.println("Error on file write " + error);
}//end error
}//end write_reports
}
'

Use String or StringBuilder or StringBuffer to do this. But instead of String use either StringBuilder or StringBuffer. Since for String, you need some extra objects for String manipulation.
Ex:
StringBuilder sb = new StringBuilder();
sb.append("Id ").append(" Name\n");
for (int i = 0; i < 10; i++) {
sb.append(i).append(" Name"+i).append('\n');
}
JOptionPane.showMessageDialog(null, sb.toString());
Use HTML tags to produce better formatted results like <font>, <table>, etc.
Ex:
String startTag ="<font size='2' color='red'>";
String endTag = "</font>";
sb.append(startTag+"Some content"+endTag);

I am currently taking an AP Computer Science class in my school and I ran into a little trouble with one of my projects! The project requires me to create a calculator that can evaluate an expression and then solve it. I have got most of that down, but I ran into a little trouble because my teacher asked me to use a while loop to continuously ask for input and display the answer, and I am stuck on that. To end the program the user has to type in "quit" and I can't use system.exit() or any cheating thing like that, the program has to just run out of code. Does anyone have any tips?
import java.util.*;
public class Calculator {
public static void main(String[] args) {
System.out.println("Welcome to the AP Computer Science calculator!!");
System.out.println();
System.out.println("Please use the following format in your expressions: (double)(space)(+,-,*,/...)(space)(double)");
System.out.println("or: (symbol)(space)(double)");
System.out.println();
next();
}
public static void next() {
Scanner kb = new Scanner(System.in);
System.out.print("Enter an expression, or quit to exit: ");
String expression = kb.nextLine();
next3(expression);
}
public static void next3(String expression) {
while (!expression.equals("quit")) {
next2(expression);
next();
}
}
public static void next2(String expression) {
if (OperatorFor2OperandExpressions(expression).equals("+")) {
System.out.println(FirstOperandFor2OperandExpressions(expression) + " " + OperatorFor2OperandExpressions(expression) + " " + SecondOperandFor2OperandExpressions(expression) + " = " + (FirstOperandFor2OperandExpressions(expression) + SecondOperandFor2OperandExpressions(expression)));
}
else if (OperatorFor2OperandExpressions(expression).equals("*")) {
System.out.println(FirstOperandFor2OperandExpressions(expression) + " " + OperatorFor2OperandExpressions(expression) + " " + SecondOperandFor2OperandExpressions(expression) + " = " + (FirstOperandFor2OperandExpressions(expression) * SecondOperandFor2OperandExpressions(expression)));
}
else if (OperatorFor2OperandExpressions(expression).equals("-")) {
System.out.println(FirstOperandFor2OperandExpressions(expression) + " " + OperatorFor2OperandExpressions(expression) + " " + SecondOperandFor2OperandExpressions(expression) + " = " + (FirstOperandFor2OperandExpressions(expression) - SecondOperandFor2OperandExpressions(expression)));
}
else if (OperatorFor2OperandExpressions(expression).equals("/")) {
System.out.println(FirstOperandFor2OperandExpressions(expression) + " " + OperatorFor2OperandExpressions(expression) + " " + SecondOperandFor2OperandExpressions(expression) + " = " + (FirstOperandFor2OperandExpressions(expression) / SecondOperandFor2OperandExpressions(expression)));
}
else if (OperatorFor2OperandExpressions(expression).equals("^")) {
System.out.println(FirstOperandFor2OperandExpressions(expression) + " " + OperatorFor2OperandExpressions(expression) + " " + SecondOperandFor2OperandExpressions(expression) + " = " + Math.pow(FirstOperandFor2OperandExpressions(expression),SecondOperandFor2OperandExpressions(expression)));
}
else if (OperatorFor1OperandExpressions(expression).equals("|")) {
System.out.println(OperatorFor1OperandExpressions(expression) + " " + OperandFor1OperatorExpressions(expression) + " = " + Math.abs(OperandFor1OperatorExpressions(expression)));
}
else if (OperatorFor1OperandExpressions(expression).equals("v")) {
System.out.println(OperatorFor1OperandExpressions(expression) + " " + OperandFor1OperatorExpressions(expression) + " = " + Math.sqrt(OperandFor1OperatorExpressions(expression)));
}
else if (OperatorFor1OperandExpressions(expression).equals("~")) {
double x = 0.0;
System.out.println(OperatorFor1OperandExpressions(expression) + " " + OperandFor1OperatorExpressions(expression) + " = " + (Math.round(OperandFor1OperatorExpressions(expression))+ x));
}
else if (OperatorFor1OperandExpressions(expression).equals("s")) {
System.out.println(OperatorFor1OperandExpressions(expression) + " " + OperandFor1OperatorExpressions(expression) + " = " + Math.sin(OperandFor1OperatorExpressions(expression)));
}
else if (OperatorFor1OperandExpressions(expression).equals("c")) {
System.out.println(OperatorFor1OperandExpressions(expression) + " " + OperandFor1OperatorExpressions(expression) + " = " + Math.cos(OperandFor1OperatorExpressions(expression)));
}
else if (OperatorFor1OperandExpressions(expression).equals("t")) {
System.out.println(OperatorFor1OperandExpressions(expression) + " " + OperandFor1OperatorExpressions(expression) + " = " + Math.tan(OperandFor1OperatorExpressions(expression)));
}
}
public static double FirstOperandFor2OperandExpressions(String expression) {
String[] tokens = expression.split(" ");
String OperandOrOperator = tokens[0];
double y = Double.parseDouble(OperandOrOperator);
return y;
}
public static double SecondOperandFor2OperandExpressions(String expression) {
String[] tokens = expression.split(" ");
String OperandOrOperator = tokens[2];
double y = Double.parseDouble(OperandOrOperator);
return y;
}
public static String OperatorFor2OperandExpressions(String expression) {
String[] tokens = expression.split(" ");
String OperandOrOperator = tokens[1];
return OperandOrOperator;
}
public static String OperatorFor1OperandExpressions(String expression) {
String[] tokens = expression.split(" ");
String OperandOrOperator = tokens[0];
return OperandOrOperator;
}
public static double OperandFor1OperatorExpressions(String expression) {
String[] tokens = expression.split(" ");
String OperandOrOperator = tokens[1];
double y = Double.parseDouble(OperandOrOperator);
return y;
}
public static boolean QuitFunction(String expression) {
if (expression.equalsIgnoreCase("quit")) {
System.out.println("Goodbye!");
return false;
}
else {
return true;
}
}
}

Take a look at this code. I think this might help you in the right direction. It's similar to what you have already written except it eliminates the need for method calls in your while loop.
Scanner input = new Scanner(System.in);
while (!input.hasNext("quit")) {
String expression = input.nextLine(); // gets the next line from the Scanner
next2(expression); // process the input
}
// once the value "quit" has been entered, the while loop terminates
System.out.println("Goodbye");
Writing it this way drastically cleans up your code and prevents a new declaration of Scanner kb = new Scanner(System.in); each time an input is processed.