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write to separate columns in csv

I am trying to write 2 different arrays to a csv. The first one I want in the first column, and second array in the second column, like so:
array1val1 array2val1
array1val2 array2val2
I am using the following code:
String userHomeFolder2 = System.getProperty("user.home") + "/Desktop";
String csvFile = (userHomeFolder2 + "/" + fileName.getText() + ".csv");
FileWriter writer = new FileWriter(csvFile);
final String NEW_LINE_SEPARATOR = "\n";
FileWriter fileWriter;
CSVPrinter csvFilePrinter;
CSVFormat csvFileFormat = CSVFormat.DEFAULT.withRecordSeparator(NEW_LINE_SEPARATOR);
fileWriter = new FileWriter(fileName.getText());
csvFilePrinter = new CSVPrinter(fileWriter, csvFileFormat);
try (PrintWriter pw = new PrintWriter(csvFile)) {
pw.printf("%s\n", FILE_HEADER);
for(int z = 0; z < compSource.size(); z+=1) {
//below forces the result to get stored in below variable as a String type
String newStr=compSource.get(z);
String newStr2 = compSource2.get(z);
newStr.replaceAll(" ", "");
newStr2.replaceAll(" ", "");
String[] explode = newStr.split(",");
String[] explode2 = newStr2.split(",");
pw.printf("%s\n", explode, explode2);
}
}
catch (Exception e) {
System.out.println("Error in csvFileWriter");
e.printStackTrace();
} finally {
try {
fileWriter.flush();
fileWriter.close();
csvFilePrinter.close();
} catch (IOException e ) {
System.out.println("Error while flushing/closing");
}
}
However I am getting a strange output into the csv file:
[Ljava.lang.String;#17183ab4
I can run
pw.printf("%s\n", explode);
pw.printf("%s\n", explode2);
Instead of : pw.printf("%s\n", explode, explode2);
and it prints the actual strings but all in one same column.
Does anyone know how to solve this?

1.Your explode and explode2 are actually String Arrays. You are printing the arrays and not the values of it. So you get at the end the ADRESS of the array printed.
You should go through the arrays with a loop and print them out.
for(int i = 0; i<explode.length;++i) {
pw.printf("%s%s\n", explode[i], explode2[i]);
}
2.Also the method printf should be look something like
pw.printf("%s%s\n", explode, explode2);
because youre are printing two arguments, but in ("%s\n", explode, explode2) is only one printed.
Try it out and say if it worked

After these lines:
newStr.replaceAll(" ", "");
newStr2.replaceAll(" ", "");
String[] explode = newStr.split(",");
String[] explode2 = newStr2.split(",");
Use this code:
int maxLength = Math.max(explode.length, explode2.length);
for (int i = 0; i < maxLength; i++) {
String token1 = (i < explode.length) ? explode[i] : "";
String token2 = (i < explode2.length) ? explode2[i] : "";
pw.printf("%s %s\n", token1, token2);
}
This also cover the case that the arrays are of different length.

I have removed all unused variables and made some assumptions about content of compSource.
Moreover, don't forget String is immutable. If you just do "newStr.replaceAll(" ", "");", the replacement will be lost.
public class Tester {
#Test
public void test() throws IOException {
// I assumed compSource and compSource2 are like bellow
List<String> compSource = Arrays.asList("array1val1,array1val2");
List<String> compSource2 = Arrays.asList("array2val1,array2val2");
String userHomeFolder2 = System.getProperty("user.home") + "/Desktop";
String csvFile = (userHomeFolder2 + "/test.csv");
try (PrintWriter pw = new PrintWriter(csvFile)) {
pw.printf("%s\n", "val1,val2");
for (int z = 0; z < compSource.size(); z++) {
String newStr = compSource.get(z);
String newStr2 = compSource2.get(z);
// String is immutable --> store the result otherwise it will be lost
newStr = newStr.replaceAll(" ", "");
newStr2 = newStr2.replaceAll(" ", "");
String[] explode = newStr.split(",");
String[] explode2 = newStr2.split(",");
for (int k = 0; k < explode.length; k++) {
pw.println(explode[k] + "\t" + explode2[k]);
}
}
}
}
}

Counting words from a file

for this program I have to write I'm given an input file of strings that has a line (or lines) of text, for example: "The high HIGH cat High jumped (WOW 6SOFT)". From this line I have to scan the file, count the number of times a word appears (regardless of capitalization), and then output it to a formatted file. If a digit comes before a word, the word should not be counted. The format has to be started with the count right justified in three spaces, followed by another space, followed by the word counted in lower case.
package InClass;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Scanner;
public class CountWords {
public static void main(String[] args) {
try {
File inputFile = new File("input.txt");
Scanner scanner = new Scanner(inputFile);
File outputFile = new File("output.txt");
PrintWriter writer = new PrintWriter(outputFile);
boolean next = scanner.hasNext();
ArrayList<String> inputWords = new ArrayList<String>();
ArrayList<String> outputWords = new ArrayList<String>();
while (next) { // Adds all the strings to an array list
inputWords.add(scanner.next());
for (int i = 0; i < inputWords.size(); i++) {
inputWords.get(i).toLowerCase();
}
}
while (next) {
for (int i = 0; i < inputWords.size(); i++) {
String word = inputWords.get(i);
int count = 1;
if (!Character.isDigit(word.charAt(0))) {
outputWords.add(inputWords.get(i));
if (outputWords.contains(word)) {
count++;
}
} else {
inputWords.remove((i));
}
for (int j = 0; i < outputWords.size(); j++) {
word = outputWords.get(i);
writer.printf("%3s" + "%1s\n", count, word);
}
}
}
scanner.close();
writer.close();
} catch (FileNotFoundException e) {
}
}
}
My tester file is giving me an error saying there is a NoSuchElementException for only one of the tester classes, which is testing two words. Here is the test class giving the error"
#Test
public void testTwoWords() {
try {
File inputFile = new File(INPUT);
File outputFile = new File(OUTPUT);
// If assert fails it is (usually) because the file was (wrongly)
// left open in an earlier run.
// Using a file manager application (e.g. explorer), go to project
// directory and delete it.
// Make sure that your program closes these files before ending.
if (inputFile.exists()) {
assertTrue("Your program left \"" + INPUT
+ "\" open in a previous test.", inputFile.delete());
}
if (outputFile.exists()) {
assertTrue("Your program left \"" + OUTPUT
+ "\" open in a previous test.", outputFile.delete());
}
// create INPUT file
PrintWriter input = new PrintWriter(inputFile);
input.println("King");
input.println("");
input.println("");
input.println("");
input.println("hill");
input.close();
// invoke program
CountWords.main(null);
// verify OUTPUT file exists and is empty
assertTrue("Output file doesn't exist", outputFile.exists());
Scanner output = new Scanner(outputFile);
String actual = output.nextLine();
assertEquals("Incorrect result", " 1 king", actual);
actual = output.nextLine();
assertEquals("Incorrect result", " 1 hill", actual);
assertFalse("There should be no more data", output.hasNext());
output.close();
// delete I/O files
assertTrue("Input file could not be deleted", inputFile.delete());
assertTrue("Output file could not be deleted", outputFile.delete());
} catch (IOException e) {
fail("No exception should be thrown");
}
}
Finally, my other testers are saying "Your program left "input.txt" open in a previous test". Any idea why? Thank you tons in advance!

The for loop for your outputWords is using the i loop counter instead of j.
for (int j = 0; i < outputWords.size(); j++) {
word = outputWords.get(i);
writer.printf("%3s" + "%1s\n", count, word);
}
Change that to
for (int j = 0; i < outputWords.size(); j++) {
word = outputWords.get(j);//NEED TO USE J HERE
writer.printf("%3s" + "%1s\n", count, word);
}
The reason the other tests are failing is because you are apparently supposed to delete the output files after each test is run.

Appending text on a character interval

I am trying to write a program where the participant communicates with the program (I/O) via a console. Trick is, the console is part of a GUI, because I need the program to run off of a executable jar file. I append text with a scrollable text field, like so
textArea.append(printChar);
I give the method a String to work with, and it uses a nested for loop to take it, char by char, and append each Char (using string.substring()).
My problem is that it freezes up the entire time its supposed to be printing, then just displays it all. I don't know why, because I tested it using System.out.print, and it worked exactly as I wanted. So something is different about appending and printing. Any ideas?
Also, I am using Thread.Sleep(100) for my wait time.
public void actionPerformed(ActionEvent evt) {
if (!preforming){
preforming = true;
String input = textField.getText(); //Text from Input
textArea.append(dungeon.name + ": " + input + newline); //Add "text" to bottom of console
String[] output = dungeon.action(input);
//print everything in array output, char by char, with 2-3 seconds after each
for (int i = 0; i < output.length; i++){
String printThis = output[i];
if (printThis.length() > 0){
for (int j = 0; j < printThis.length(); j++){
String printChar = printThis.substring(j, j+1);
textArea.append(printChar);
//System.out.print(printChar);
try{
Thread.sleep(5);
} catch (InterruptedException e) {
System.out.print("Error ");
}
/*try { //useless
Thread.sleep(200);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}*/
}
}
textArea.append("" + newline);
}
//cleaning up input bar
textField.setText("");
textField.selectAll();
//Make sure the new text is visible, even if there
//was a selection in the text area.
textArea.setCaretPosition(textArea.getDocument().getLength());
preforming = false;
}
}

I've edited my answer as you are showing more of your codes. Since, there is an outer loop in your code, I just included it inside the run method of timer in this new edit. And also I don't have the code for the dungeon so I just temporarily replace it with constant values so the program can run in my test.
public void actionPerformed(ActionEvent evt) {
java.util.Timer timer = new java.util.Timer();
timer.schedule(new java.util.TimerTask() {
public void run() {
if (!preforming){
preforming = true;
String newline = "\n";
String dungeonName = "Star Light";
String input = textField.getText(); //Text from Input
textArea.append(dungeonName + ": " + input + newline); //Add "text" to bottom of console
String[] output = {
"Twinkle twinkle little star.",
"How I wonder what you are.",
"Up above the world so high."
};
//print everything in array output, char by char, with 2-3 seconds after each
for (int i = 0; i < output.length; i++){
String printThis = output[i];
if (printThis.length() > 0){
for (int j = 0; j < printThis.length(); j++){
String printChar = printThis.substring(j, j+1);
textArea.append(printChar);
//System.out.print(printChar);
try{
Thread.sleep(25);
} catch (InterruptedException e) {
System.out.print("Error ");
}
/*try { //useless
Thread.sleep(200);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}*/
}
}
textArea.append("" + newline);
}
//cleaning up input bar
textField.setText("");
textField.selectAll();
//Make sure the new text is visible, even if there
//was a selection in the text area.
textArea.setCaretPosition(textArea.getDocument().getLength());
preforming = false;
}
}
}, 1);
}

Java - NumberFormatException at linear search

I am having this issue with the NumberFormatException in my program. Basically, I am asked to read a .csv file separated by ; and it looks like this:
// Column Explanation (not in .csv file)
id; Summary; Number; Employee1; Employee2; ....... Employee7;
"1";"Sony";"1600";"Markos";"Nikos";"Antonis";"Nikolas";"Vaggelis";"Markos";"Thanasis";
"2";"HP";"1000";"Marios";"Dimitra";"Nikolia";"Spiros";"Thomas";"Kostas";"Manolis";
"3";"Dell";"1100";"Antonis";"Aggelos";"Baggelis";"Nikos";"Kuriakos";"Panagiotis";"Rafail";
"4";"Acer";"2000";"Marina";"Aggelos";"Spiros";"Marinos";"Xristos";"Antreas";"Basilis";
What I have already done is create a String 2-d array or the .csv file called temp_arr and I am asked to write a method that will run a linear search by id and return that company. So here is the thing.
At first, I thought I should convert the input key from int -> String since my temp_arr is a String and compares the strings (which at that time they would be int but read as Strings) using temp_arr[value][value2].equals(string_key). But I had a NullPointerException.
Then I thought I should better convert my Id's from the temp_arr from String -> Int and then compare with the integer key using == operand. This action returned me a NumberFormatException.
The process is this:
System.out.println("Enter id :");
Scanner input = new Scanner(System.in);
int item = input.nextInt(); // read the key which is an Integer
int id_int; // temp_arr is String and item is int, must convert ids from String -> int
for (int i = 0; i < temp_arr.length; i++)
{
id_int = Integer.parseInt(temp_arr[i][0]); // Convert from String to int
if (id_int == item) // If the Array's Id's are == item
{
System.out.println(item+" is present at location " + (i+1) );
break;
}
if (i == temp_arr.length)
System.out.println(item + " does not exist");
}
My error appears at line 7 and I do not know why.
Read File process:
String csvFile = "sam.csv"; // .csv file to be placed in the project file!
BufferedReader br = null; // ini
String line = "",cvsSplitBy = ";"; // columns asked to be split by ";"
String[] arr = null;
String[][] temp_arr = new String[1000][10];
int temp = 0;
try
{
br = new BufferedReader(new FileReader(csvFile)); //start reading the file
while ((line = br.readLine()) != null) // while the line has words
{
arr = line.split(cvsSplitBy); // creating the array
System.out.println(arr[0] + "\t" + arr[1] + "\t" + arr[2] + "\t" + arr[3] + "\t" + arr[4] + "\t" + arr[5] + "\t" + arr[6] + "\t" + arr[7] + "\t" + arr[8] + "\t" + arr[9] );
for (int i = 0; i<=9; i++)
{
temp_arr[temp][i] = arr[i]; // temp_arr represents (is a copy of) the .csv file
}
temp++;
}
} catch (FileNotFoundException e)
{
e.printStackTrace();
} catch (IOException e)
{
e.printStackTrace();
} finally
{
if (br != null)
{
try
{
br.close();
} catch (IOException e)
{
e.printStackTrace();
}
}
}
System.out.println("Done!\n");
Output (Image) :
Line 106 which is causing the issue is :
id_int = Integer.parseInt(temp_arr[i][0]); // Convert from String to int

Your issue is that your Integer.parseInt() is trying to parse a "2" WITH QUOTATION MARKS. That's the problem.
A quick solution would be to replace this line:
temp_arr[temp][i] = arr[i];
To this:
temp_arr[temp][i] = arr[i].replaceAll("\"", "");
Anyway, I'd like to suggest using a different data structure for your case, because I've done something like this before for a client. Have you ever heard of HashMaps? You can do something like a HashMap with an int key and String[] values to store your data in, and the key can be your id_int. Maybe you can try this implementation next time. It's a lot more elegant.
Hope I was able to help!
Cheers,
Justin

Would help if you also posted some of your data file and how you are reading it in.
But, my guess from what is presented is if you add System.out.println(temp_arr[i][0]) prior to the 7th line or run this code through a debugger you will see that temp_arr[i][0] is not an integer value as that is what the error is telling you.

Unable to open file using File f = new File(file_pth);

I am trying to open a file by drag and drop onto JTextField but i always get the error.
Heres my code
public void drop(DropTargetDropEvent dtde) {
String str4=null;
try {
JTextArea comp = null;
if(Switchtab==2)
comp=textarea1;
if(Switchtab==3)
comp=textarea2;
if(Switchtab==4)
comp=textarea3;
if(Switchtab==1)
comp=textarea4;
// Ok, get the dropped object and try to figure out what it is
Transferable tr = dtde.getTransferable();
DataFlavor[] flavors = tr.getTransferDataFlavors();
for (int i = 0; i < flavors.length; i++) {
System.out.println("Possible flavor: "
+ flavors[i].getMimeType());
// Check for file lists specifically
if (flavors[i].isFlavorJavaFileListType()) {
// Great! Accept copy drops...
dtde.acceptDrop(DnDConstants.ACTION_COPY);
// comp.setText("Successful file list drop.\n\n");
// And add the list of file names to our text area
java.util.List list = (java.util.List) tr
.getTransferData(flavors[i]);
for (int j = 0; j < list.size(); j++) {
//wcomp.append(list.get(j) + "\n");
str4=list.get(j)+"\n";
}
// Replace '\' with '/'
file_pth = str4.replaceAll("\\\\","/" );
System.out.println(str4.replaceAll("\\\\","/" ));
//Open the file
try {
File f = new File(file_pth);
FileInputStream fobj = new FileInputStream(f);
int len = (int) f.length();
str4 = "";
for (int j = 0; j < len; j++) {
char str5 = (char) fobj.read();
str4 = str4 + str5;
}
comp.setText(str4);
setTitle(str4);
} catch (Exception e) {
System.out.println("Caught::" + e);
}
// If we made it this far, everything worked.
dtde.dropComplete(true);
return;
}
}
// Hmm, the user must not have dropped a file list
System.out.println("Drop failed: " + dtde);
dtde.rejectDrop();
} catch (Exception e) {
e.printStackTrace();
dtde.rejectDrop();
}
}
I even tried replacing backslash with double backslash and forward slash but still i get this error
Possible flavor: application/x-java-file-list; class=java.util.List
C:/kevin_java/file io/DemoIO.java
Caught::java.io.FileNotFoundException: C:\kevin_java\file io\DemoIO.java
(The filename, directory name, or volume label syntax is incorrect)
The output doesnt show the replaced string.
It shows the previous string with single backslash.

finally i got my answer.
Simple solution
java.util.List list = (java.util.List) tr
.getTransferData(flavors[i]);
for (int j = 0; j < list.size(); j++) {
str4=list.get(j).toString();
}
File f = new File(str4);
FileInputStream fobj = new FileInputStream(f);
...
...
..

Edit
From the javadoc for isFlavorJavaFileListType,
Returns true if the DataFlavor specified represents a list of file objects.
Therefor,
FileInputStream fobj = new FileInputStream(list.get(list.length()-1));