ArrayIndexOutOfBounds error

Question

Hi all, when running the following code, I get an ArrayIndexOutOfBounds: 255 error. I should note that getHist() returns an int[3][255]. I'm sure there's something simple that I should be doing, but I don't know what it is. Any ideas?
private void saveFile() {
        BufferedImage bi = leftPanel.img;
        int[][] image_data = getHist(bi);
                //new int[3][256];
        //image_data = getHist(bi);
        //System.out.println(image_data.length);
        JFileChooser saveChoose = new JFileChooser();
        int result = saveChoose.showSaveDialog(this);
        if (result == JFileChooser.CANCEL_OPTION) return;
        if(result == JFileChooser.APPROVE_OPTION)
        try{
            FileWriter fw = new FileWriter(saveChoose.getSelectedFile());
            BufferedWriter bw = new BufferedWriter(fw);
           for(int i = 0; i < image_data.length; i++){
               for(int j = 0; j < image_data.length; j++){
//System.out.println(image_data[i].length);
if(j == (image_data[i].length - 1)){
//System.out.println("Condition ok " + image_data[i].length );
bw.write(String.valueOf(image_data[j][i]) );
System.out.println("Data ok");
bw.newLine();
else{
bw.write( String.valueOf(image_data[i]) + "\t");
bw.close();
}catch(Exception e){
System.out.println("Error: " + e);
Thanks,
Joe

Answer 1

I generalized my example so it can write to System.out or a BufferedWriter:
import java.io.*;
public class Example {
    static void print(Appendable out, int[][] m) throws IOException {
        String lineSeparator = System.getProperty("line.separator");
        for(int i=0; i<m.length; ++i) {
            for (int j=0; j < m.length; j++) {
out.append(String.valueOf(m[i][j])).append("\t");
out.append(lineSeparator);
public static void main(String[] args) throws IOException {
int[][] data = {
{0,2,4,6,8},
{1,3,5,7,9},
print(System.out, data);
BufferedWriter bw = new BufferedWriter(new FileWriter("junk.txt"));
try {
print(bw, data);
} finally {
bw.close();