import java.io.File;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.FileInputStream;
import java.io.IOException;
import javax.swing.JFileChooser;

/**
 * Solution code for Project 2a
 * Text File Dumper
 * User chooses a file
 * The program then reads each line and displays in on the console
 * The program should never abort, even if a bad file is chosen,
 *          or if the file has an error.
 * In case of an error, the program should display information about the error,
 *  and then terminate (use System.exit(0))
 *
 */
public class TextFileDumper {
    
    public static void main(String[] args) {
        String fullFileName = getFilePath();
        System.out.println("Contents of file " + fullFileName);
        
        //Create an appropriate stream or reader
        FileInputStream fistream;
        BufferedReader inReader = null;
        try {
        fistream = new FileInputStream(fullFileName);
        inReader = new BufferedReader(new InputStreamReader (fistream));
        } catch (IOException e) {
            System.out.println("Couldn't open file " + fullFileName);
            System.out.println(e);
            System.exit(0);
        }
        String currentLine = null;
        //Do for each line on the file
        do {
            //read a line
            try {
            currentLine = inReader.readLine(); 
            } catch (IOException e) {
                System.out.println("Unexpected exception while reading file: " + e);
                currentLine = null; //will cause loop to end
            }
            if (currentLine != null) {
                //print it to the console
                System.out.println(currentLine);
            }
        }        
        while (currentLine != null);
        
        System.out.println("Dump of " + fullFileName + " complete.");
        System.exit(0); //in case there's a thread running somewhere
    } //end main
    
    /** Let user choose a file
     */
    public static String getFilePath() {
        JFileChooser chooser = new JFileChooser(); 
        int resultOfShow = chooser.showDialog(null, 
                            "Choose a text file");
        if (resultOfShow == JFileChooser.APPROVE_OPTION) {
            return chooser.getSelectedFile().getAbsolutePath();
        } else {
            //user must have canceled
            throw new RuntimeException("User canceled the file selection procedure");
        }
    }
    
} //end TextFileDumper