Al Dunne

Hi Rob,

Thanks for that. So does that mean all I'll need in my code is:

import java.net.URL; public void playSound (int activeSound) audio = AudioSystem.getAudioInputStream(this.getClass().getResource (activeSound+"db.wav")); clip = AudioSystem.getClip(); clip.open(audio); clip.start(); clip.loop(Clip.LOOP_CONTINUOUSLY);

Thanks a lot for your help Ritchie. Much appreciated.

Campbell Ritchie wrote:That code doesn’t change the state of the List at all. What it does, however, is get a reference to every Check Box in the List, and the next statement changes the state of that check box. My version did it all in one line.

Am I right then in saying that "JCheckBox check = (JCheckBox) checkBoxState.get(i);" makes 'check' be a reference to checkBoxState[i] so that if you change the state of 'check' (as the bit after that code does) it will change the state of checkBoxState[i].

This is the part that I don't understand as in the most part all I've been working with is primitives where if you say int num = otherNum (another int) then the value of num will be the same as otherNum. Whereas if you applied the logic from above writing int num = otherNum would make the value in OtherNum the same as num.

I'm vaguely remebering something about object references??? If you make an object1 ref = object2, am I right in saying that the object 1 is just a reference to object2 rather than an object itself. Confusing myself now.

Yes, the saveBeatBox method is at Line 236 above. It just saves a boolean [] called savedCheckBoxState.

Still don't understand how this line changes the state of checkBoxState[i]. Is it not always that the thing on the left of the = will become what's on the right?

JCheckBox check = (JCheckBox) checkBoxState.get(i);

The code is from the second edition of HeadFirst which I think is the latest version.

Thanks for taking the time.

Hi all,

I've a problem with creating a jar file that's melting my brain. I've been at it for the last 3 days and cannot solve. I've tried pretty much everything. If anyone can help, please do.

So originally I had a File [] called soundFile that is going to store 9 files. I had a loop to import the 9 wav files. These wav files were called 0db.wav, 1db.wav etc etc and to get the code to work, I had to put these files inside my Version 4 folder (see image attached - Method 1 folder).

My original code for loading was as follows:

Code:
for (int i = 0; i < 9; i++){

soundFile [i] = new File (i + "db.wav");
}



This worked fine when I ran the project in NetBeans. However, a couple of days ago I tried to create the jar file and the section that played the sounds did not work i.e. did not play the sounds. From looking at it, when I told NetBeans to load the file it looked in the Version 4 folder (see image attached - Method 1 folder).

I then looked around everywhere to see what the problem was. I ended up getting the jar file working by hard-coding in a directory address but as you might guess, when I changed computer it stopped working.

So then after getting advice from other forums I tried numerous things. The most promising was to move the wav files into the rubberduckssoundproject folder which is inside the src folder. This folder rubberduckssoundproject contains all our other code in the project. The code for loading the wav files was then:

Code:
for (int i = 0; i < 9; i++){
try{
soundFile [i] = new File (this.getClass().getResource (i+"db.wav").toURI());
}
catch (Exception fileError){
System.out.println("Sorry but there's a problem loading your files into an array");
fileError.printStackTrace();
}

System.out.println("The soundfile located at soundFile "+i+" has the following path:"+soundFile[i].getAbsolutePath());
}


So this worked when the project was run in NetBeans. The path it returned for the files was ".........\Version 4\build\classes\rubberduckssoundproject\0db.wav"

This looked good to me as I think (I'm fairly new to Java) the jar files gets built from the build folder???

However, now when I clean and build, a jar file gets created but when I go to click this jar nothing happens. Then when I go back into the project folder it will not let me delete the jar file. It keeps saying "The action can't be completed because the file is open in Java (TM) Platform SE binary. This leads me to believe there's some sort of infinite loop or something being created?

I've thought about creating InputStreams and passing them to the
Code:
audio = AudioSystem.getAudioInputStream(soundFile[activeSound]);

The problem with this is I need an array of InputStreams and NetBeans will not let me do this. Can't remember exactly why, but it wouldn't. If anyone needs to know what it said I can try it again.

Please, please, please help if you can. I'm on the verge of giving up and I really don't want to.

Thanks a mil.

Al.

Campbell Ritchie wrote:
What you are doing is going through a list of check boxes, and setting their selected-ness (grammar!) to match the value in the parallel boolean[] array.

But can you tell me how this actually happens. I understand that line 265 makes the boolean [] loadCheckBoxState = the boolean [] read from the saved file (object cast back to a boolean []).

But whay I don't understand is how this then changes the state of the boolean [] "ArrayList <JCheckBox> checkBoxState" that gets run through the buildTrackAndStart method (Line 106).

So the line to adjust this has to be Lines 272 - 280
for (int i = 0; i < 256; i++){ JCheckBox check = (JCheckBox) checkBoxState.get(i); if (loadCheckBoxState[i]){ check.setSelected(true); } else{ check.setSelected(false); } }

I think it must be Line 2 from the little snippet above that is changing the state of checkBoxState[i].
To me this reads, new JCheckBox check = whatever is stored in checkBoxState [i] but I'm probably wrong and this actually means make whatever is in checkBoxState = to whatever gets put into 'check'.
Can anyone clarify this?

This is code from the HeadFirst Java book (slightly modified by me). If there's bad coding, it's their fault.

Sorry about the delay getting back also. I have another problem in NetBeans that has been sucking up my time. Still haven't solved it. Relates to jar files. I might stick it up here now aswell.

Thanks Ritchie. Can anyone help with line 14 of original code posting / line 273 of full code posting?

How exactly is this changing the checkBoxState arraylist?

Al.

It's an ArrayList of type JCheckBox. Here's my full cose (sorry about all the comments, it was me trying to understand each step). I'd really like to understand how the file import is altering the state of the checkBoxState ArrayList. Again, any help much appreciated. Al.

import java.awt.*; import javax.swing.*; import javax.sound.midi.*; import java.util.*; import java.awt.event.*; import java.io.*; public class BeatBox extends JPanel{ JPanel containerPanel; JPanel checkBoxPanel; JPanel instrumentNamePanel; ArrayList <JCheckBox> checkBoxState; Sequencer beatSequencer; Sequence beatSequence; Track beatTrack; JFrame containerFrame; /* @reference: Head First Java, Second Edition, Sierra K & Bates B, 2005. Create an array of Strings to hold the name of each instrument*/ String [] instrumentNames = {"Bass Drum", "Closed Hi-Hat", "Open Hi-Hat", "Acoustic Snare", "Crash Symbol", "Hand Clap", "High Tom", "Hi Bongo", "Maracas", "Whistle", "Low Conga", "Cowbell", "Vibraslap", "Low-mid Tom", "High Agogo", "Open Hi Conga"}; /* @ Reference: Head First Java, Second Edition, Sierra K & Bates B, 2005. // Create an array to hold the midi key for each instrument. These numbers are specified in the javax.sound.midi package */ int [] instruments = { 35, 42, 46, 38, 49, 39, 50, 60, 70, 72, 64, 56, 58, 47, 67, 63}; // @author Alan Dunne, x11105160 public BeatBox(){ // Create the container panel and give it some borders BorderLayout layout = new BorderLayout(); containerPanel = new JPanel (layout); // containerPanel.setBorder((BorderFactory.createEmptyBorder(1, 1, 1, 1))); containerPanel.setBounds(0, 0, 417, 379); /* Create the ArrayList of type JCheckBox that's going to hold the state of all the check boxes i.e. selected or not*/ checkBoxState = new ArrayList <JCheckBox>(); / Create the Panel to hold the instrument names and tell it to stack on the Y axis i.e. down. */ GridLayout alan = new GridLayout(16, 1); instrumentNamePanel = new JPanel(alan); alan.setVgap(1); // Populate the instrument name box using a loop to take strings from the String [] instrumentNames for (int i = 0; i<instrumentNames.length; i++){ instrumentNamePanel.add(new Label (instrumentNames[i])); } // Add the instruments name box to the container panel containerPanel.add(BorderLayout.WEST, instrumentNamePanel); // Create a 16 x 16 grid layout for the checkBoxePanel GridLayout grid = new GridLayout (16, 16); grid.setHgap(-1); grid.setVgap(1); // Create the checkBoxePanel checkBoxPanel = new JPanel (grid); // Add the checkBoxPanel to the container panel containerPanel.add(BorderLayout.CENTER, checkBoxPanel); /* Create the checkboxes, add their state to the checkBoxState ArrayList and add them to the checkBoxPanel. Do by using a loop to create 256 checkboxes called c but adding each one to a different place in the ArrayList. It also adds 256 checkboxes called c to each of the positions in the grid layout (checkBoxPanel). */ for (int i = 0; i < 256; i++){ JCheckBox c = new JCheckBox(); c.setSelected(false); checkBoxState.add(c); checkBoxPanel.add(c); } // Call the set setUpMidi method to ready the track setUpMidi(); // Add the container panel to the BeatBox class panel. Set the BeatBox class panel to null layout. setLayout(null); add(containerPanel); } // @reference: Head First Java, Second Edition, Sierra K & Bates B, 2005. // Set up midi sequencer, sequence and track method. public void setUpMidi(){ try{ beatSequencer = MidiSystem.getSequencer(); beatSequencer.open(); beatSequencer.setTempoInBPM(120); // Create a new beatSequence and set the timing to 4 pulses per quarter note beatSequence = new Sequence (Sequence.PPQ, 4); // Create a new Track to hold the midi data beatTrack = beatSequence.createTrack(); } catch (Exception e){ e.printStackTrace(); } } // @reference: Head First Java, Second Edition, Sierra K & Bates B, 2005. // Method to build our track based on the data held from checkbox clicks public void buildTrackAndStart(){ int [] trackList = null; /* Delete existing track data and create a new empty track (Do this so everytime play button gets pressed the existing track data will be wiped and a new track created to contain the up to date data)*/ beatSequence.deleteTrack(beatTrack); beatTrack = beatSequence.createTrack(); // Outer loop to check the state of each of the rows (i.e. Bass, Congo etc.). for (int i = 0; i < 16; i++){ /* This array is going to hold the state of the 16 checkboxes in each row. Should the instrument play at each position in the row? If the checkbox is selected (see loop below) this array will hold the midi instrument (number) to be played. If an instrument is to be played 16 times in succession, this array will hold something like [35, 35, 35, 35, 35, 35, 35, 35, 35, 35, 35, 35, 35, 35, 35, 35] (depends on instrument midi number) */ trackList = new int [16]; /* Set the instrument (MIDI key) for each row based on the instruments [] data above. Loop 1 this will be 35. Loop 2 will be 42 etc. */ int key = instruments [i]; /* // Inner loop to populate each row with data on the state of each checkbox in that row i.e. selected/on (true) or not selected/off (false)*/ for (int j = 0; j < 16; j++){ /* // Local variable to collect data on the state of each checkbox in the row. Gets the data from the checkBoxState ArrayList. That ArrayList is holding the state of each of the 256 checkboxes. Outer and inner loop above creates 256 checkboxes (loops 16 x 16) called jcb. (j + (16 * i) => Outer loop(i) 0, Inner Loop(j): 0, 1, 2.....16; Outer loop(i) 1, Inner Loop(j): 16, 17, 18...... */ JCheckBox jcb = (JCheckBox)checkBoxState.get(j + (16 * i)); if (jcb.isSelected()){ // If the checkbox is selected, add the instrument to be played data to the trackList array. trackList[j] = key; } else{ trackList[j] = 0; } } /* // For each loop of the outer loop, add the trackList array data to a track by calling the makeTracks method below and sending it an array of data (i.e. the instrument number if to be played or a 0 if not. */ makeTracks(trackList); /* // I think the following command adds a Midi Control Change (176) to turn off all sound after tick 16. // Does this by calling the makeEvent method. Looks like it does it on channel 1. */ beatTrack.add(makeEvent(176, 1, 127, 0, 16)); } /* This line adds an event to beat 16 (it goes 0-15) of each row. Otherwise if there were none, the BeatBox might not go the full 16 beats before it starts over. 192 is change instrument. Think it reads: change instrument on channel 9 to instrument 1 at tick 15. Nothing actually happens but the event needs to be there for the reason above. */ beatTrack.add(makeEvent(192, 9, 1, 0, 15)); // Try Catch to add our sequence to the sequencer. Throw an exception if fails. try{ beatSequencer.setSequence(beatSequence); beatSequencer.setLoopCount(beatSequencer.LOOP_CONTINUOUSLY); beatSequencer.start(); beatSequencer.setTempoInBPM(120); } catch (Exception e){ e.printStackTrace(); } } // @reference: Head First Java, Second Edition, Sierra K & Bates B, 2005. /* // This is the method to add midi data to the tracks. It adds Midi events at places in the track. For the method to be called it must be sent an array of ints. We then name this array received "list".*/ public void makeTracks (int [] list){ // Loop to take the instrument number and create a MidiEvent and add the MidiEvent to the track. for (int i = 0; i < 16; i++){ // Take the data in the int [] ("list"), sent when the method called, and store them in an int [] "key". int key = list [i]; // If the data in an array element is 0, do not add a Midi event. Otherwise do. if (key != 0){ // Add a MidiEvent to our track. // Create the MidiEvent by calling the make Event method and sending it the data noted. beatTrack.add(makeEvent(144, 9, key, 100, i)); beatTrack.add(makeEvent(128, 9, key, 100, i+1)); } } } /* @reference: Head First Java, Second Edition, Sierra K & Bates B, 2005. // Method to create MidiEvents that will get added to the track. Note the return type is MidiEvent rather than void.*/ public MidiEvent makeEvent (int command, int channel, int one, int two, int tick){ MidiEvent event = null; try{ ShortMessage a = new ShortMessage(); a.setMessage (command, channel, one, two); event = new MidiEvent (a, tick); } catch (Exception e){ e.printStackTrace(); } return event; } // @author Alan Dunne, x11105160 public void start(){ buildTrackAndStart(); } // @author Alan Dunne, x11105160 public void stop(){ beatSequencer.stop(); } // @author Alan Dunne, x11105160 public void upTempo(){ float tempoNum = beatSequencer.getTempoFactor(); beatSequencer.setTempoFactor((float)(tempoNum * 1.035)); } // @author Alan Dunne, x11105160 public void downTempo(){ float tempoNum = beatSequencer.getTempoFactor(); beatSequencer.setTempoFactor ((float)(tempoNum * 0.965)); } // @reference: Head First Java, Second Edition, Sierra K & Bates B, 2005. // as modified by @author Alan Dunne, x11105160 public void saveBeatBox(File file){ boolean [] savedCheckBoxState = new boolean [256]; for (int i = 0; i < 256; i++){ JCheckBox state = (JCheckBox) checkBoxState.get(i); if (state.isSelected()){ savedCheckBoxState [i] = true; } } try{ FileOutputStream fileOut = new FileOutputStream (file); ObjectOutputStream objectOutStream = new ObjectOutputStream (fileOut); objectOutStream.writeObject(savedCheckBoxState); } catch (Exception ex){ System.out.println("Sorry but we could not save your song."); ex.printStackTrace(); } } /*/ @reference: Head First Java, Second Edition, Sierra K & Bates B, 2005. as modified by @author Alan Dunne, x11105160 */ public void loadBeatBox (File file){ boolean [] loadCheckBoxState = null; try{ FileInputStream fileIn = new FileInputStream (file); ObjectInputStream objectInStream = new ObjectInputStream (fileIn); loadCheckBoxState = (boolean []) objectInStream.readObject(); } catch (Exception ex){ System.out.println("Sorry but we could not load your song."); ex.printStackTrace(); } for (int i = 0; i < 256; i++){ JCheckBox check = (JCheckBox) checkBoxState.get(i); if (loadCheckBoxState[i]){ check.setSelected(true); } else{ check.setSelected(false); } } beatSequencer.stop(); buildTrackAndStart(); } // @author Alan Dunne, x11105160 public void clearPattern(){ for (int i = 0; i < 256; i++){ JCheckBox check = (JCheckBox) checkBoxState.get(i); check.setSelected(false); } beatSequencer.stop(); buildTrackAndStart(); beatSequencer.stop(); } }

Great that's the Line 6 casting answered. Thanks William. What you mean about Generics <>? Around my queries?

Hi all,

I hope I've put this in the correct forum.

I've completed the Head First Java Beat Box and everything worked fine. I then went on to the saving and restoring part and got that working (note I added a JFileChooser to my code). The problem I'm having is getting my head around the file restore part of the code as follows (note I made some variable/method name changes etc to the Head First code):-

public void loadBeatBox (File file){ boolean [] loadCheckBoxState = null; try{ FileInputStream fileIn = new FileInputStream (file); ObjectInputStream objectInStream = new ObjectInputStream (fileIn); loadCheckBoxState = (boolean []) objectInStream.readObject(); } catch (Exception ex){ System.out.println("Sorry but we could not load your song."); ex.printStackTrace(); } for (int i = 0; i < 256; i++){ JCheckBox check = (JCheckBox) checkBoxState.get(i); if (loadCheckBoxState[i]){ check.setSelected(true); } else{ check.setSelected(false); } } beatSequencer.stop(); buildTrackAndStart(); }

From what I understand so far, the code above does the following:
Line 2 - Declare a boolean array called "loadCheckBoxState" and set it to null.
Lines 4/5 - Create a new object input stream to read from the saved file that gets passed to it.
Line 6 - Create the loadCheckBoxState boolean array. Then fill it with the contents of the objectInput stream, casted as a boolean array (boolean []). Q1. I'm not sure why it has to be casted as the file was saved as a boolean array?
Line 13 - Create a loop to iterate 256 times.

Now here's where my major problem is.
Line 14 - Declare a JCheckBox check and make it equal to the state of the actual checkbox in the class (note checkBoxState is the checkBox that was loaded into the ArrayList and the panel in the code not re-produced above) at the loop position. Q2. It's this line that's getting me. Why do we need to cast "(JCheckBox)"??? And how does this code actually change the checkBoxState checboxes in the code not re-produced (which are used to create the MIDI and build the track)??? To me this line reads make the JCheckBox check = the state of the JCheckBox checkBoxState
Lines 15 - Lines 19 - Iterate through the saved file and if the loaded checkbox is true/false, make the JCheckBox check true/false. My questions on this line will be answered (I think) if someone can answer my questions on Line 14.

Any help would be much appreciated. I hope I'm being clear in what I'm asking.

I can reproduce the full class if it would make it easier.

Thanks,

Al.

Hi Paul,

I'm fairly new to this so I was getting confused about where I should call the stop method. I had it in a few places but it wasn't working. I really don't understand about Clips etc yet.

I got the solution on another website yesterday afternoon. It was to put the following code before the try-catch in the playSound method.

if (clip != null && clip.isRunning()) { clip.stop(); }

Thanks for your reply though.

Al.

Ok thanks Greg.

Hi all,

I'm fairly new to this so I hope I've posted this to the correct place.

I'm completing a project where a user gets to press a few buttons and they will see a waveform change and hear the amplitude of a sound increase or decrease. To get the sounds to play I'm using javax.sound.sampled.*

My code is as follows (the buttons the user presses are in a seperate GUI built class):-

import java.awt.Color; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.Image; import java.awt.Toolkit; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.io.*; import javax.swing.ImageIcon; import javax.swing.JPanel; import javax.swing.Timer; import javax.sound.sampled.*; public class WaveAnimation extends JPanel implements ActionListener{ private Timer animator; private ImageIcon [] imageArray; private ImageIcon [] activeImageArray; private int delay = 300, totalFrames = 18, currentFrame = 0, activeImage1 = 0, activeImage2 = 1; private int activeSound = 0; File [] soundFile ; AudioInputStream audio; Clip clip; public WaveAnimation(){ imageArray = new ImageIcon[totalFrames]; for (int i = 0; i < imageArray.length; i++){ imageArray[i] = new ImageIcon(this.getClass().getResource("Wave"+i+".png")); } activeImageArray = new ImageIcon[2]; activeImageArray[0] = imageArray[activeImage1]; activeImageArray[1] = imageArray[activeImage2]; animator = new Timer(delay, this); animator.start(); soundFile = new File [9]; for (int i = 0; i < 9; i++){ soundFile [i] = new File (i+"db.wav"); } } public void paintComponent(Graphics g){ super.paintComponent(g); if (currentFrame >= activeImageArray.length){ currentFrame = 0; } activeImageArray[currentFrame].paintIcon(this, g, 0, 0); currentFrame++; } public void actionPerformed(ActionEvent e){ repaint(); } public void increaseAmplitude(){ if (activeImage1 == (totalFrames - 2)){ activeImage1 = activeImage1; activeImage2 = activeImage2; } else { activeImage1 = activeImage1 + 2; activeImage2 = activeImage2 + 2; activeImageArray[0] = imageArray[activeImage1]; activeImageArray[1] = imageArray[activeImage2]; // stopSound(); activeSound++; playSound(); System.out.println("The activeSound is"+activeSound); } } public void decreaseAmplitude(){ if (activeImage1 == 0){ activeImage1 = activeImage1; activeImage2 = activeImage2; } else { activeImage1 = activeImage1 - 2; activeImage2 = activeImage2 - 2; activeImageArray[0] = imageArray[activeImage1]; activeImageArray[1] = imageArray[activeImage2]; // stopSound(); activeSound--; playSound(); System.out.println("The activeSound is"+activeSound); } } public void playSound(){ try { audio = AudioSystem.getAudioInputStream(soundFile[activeSound]); clip = AudioSystem.getClip(); clip.open(audio); clip.start(); clip.loop(Clip.LOOP_CONTINUOUSLY); } catch (IOException ex){ System.out.println("Sorry but there has been a problem reading your file."); ex.printStackTrace(); } catch (UnsupportedAudioFileException ex1){ System.out.println("Sorry but the audio file format you are using is not supported."); ex1.printStackTrace(); } catch (LineUnavailableException ex2){ System.out.println("Sorry but there are audio line problems."); ex2.printStackTrace(); } } }

The actual sounds are 10 seconds long so I want them to loop continuously until the user either increases or decreases the amplitude.

All my code is working fine. However, the problem I'm having is that everytime the user clicks the increase amplitude button and calls the playSound method, a new audio line gets opened and the sounds play at the same time.

Is there a way I can close all existing audio lines before a new one is opened? I've been looking for a couple of hours now but am getting more and more frustrated/confused.

Any help would be much appreciated.

Al.