|
|
Welcome to the Java Forums.
You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community, you will:
- have access to post topics
- communicate privately with other members (PM)
- not see advertisements between posts
- have the possibility to earn one of our surprises if you are an active member
- access many other special features that will be introduced later.
Registration is fast, simple and absolutely free so please, join our community today!
If you have any problems with the registration process or your account login, please contact us.
|
|

09-02-2008, 02:25 AM
|
|
Senior Member
|
|
Join Date: Dec 2007
Location: Spain
Posts: 342
|
|
|
Once again: waiting in a thread loop.
(Or how to get into one and, most importantly, how to get out of a one.)
I haven’t seen any better alternative to my previous loop constructions! Maybe because loops form the very hearth of computers and there functioning. Almost everything, concerning a computer, is loop cycle; a program is one the processor cycle is one, events are loops… the poor thing has actually noting better to do than spinning its loops (I know, now that nick is reading carefully- – he thinks that I am joking, but I am not, this looping bossiness is very serious to me… so he will “surprise” me with another mysterious code which should put my thinking into a loop (because he is actually the joker of our forum).
So here is another example, but this time, norm’s question “when you get out of it, what than??? (note, the question marks… norm is really curious here… or maybe upset?) should be answered better this time:
This new loop waits for the sound tracks to start and is note at the GUI class where buttons etc. are pushed. It sits at the class where all the sounblocks are. The loop happens, again, inside a thread (I start to like threads), so here it is:
class Waitloop extends Thread {
public Waitloop() { // the thread counter
cnt++;
System.out.println("count wait thread " + cnt); // to see what it is looping
}
public void run() {
cont.setstartFlag(false);
do {
} while (!cont.getstartFlag());
cont.setstartFlag(false);
System.out.println("exit thread " + cnt);
mainSoundblock(1);
}
}
The loop will keep the thread busy spinning until the method call of the GUI class turns true. Than the flag gets reset and the important mainSoundblock(1); method starts WITHIN THE THREAD.
Consider the working of this method similar to a pin-ball machine. The little ball starts at the very top but eventually will reach the bottom. The if’s, when turn false, will push the ball hard (the esc key was pressed). Each soundblock takes from 20 sec. to several minutes (depending on midi pedals, remember). When reaching the end the thread is over and the cycle/ thread repeats by pushing the start button.
private void mainSoundblock(int trck) {
cont.ed.resetFbo();
if (trck==1 && !cont.getescFlag()) {
Soundblock1();
cont.settrackNumb(trck);
trck=2;
}
else
if (trck==2 && !cont.getescFlag()) {
Soundblock2();
cont.settrackNumb(trck);
trck=3;
}
else
if (trck==3 && !cont.getescFlag()) {
Soundblock3();
cont.settrackNumb(trck);
trck=4;
}
else
if (trck==4 && !cont.getescFlag()) {
Soundblock4();
cont.settrackNumb(trck);
trck=5;
}
else
if (trck==5 && !cont.getescFlag()) {
Soundblock5();
cont.settrackNumb(trck);
trck=6;
}
else
if (trck==6) {
Soundblock6();
exit();
cont.settrackNumb(trck);
trck=7;
}
else
if (trck==7 && !cont.getescFlag()) {
Soundblock7();
cont.settrackNumb(trck);
trck=8;
}
else
if (trck==8) {
Soundblock8();
cont.settrackNumb(trck);
trck=9;
}
else
if (trck==9 && !cont.getescFlag()) {
Soundblock9();
exit();
cont.settrackNumb(trck);
trck=10;
}
else
if (trck==10 && !cont.getescFlag()) {
Soundblock10();
cont.settrackNumb(trck);
trck=11;
}
else
if (trck==11 && !cont.getescFlag()) {
Soundblock11();
cont.settrackNumb(trck);
trck=12;
}
else
if (trck==12 && !cont.getescFlag()) {
Soundblock12();
cont.settrackNumb(trck);
trck=1;
}
System.out.println(" final of sound block " );
cont.setescFlag(false);
cont.ed.closeFbo1();
cont.stopclk();
}
|
|

09-02-2008, 02:36 AM
|
|
Senior Member
|
|
Join Date: Dec 2007
Location: Spain
Posts: 342
|
|
By the way PK, when coming out of the loop and NOT coming out of the thread, all the buttons, besides the escape, are turned off (xxx.setEnabled(false)  so that no other thread, besides the midipedal and escape, can disturb the pin ball.
|
|

09-02-2008, 02:37 AM
|
|
Senior Member
|
|
Join Date: Dec 2007
Location: Spain
Posts: 342
|
|
|
this funny head appeared by itself?
|
|

09-02-2008, 03:29 AM
|
|
Senior Member
|
|
Join Date: Aug 2008
Posts: 179
|
|
nice, and yes, it did you probably tried
where the ; ) turns into that smiley 
__________________
check out To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts. , 100% made by me. To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
|
|

09-02-2008, 05:19 AM
|
 |
Senior Member
|
|
Join Date: Jun 2008
Location: Heredia, Costa Rica
Posts: 2,223
|
|
|
The question still is: why can't you start a thread that calls mainSoundblock(1); when/where the cont.getStartFlag() flag is set?
Why spin in a loop waiting for an event before calling a method, when the event itself could start a thread to call the method?
The setting and testing and reseting of the flag is a great waste of time and code.
|
|

09-02-2008, 11:16 AM
|
|
Senior Member
|
|
Join Date: Dec 2007
Location: Spain
Posts: 342
|
|
|
Yes norm, we might get to the center of this problem (maybe a lack of java imagination of mine). Java does not support multiple inheritance, right. I red some stuff about that, and the point I got out of that all, is that they do not want to turn java into the spaggetti-code mess of C++. I started out with java and do not know any better, good! (I choose for java, because I do not feel any sympathy for the micro-soft (Chicago) software-boys – if you want to know more about that, read Naomi Klein’s latest, The Shock Doctrine (yes, nick I believe we should show our code-biting-juniors about the many hidden background stories of this world).
Okay let’s follow the thread, when the Main class on top of the other classes creates an instance of the second Controler class, that has all the GUI stuff, THERE IS A ONE WAY DIRECTION OF INFORMATION, right. When the instance of the GUI-class, called “cont”, created at the Main-class (where all the soundblocks are, remember) wants to get data from the GUI-class it gets it by cont.whatever(); If I create a thread at one of the event-notifying methods (of the GUI-class) I WOULD BE GOING INTO THE OPPOSITE DIRECTION. Nick, got that problem (I should say he is smart), but his code is any good….. is it? (do { } while (codeofNick( true/false); Nick you should NOT crunch first-years students of English with Shakespeare!
|
|

09-02-2008, 11:46 AM
|
|
Senior Member
|
|
Join Date: Dec 2007
Location: Spain
Posts: 342
|
|
|
In case you haven't followed other similar threaeds
the code and text of nick:
class A {
B b;
A(B bee){
b = bee;
Class A now can do and call methods of a class B on the name "b" thus:
b.doSomething(data);
In the class that has the button pushing stuff, we have a remarkably simple adjunct but that requires you grasp this first,.... then we still have to drive the controller class in a non-blocked manner using the clock I described in the don't ask me to which you refer.
|
|

09-02-2008, 04:27 PM
|
 |
Senior Member
|
|
Join Date: Jun 2008
Location: Heredia, Costa Rica
Posts: 2,223
|
|
Where is the instance of the Waitloop class created?
Another idea. Change the run method in Waitloop as follows:
public void run() {
cont.returnWhenICanExecute(this);
mainSoundblock(1);
}
The returnWhenICanExecute method would loop/wait until the event occured when you want the mainSoundblock method to be called. This would simplify the design by not requiring the run method to know about setting and clearing flags in the cont class.
Last edited by Norm : 09-02-2008 at 05:52 PM.
|
|

09-03-2008, 06:49 PM
|
|
Senior Member
|
|
Join Date: Dec 2007
Location: Spain
Posts: 342
|
|
Mozart did not like the flute and when he was asked what he considers worse, he answered two flutes!
Finale I have the the program working. I have tested the application many times and everything works just fine. I have to take care of some esthetical things.... and done.
Probably the underlaying mistake of the program is that I did not put the GUI stuff into the top class. I have two waitloops taking care of the GUI management, and one in a new created thread. (PK, I did synchronize some method concerning your remark)
private void waitloop() {
wl = new Waitloop();
wl.start();
cont.setstartFlag(false);
cont.selectonoff(true);
start=false;
do { } while (!start); // wait for start button
int trc = cont.gettrackNumb(); // read out the track number
mainSoundblock(trc);
}
class Waitloop extends Thread {
public Waitloop() {
cnt++; // the thread counter
System.out.println("count wait thread " + cnt); // to see what it is looping
}
public void run() {
cont.setstartFlag(false);
do {
} while (!cont.getstartFlag()); // read the start button
start=true;
System.out.println("exit thread " + cnt);
}
}
private void mainSoundblock(int trck) {
cont.ed.resetFbo();
cont.setescFlag(false);
trig=false; exit=false;
if (trck==1 && !cont.getescFlag()) {
Soundblock1();
cont.settrackNumb(trck);
trck=2;
}
if (trck==2 && !cont.getescFlag()) {
Soundblock2();
cont.settrackNumb(trck);
trck=3;
}
if (trck==3 && !cont.getescFlag()) {
Soundblock3();
cont.settrackNumb(trck);
trck=4;
}
if (trck==4 && !cont.getescFlag()) {
Soundblock4();
cont.settrackNumb(trck);
trck=5;
}
....... etc until 12
System.out.println(" end of sound block " );
cont.setescFlag(false);
// cont.ed.closeFbo1();
cont.stopclk();
cont.ed.resetFbo();
waitloop();
}
Sure next programming project I should design differently and I will try to get rid of those un-elegant cpu consuming loops.
Two more questions
1) when appending text into a JTextArea, how could I keep the new text on sight at the screen (the new appended text scrolls down and disappears)?
2) Before going out of the application, at the very last moment, I would like to clean up some things (clossing drivers etc.). I am using the standard
window.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
to exit.
|
|

09-03-2008, 07:37 PM
|
 |
Senior Member
|
|
Join Date: Jun 2008
Location: Heredia, Costa Rica
Posts: 2,223
|
|
WOW. You have 2 dead,useless loops!
Before going out of the application
Don't use EXIT_ON_CLOSE.
Use a Window Listener to catch window closing and put a call to your cleanup code there.
|
|

09-03-2008, 07:44 PM
|
|
Senior Member
|
|
Join Date: Dec 2007
Location: Spain
Posts: 342
|
|
|
ok.
.......... than I am going to need another loop?
|
|

09-03-2008, 08:05 PM
|
|
Senior Member
|
|
Join Date: Dec 2007
Location: Spain
Posts: 342
|
|
|
There is something I am not getting here!
Class A //sound blocks data
B b = new B();
b.whateverMethod(); //of class B
Cass B extends JPanel //GUI listeners buttons etc.
There happens an event in class B (at any time!!!) how this can be noted in A???
e.g. listener sets boolean midipedal to true
public boolean getMidiped() { // at class B
return midipedal;
}
At class A I could ask for b.getMidiped() and it will return the correct true or false of the var. BUT I DO NOT KNOW WHEN THAT WILL HAPPEN FROM INSIDE THE CODE OF CLASS A SO THAT IS WHY I NEED A LOOP TO WAIT THIS TO HAPPEN......... OR NOT???
|
|

09-03-2008, 08:30 PM
|
|
Senior Member
|
|
Join Date: Dec 2007
Location: Spain
Posts: 342
|
|
|
do {
I am trapped in a loop...... who can help me out
} while(who?);
|
|

09-03-2008, 08:42 PM
|
 |
Senior Member
|
|
Join Date: Jun 2008
Location: Southwest
Posts: 789
|
|
|
this funny head appeared by itself?
Originally Posted by willemjav
the many hidden background stories of ..
I was busy yesterday, finally got a script to run late at night so I did not have time to crawl your code. You have, however you got there, arrived at the central issue on threading - do not know when something will happen - and there lay the keys to your code design. Spin loops are generally considered to waste processor power, thus whether sleep and yield work correctly become central design issues. Unfortunately, robust design of para-realtime scheduling is beyond contemporary practice in Java.
Sun Java Real-Time System - Mediacasts
Efforts are in place to achieve a more robust wording that scales to mainframe.
Dr. Doug Locke may have some advanced observations if you wish to study the matter. Bascially, use synchronized, do not try to do it with bumping priorities. Choose one class, ala hardwired's recent post in the other thread, to be your main class - which should somehow account for button pushing in the GUI - my design has a clock in a hard spin, we do if ( boolean ) in that class ( instance ? ) and manipulate that boolean from the controller class ... we can think of the clock as a Propogator, but you can call me Alligator. ( ! )
__________________
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts. .
Cybercartography: A new theoretical construct proposed by D.R. Fraser Taylor
|
|

09-03-2008, 09:55 PM
|
 |
Senior Member
|
|
Join Date: Jun 2008
Location: Heredia, Costa Rica
Posts: 2,223
|
|
|
Replacement of loop with wait and notify
I took your posted code, made it into something that would execute and then modified it to use wait and notify:
First is your code with some dummy stuff:
// willemjav looping problem
public class WaitLoops {
boolean start;
Cont cont;
Waitloop wl;
//-----------------------------------------------------------
// Wait until start set
private void waitloop() {
wl = new Waitloop();
wl.start();
cont.setstartFlag(false);
// cont.selectonoff(true);
start=false;
System.out.println(">>waitloop - entering loop");
do { } while (!start); // wait for start button
System.out.println(">>waitloop - exited loop");
int trc = cont.gettrackNumb(); // read out the track number
mainSoundblock(trc);
} // end waitloop()
int cnt;
//-------------------------------------------------------------------------
// Wait until StartFlag set
class Waitloop extends Thread {
public Waitloop() {
cnt++; // the thread counter
System.out.println("count wait thread " + cnt); // to see what it is looping
}
public void run() {
cont.setstartFlag(false);
do { } while (!cont.getstartFlag()); // read the start button
start=true; // release waitloop looping
System.out.println("exited thread " + cnt);
}
}
class Cont {
boolean flag;
boolean esc;
int tn;
boolean getstartFlag(){return flag;}
void setstartFlag(boolean f){
flag = f;
System.out.println("set start flag " + flag);
}
int gettrackNumb() {return tn;}
void settrackNumb(int trck) {tn = trck;}
boolean getescFlag() {return esc;}
void setescFlag(boolean f) {esc = f;}
}
private void mainSoundblock(int trck) {
// cont.ed.resetFbo();
cont.setescFlag(false);
// trig=false;
// exit=false;
if (trck==1 && !cont.getescFlag()) {
Soundblock1();
cont.settrackNumb(trck);
trck=2;
}
if (trck==2 && !cont.getescFlag()) {
Soundblock2();
cont.settrackNumb(trck);
trck=3;
}
if (trck==3 && !cont.getescFlag()) {
Soundblock3();
cont.settrackNumb(trck);
trck=4;
}
if (trck==4 && !cont.getescFlag()) {
Soundblock4();
cont.settrackNumb(trck);
trck=5;
}
// ....... etc until 12
System.out.println(" end of sound block " );
cont.setescFlag(false);
// cont.ed.closeFbo1();
// cont.stopclk();
// cont.ed.resetFbo();
waitloop(); // NCR - RECURSIVE CALL???
} // end mainSoundBlock
void Soundblock1(){}
void Soundblock2(){}
void Soundblock3(){}
void Soundblock4(){}
// Constructor --------------------------------
public WaitLoops() {
cont = new Cont();
// Start a thread to set flag in 2 seconds
Thread t = new Thread(new Runnable() {
public void run() {
for(int i=0; i < 5; i++) {
try{Thread.sleep(2000);}catch(Exception x){}
cont.setstartFlag(true); // release Waitloop thread looping
} // end for(i)
System.exit(0); // EXIT - END OF TEST
}
});
t.start();
waitloop();
}
//--------------------------------------------------------------------
// Test the above
public static void main(String[] args) {
new WaitLoops();
}
} // end class
/*
Running: "C:\Program Files\Java\j2re1.4.2_08\bin\java.exe" -cp D:\JavaDevelopment\Testing\JavaForum\;D:\JavaDevelopment;. WaitLoops
count wait thread 1
set start flag false
>>waitloop - entering loop
set start flag false
set start flag true <<<<<<< After 2 sec sleep
exited thread 1
>>waitloop - exited loop
end of sound block
count wait thread 2
set start flag false
>>waitloop - entering loop
set start flag false
>>>>>>>>>>> HERE I C+A+D and ended task
0 error(s)
*/
Then modified to use wait / notify
// willemjav looping problem - Changed to use wait() and notifyAll()
public class WaitLoops2 {
Cont cont;
int cnt;
//-----------------------------------------------------------
// Wait until "user" presses start button (uses getstartFlag)
private void waitloop() {
while(true) { // do loop here vs a recursive call from mainSoundblock
cnt++;
Object mon = cont.setstartFlag(false); // be sure flag is off / get monitor
// cont.selectonoff(true);
System.out.println(">>waitloop - entering loop " + cnt);
while(!cont.getstartFlag()) {
synchronized(mon) {
try{mon.wait();}catch(Exception x){} // wait until button pressed
}
}
System.out.println(">>waitloop - exited loop " + cnt);
int trc = cont.gettrackNumb(); // read out the track number
mainSoundblock(trc);
}
} // end waitloop()
//----------------------------------------------------
// Dummy class for testing
class Cont {
boolean flag;
boolean esc;
int tn;
Object mon = new Object();
boolean getstartFlag(){
return flag;
}
Object setstartFlag(boolean f){
flag = f;
System.out.println("set start flag " + flag);
if(flag) { // when flag is set, release those waiting
synchronized(mon) {
mon.notifyAll(); // wakeup waiting thread
}
}
return mon; // return monitor so caller can wait() on it
}
int gettrackNumb() {return tn;}
void settrackNumb(int trck) {tn = trck;}
boolean getescFlag() {return esc;}
void setescFlag(boolean f) {esc = f;}
}
private void mainSoundblock(int trck) {
// cont.ed.resetFbo();
cont.setescFlag(false);
// trig=false;
// exit=false;
if (trck==1 && !cont.getescFlag()) {
Soundblock1();
cont.settrackNumb(trck);
trck=2;
}
if (trck==2 && !cont.getescFlag()) {
Soundblock2();
cont.settrackNumb(trck);
trck=3;
}
if (trck==3 && !cont.getescFlag()) {
Soundblock3();
cont.settrackNumb(trck);
trck=4;
}
if (trck==4 && !cont.getescFlag()) {
Soundblock4();
cont.settrackNumb(trck);
trck=5;
}
// ....... etc until 12
System.out.println(" end of sound block " );
cont.setescFlag(false);
// cont.ed.closeFbo1();
// cont.stopclk();
// cont.ed.resetFbo();
if(cnt == 4) { // debug to show recursive calls - NONE with this code
try{throw new Exception("Show Call Stack");}catch(Exception x){x.printStackTrace();}
/*
java.lang.Exception: Show Call Stack
at WaitLoops2.mainSoundblock(WaitLoops2.java:97)
at WaitLoops2.waitloop(WaitLoops2.java:23)
at WaitLoops2.<init>(WaitLoops2.java:123)
at WaitLoops2.main(WaitLoops2.java:129)
*/
}
} // end mainSoundBlock
// Dummy methods
void Soundblock1(){}
void Soundblock2(){}
void Soundblock3(){}
void Soundblock4(){}
// ...
// Constructor --------------------------------
public WaitLoops2() {
cont = new Cont();
// Start a thread to set flag in 2 seconds
// This is to simulate user pressing a button
Thread t = new Thread(new Runnable() {
public void run() {
for(int i=0; i < 5; i++) {
try{Thread.sleep(2000);}catch(Exception x){}
cont.setstartFlag(true); // press button
} // end for(i)
System.exit(0); // EXIT - END OF TEST
}
});
t.start();
waitloop(); // Start the program process
} // end Constructor
//--------------------------------------------------------------------
// Test the above
public static void main(String[] args) {
new WaitLoops2();
}
} // end class
/*
Running: "C:\Program Files\Java\j2re1.4.2_08\bin\java.exe" -cp D:\JavaDevelopment\Testing\JavaForum\;D:\JavaDevelopment;. WaitLoops2
set start flag false
>>waitloop - entering loop 1
set start flag true
>>waitloop - exited loop 1
end of sound block
set start flag false
>>waitloop - entering loop 2
set start flag true
>>waitloop - exited loop 2
end of sound block
set start flag false
>>waitloop - entering loop 3
set start flag true
>>waitloop - exited loop 3
end of sound block
set start flag false
>>waitloop - entering loop 4
set start flag true
>>waitloop - exited loop 4
end of sound block
java.lang.Exception: Show Call Stack
at WaitLoops2.mainSoundblock(WaitLoops2.java:97)
at WaitLoops2.waitloop(WaitLoops2.java:23)
at WaitLoops2.<init>(WaitLoops2.java:123)
at WaitLoops2.main(WaitLoops2.java:129)
set start flag false
>>waitloop - entering loop 5
set start flag true
>>waitloop - exited loop 5
end of sound block
set start flag false
>>waitloop - entering loop 6
0 error(s)
*/
|
|

09-03-2008, 10:17 PM
|
|
Senior Member
|
|
Join Date: Dec 2007
Location: Spain
Posts: 342
|
|
|
Thanks norm, I'll need some time to study all that
|
|

09-04-2008, 02:30 AM
|
 |
Senior Member
|
|
Join Date: Jun 2008
Location: Heredia, Costa Rica
Posts: 2,223
|
|
Your design seems backwards. Normally the GUI class is instantied first and starts the worker class (to do any init it needs) and then exits to let the GUI engine wait for user input. When the user does something, a listener is called which then calls(via a new Thread) the worker class to do whatever needs to be done.
Here's a new version of your program configured to work that way:
// willemjav looping problem - Add GUI to call mainSoundblock at button press
import javax.swing.*;
import java.awt.event.*;
import java.awt.*;
public class WaitLoops3 extends JFrame implements ActionListener {
JButton doItBtn = new JButton("Do it");
Cont cont;
int cnt;
//----------------------------------------------------
// Dummy class for testing
class Cont {
boolean esc;
int tn = 1;
int gettrackNumb() {return tn;}
void settrackNumb(int trck) {tn = trck;}
boolean getescFlag() {return esc;}
void setescFlag(boolean f) {esc = f;}
} // end class Cont
public void actionPerformed(ActionEvent ae) {
Object obj = ae.getSource();
if(obj == doItBtn) {
// Start task on own thread
Thread t = new Thread(new Runnable() {
public void run() {
mainSoundblock(cont.gettrackNumb());
}
});
t.start();
}else {
System.out.println("unknown ae" + ae);
}
} // end actionPerformed
//------------------------------------------------------
private void mainSoundblock(int trck) {
// cont.ed.resetFbo();
cont.setescFlag(false);
// trig=false;
// exit=false;
if (trck==1 && !cont.getescFlag()) {
Soundblock1();
cont.settrackNumb(trck);
trck=2;
}
if (trck==2 && !cont.getescFlag()) {
Soundblock2();
cont.settrackNumb(trck);
trck=3;
}
if (trck==3 && !cont.getescFlag()) {
Soundblock3();
cont.settrackNumb(trck);
trck=4;
}
if (trck==4 && !cont.getescFlag()) {
Soundblock4();
cont.settrackNumb(trck);
trck=5;
}
// ....... etc until 12
System.out.println(" end of sound block @ " + System.currentTimeMillis() );
cont.setescFlag(false);
// cont.ed.closeFbo1();
// cont.stopclk();
// cont.ed.resetFbo();
} // end mainSoundBlock
// Dummy methods
void Soundblock1(){System.out.println("Soundblock1");}
void Soundblock2(){System.out.println("Soundblock2");}
void Soundblock3(){System.out.println("Soundblock3");}
void Soundblock4(){System.out.println("Soundblock4");}
// ...
// Constructor --------------------------------
// Build the GUI and wait for user's input
public WaitLoops3() {
super("Do it when button pressed");
cont = new Cont();
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Container pane = getContentPane();
JPanel panel = new JPanel();
doItBtn.addActionListener(this);
panel.add(doItBtn);
pane.add(panel);
pack();
setLocation(300, 200); // move out of corner
setVisible(true);
} // end Constructor
//--------------------------------------------------------------------
// Test the above
public static void main(String[] args) {
new WaitLoops3();
}
} // end class
|
|

09-04-2008, 03:24 AM
|
 |
Senior Member
|
|
Join Date: Jun 2008
Location: Southwest
Posts: 789
|
|
|
do{}while(); is not wait() / notifiy()
Originally Posted by willemjav
(Or how to get into one and, most importantly, how to get out of a one.)
Really simple:
class Music implements List of Some Kind{
List notes;
Position position;
Boolean playing;
Music(){
// ....? maybe set music type or something
}
public void nextNote()
{
++position;
}
}
//
//
class Controller extends GUI / AWT / Graphical {
Button goButton;
Button stopButton;
Boolean ExitProgram; // Actually, you do not need this
//
MasterClock mc;
//
Controller(MasterClock mc){
this.mc = mc;
}
public void ButtonHandler(ButtonPush bp)
{
if(bp == goButtonPush)
{
mc.startPlay();
}
if(bp == stopButtonPush)
{
mc.stopPlay();
}
}
public void stopPlay()
{
mc.exit();
}
}
class MasterClock implements Runnable
{
//
private Ticker;//
private List waits;
//
Boolean running = new Boolean(true);
//
public void run
{
while(running.BooleanValue())
{
//
if(++Ticker > NextTimeToMoveOnList)
{
Music.nextNote();
}
// Looks funny, but is closer to correct practice.
sleep(0);
}
}
public void startPlay()
{
running = new Boolean(true);
}
public void stopPlay()
{
running = new Boolean(false);
}
public void exit()// Not use yet....
}
Originally Posted by willemjav
I haven’t seen any better alternative to my previous loop constructions!
You have now, though this has considerable detail left out.
Originally Posted by willemjav
Maybe because loops form the very hearth of computers and there functioning.
Basically, this is close to technically correct.
Originally Posted by willemjav
Almost everything, concerning a computer, is loop cycle.
Yes.
Originally Posted by willemjav
 | | |