Multithreading, need help figuring out how to reach the parent 1

Karl Blessing · Mar 23, 2000

I have the following example 
 
import java.lang.Thread; 
 
public class TCon 
{ 
int MyNum; 
public static void main (String[] args) 
{ 
Thread F = new RThread("T1", 250); 
Thread S = new RThread("T2", 750); 
 
F.start(); 
S.start(); 
 
try 
{ System.in.read(); } 
catch (java.io.IOException ioe) 
{ } 
F.stop(); 
S.stop(); 
} 
public synchronized void setnumber(int newnum) 
{ 
MyNum = newnum; 
} 
public synchronized int getnumber() 
{ 
return MyNum; 
} 
} 
class RThread extends Thread 
{ 
private String message; 
private int duration; 
 
public RThread(String m, int d) 
{ 
message = m; 
duration = d; 
} 
public void run() 
{ 
try 
{ 
while(true) 
{ 
System.out.println(message); 
try 
{ 
sleep(duration); 
} 
catch (InterruptedException ie) 
{ 
System.out.println("Interrupted&quot

; 
return; 
} 
} 
} 
finally 
{ 
System.out.println(message+" shut down&quot

; 
} 
} 
} 
 
(this is just an example i'm learning with) 
now what I want to be able to do, is have the thread be able 
to call the setnumber, and getnumber located in the main/parent thread. but i do not know how to get ahold of it. 
(in C++ i would not normally just make a class pointer of the parent type, and assign its location, but pointers dont exist in java, and so on) Karl <a href=mailto:kb244@kb244.8m.com>kb244@kb244.8m.com</a> <a href=

http://kb244.8m.com>

</a> Experienced in , or have messed with : VC++, Borland C++ Builder, VJ++6(starting),VB-Dos, VB1 thru VB6, Delphi 3 pro, Borland C++ 3(DOS), Borland C++ 4.5, HTML, ASP(somewhat), QBasic(least i didnt start with COBOL)

Otto · Mar 23, 2000

Hi! 
 
You have two ways (minimum

): 
Make the MyNum, setnumber and getnumber to static, and from the thread just call TCon.setnumber(); 
static int MyNum; 
public static synchronized void setnumber(int newnum) 
public static synchronized int getnumber() 
 
Or create a TCon class in the main, modify the constructor of RThread, give an other parameter (TCon parent) to it, and store it a local reference, and when call: parent.setnumber(); 
 
class RThread extends Thread { 
private String message; 
private int duration; 
private TCon parent; 
 
public RThread(String m, int d, TCon parent) 
{ 
message = m; 
duration = d; 
this.parent=parent; 
} 
 
public static void main (String[] args) { 
TCon tc=new TCon(); 
 
Thread F = new RThread("T1", 250, tc); 
Thread S = new RThread("T2", 750, tc); 
..... 
 
Good luck. Bye, Otto.

Karl Blessing · Mar 24, 2000

hmm thanks, Just the idea of thinking Pointers arnt supported in Java was making my brain slush, hehe, so i kept thinking "does that mean no reference?" Karl <a href=mailto:kb244@kb244.8m.com>kb244@kb244.8m.com</a> <a href=

http://kb244.8m.com>

</a> Experienced in , or have messed with : VC++, Borland C++ Builder, VJ++6(starting),VB-Dos, VB1 thru VB6, Delphi 3 pro, Borland C++ 3(DOS), Borland C++ 4.5, HTML, ASP(somewhat), QBasic(least i didnt start with COBOL)

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Multithreading, need help figuring out how to reach the parent 1

Karl Blessing

Programmer

Otto

Programmer

Karl Blessing

Programmer

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