object without reference and gc()

[asit]

Consider the following code

class NewThread implements Runnable {

Thread t;

NewThread(String name) {
t = new Thread(this,name);
System.out.println("New thread : " + t);
t.start();
}

public void run() {
try {
for(int i=0; i<5; i++) {
System.out.println(this + " : " + i);
Thread.sleep(500);
}
}catch(InterruptedException e) {
System.out.println("Child interrupted");
}
System.out.println("Child thread exiting");
}
}

public class MyThread {

public static void main(String args[] ) {

Runtime r = Runtime.getRuntime();
new NewThread("Ok1");
new NewThread("Ok2");
new NewThread("Ok3");

r.gc();

try {
Thread.sleep(1000);
}catch(InterruptedException e) {
System.out.println("Main thread interrupted");
}

System.out.println("Main thread exiting");
}

}

In MyThread class, inside main(), I am creating three objects of
NewThread class without storing there references. Hence when I am
calling garbage collector, all these objects should be killed. But in
reality it is not happening. Can anyone help me ???

 

[grendal]

In MyThread class, inside main(), I am creating three objects of
NewThread class without storing there references. Hence when I am
calling garbage collector, all these objects should be killed. But in
reality it is not happening. Can anyone help me ???

In addition to what Patricia said, even calling gc() isn't going to
mean that your object will be garbage collected.

 

[Ratnesh Maurya]

In addition to what Patricia said, even calling gc() isn't going to
mean that your object will be garbage collected.

Yes Grendal,

I would like to rephrase what you said, calling gc() doesn't
guarantees that it will run the garbage collection. Its totally in
control of runtime.

Regards,
-Ratnesh
S7 Software

 

[charlesbos73]

I would like to rephrase what you said,
...
Its totally in control of runtime.

"Its totally in control of runtime."

Thanks for rephrasing.

 

[Lew]

"Its totally in control of runtime."

Thanks for rephrasing.

"It's ..."

 

[Roedy Green]

In MyThread class, inside main(), I am creating three objects of
NewThread class without storing there references. Hence when I am
calling garbage collector, all these objects should be killed. But in
reality it is not happening. Can anyone help me ???

Threads don't get gced until they complete. The OS has a reference to
them. How do you know the dead thread objects are not being GCed?
--
Roedy Green Canadian Mind Products
http://mindprod.com

"Species evolve exactly as if they were adapting as best they could to a changing world, and not at all as if they were moving toward a set goal."
~ George Gaylord Simpson

 

[Arne Vajhøj]

Threads don't get gced until they complete. The OS has a reference to
them. How do you know the dead thread objects are not being GCed?

The GC has no way of knowing that the OS refers to something.

But the JVM also has a ref - and the GC knows about that.

Arne

 

[Roedy Green]

The GC has no way of knowing that the OS refers to something.

But the JVM also has a ref - and the GC knows about that.

Correct. The object doing the pinning lives in the JVM. It represents
the OS native thread. I was speaking too loosely.
--
Roedy Green Canadian Mind Products
http://mindprod.com

"Species evolve exactly as if they were adapting as best they could to a changing world, and not at all as if they were moving toward a set goal."
~ George Gaylord Simpson

 

[Tris Orendorff]

"It's ..."

.... Monty Python's Flying Cir-cus.


--
Tris Orendorff
[ Anyone naming their child should spend a few minutes checking rhyming slang and dodgy sounding names. Brad and
Angelina failed to do this when naming their kid Shiloh Pitt. At some point, someone at school is going to spoonerise her
name.
Craig Stark ]