Synchronization Issues with TransientComponentAdapter

TransientComponentAdapter.getComponentInstance() should/must be synchronized.

Why:

package pico;

import junit.framework.TestCase;
import org.picocontainer.defaults.DefaultPicoContainer;
import org.picocontainer.defaults.TransientComponentAdapter;

public class TimingProblemTestCase extends TestCase
{
public void testTimingProblems() throws Exception
{
final DefaultPicoContainer pico = new DefaultPicoContainer();
pico.registerComponentImplementation(VerySlow.class);
pico.registerComponent(new TransientComponentAdapter("key", SomethingFast.class));

Runnable test = new Runnable() {
public void run()

{ SomethingFast fast = (SomethingFast) pico.getComponentInstance("key"); }

};

Thread t1 = new Thread(test);
Thread t2 = new Thread(test);

t1.start();
t2.start();

Thread.currentThread().join();
}

public static class VerySlow
{
public VerySlow() throws InterruptedException

{ // think of something that queries remote objects // or anything that _might_ be slow Thread.sleep(10000); }

}

public static class SomethingFast
{
private final VerySlow slow;
public SomethingFast(VerySlow slow)

{ this.slow = slow; }

}
}

the resulting exception:

org.picocontainer.defaults.CyclicDependencyException: Cyclic dependency: pico.TimingProblemTestCase$SomethingFast(pico.TimingProblemTestCase$VerySlow)
at org.picocontainer.defaults.TransientComponentAdapter.instantiateComponent(TransientComponentAdapter.java:160)
at org.picocontainer.defaults.TransientComponentAdapter.getComponentInstance(TransientComponentAdapter.java:153)
at org.picocontainer.defaults.DefaultPicoContainer.getComponentInstance(DefaultPicoContainer.java:165)
at pico.TimingProblemTestCase$1.run(TimingProblemTestCase.java:27)
at java.lang.Thread.run(Thread.java:534)

One might argue that the instantiation process is required to be fast but nonetheless we live in a multithreaded world and even if its a very fast constructor the problem remains.