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arizona (1) [Avatar] Offline
I am trying to understand the @TransactionScoped Annotation. I build a simple app and annotated the class Gauge with it:

public class Gauge {
void measure() {

private int temp = 0;

public int temperature() {
return temp;

Launching the app like this shows me no real benefit of this annotation (i think it is not working).

public class PowerStation {

Transaction transaction;
Chamber chamber1 = new Chamber();
Chamber chamber2 = new Chamber();
Chamber chamber3 = new Chamber();

public void start() {

TransactionModule module = new TransactionModule();
Injector injector = Guice.createInjector(new Module[]{module});

boolean failed = false;
try {;;;

} catch (StartFailedException e) {
failed = true;
} finally {
if (failed) {
} else {

So what is wrong?