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Using Throwable to trace the origin of an object

When using components decoupled by queues or other intermediate data stores, it can be a pain to trace the origin of faulty data in the queue. In languages with decent support for stack traces, however, it's easy. In Java, you just add a temporary field
public final Throwable createdBy = new Throwable();
to the class in question. Or, if you need to know who enqueued it where, you vary the creation of the Throwable accordingly. (See example 8-5 of logging in the Red Hat Web Application Framework, too.)

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