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// Class DefaultExceptionReporter
public class DefaultExceptionReporter implements ExceptionReporter {
  public DefaultExceptionReporter(ExceptionReporter er) {
    // ...
  }


  // Should be called after subclass's initialization is over
  public final void setExceptionReporter() {
    setExceptionReporter(this); // Registers this exception reporter 
  }

  // Implementation of report()
}

The subclass uses a setReporter() method After constructing an object of class DefaultExceptionReporter, or a subclass thereof, you must explicitly call DefaultExceptionReporter.setExceptionReporter() to set the exception reporter:.

// Class MyExceptionReporter derives from DefaultExceptionReporter
public class MyExceptionReporter extends DefaultExceptionReporter {
  private final Logger logger;
  
  public MyExceptionReporter(ExceptionReporter er) {
    super(er); // Calls superclass's constructor
    logger = Logger.getLogger("com.organization.Log");
  }

  public void setReporter() { // Sets the exception reporter
    super.setExceptionReporter(); 
  }
}
}

This ensures that the reporter cannot be set before the constructor has This ensures that the reporter cannot be set before the constructor has fully initialized the subclass.

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Compliant Solution (thread)

Wiki MarkupIn this compliant solution, even though the thread is created and started in a method, not in the constructor. Consequently, the this item is never passed to an alien method during the constructor.

class ThreadStarter implements Runnable {
  public ThreadStarter() {
    // ...
  }

  public void startThread() {    
    thread = new Thread(this);
    thread.start();
  }

  public void run() {
    // ...
  }
}

Exceptions

*CON14-J:EX1*: It may be safe to invoke methods or constructors provided by the JRE that are known to handle the {{this}} object safely. In this code example, even though a thread referencing {{this}} thread is created in the constructor, it is not started until its {{start()}} method is called from method {{startThread()}} \[[Goetz 02|AA. Java References#Goetz 02]\], \[[Goetz 06|AA. Java References#Goetz 06]\].

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