/**
* Calls a particular callback function. The function must previously have been checked using
* checkCallback().
*
* @param sCallback Name of callback
* @throws OmException If the callback throws an exception or there was an error calling it
*/
public void callback(String sCallback) throws OmException {
if (!sCheckedCallbacks.contains(sCallback))
throw new OmDeveloperException(
"Error running callback " + sCallback + "(): checkCallback was not called");
try {
Method m = getClass().getMethod(sCallback, new Class[0]);
m.invoke(this, new Object[0]);
} catch (InvocationTargetException e) {
if (e.getCause() instanceof OmException) throw (OmException) e.getCause();
else throw new OmException("Exception in callback " + sCallback + "()", e.getCause());
} catch (Exception e) {
throw new OmUnexpectedException(e);
}
}
/**
* Checks that a callback method is present and correctly defined.
*
* <p>Having checked it, you can call it using callback().
*
* @param sCallback Name of callback method
* @throws OmDeveloperException If the method doesn't exist or is defined incorrectly
*/
public void checkCallback(String sCallback) throws OmDeveloperException {
try {
Method m = getClass().getMethod(sCallback, new Class[0]);
if (m.getReturnType() != void.class)
throw new OmDeveloperException("Callback method " + sCallback + "() must return void");
if (!Modifier.isPublic(m.getModifiers()))
throw new OmDeveloperException("Callback method " + sCallback + "() must be public");
if (Modifier.isStatic(m.getModifiers()))
throw new OmDeveloperException("Callback method " + sCallback + "() may not be static");
if (Modifier.isAbstract(m.getModifiers()))
throw new OmDeveloperException("Callback method " + sCallback + "() may not be abstract");
sCheckedCallbacks.add(sCallback);
} catch (NoSuchMethodException e) {
throw new OmDeveloperException("Callback method " + sCallback + "() does not exist");
}
}
