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Using completionStage Properly

Hi,
There is following code -

   public CompletionStage<Void> addEmail(Long userID, String email) {

      CompletableFuture<GetMappingResponsePayload> getMappingResponsePayloadCompletionStage =
              (CompletableFuture<GetMappingResponsePayload>) addressResolver.getEmailMapping(email);

    return addressResolver.addEmailMapping(email, userID)
        .thenCompose(__ -> emailsDao.upsertEmail(userID, email, true));

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I want to fetch the object GetMappingResponsePayload from above.
The getEmailMapping function is a synchronous call so when the code gets executed the result will be there.
To give the context there is a Boolean attribute inside GetMappingResponsePayload and based on that
i want to return an exceptionallyCompletedFuture in case the value is false.
otherwise the next return statement is executed.
How do i achieve this neatly

Thanks

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Rohit Bajaj

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There is one more way that i figured out. I wanted to avoid catching Exception. Because the future would be complete and get method throws exception so here is what i did... Please advice on the code below :

 final Boolean[] isEmailPresentForDifferentJID = {false};
    addressResolver.getEmailMapping(email).
        thenAccept((getMappingResponsePayload) -> {
          JID jidFromEmail = getMappingResponsePayload.getJID();
          JID jidFromUserID = UserService.getNodeJID(userID);
          if (jidFromEmail != null && !jidFromUserID.equals(jidFromEmail))
            isEmailPresentForDifferentJID[0] = true;
        });
    return isEmailPresentForDifferentJID[0];