How to use

ISubjectControlContentAssistProcessor

in

org.eclipse.jface.contentassist

  @Override
  public void run() throws Exception {
    processors.forEach(p -> {
      ICompletionProposal[] proposals= p.computeCompletionProposals(viewer, offset);
      if (proposals != null) {
        res.addAll(Arrays.asList(proposals));
      }
      fLastErrorMessage= p.getErrorMessage();
    });
  }
});

  @Override
  public void run() throws Exception {
    result[0]= ((ISubjectControlContentAssistProcessor) p)
        .computeContextInformation(contentAssistSubjectControl, offset);
    fLastErrorMessage= p.getErrorMessage();
  }
});

  @Override
  public boolean isContextInformationValid(int offset) {
    if (fContentAssistSubjectControl != null && fProcessor instanceof ISubjectControlContentAssistProcessor) {
      IContextInformation[] infos= ((ISubjectControlContentAssistProcessor)fProcessor).computeContextInformation(fContentAssistSubjectControl, offset);
      if (infos != null && infos.length > 0) {
        for (IContextInformation info : infos) {
          if (fContextInformation.equals(info))
            return true;
        }
      }
    }
    return false;
  }
}

  @Override
  public void run() throws Exception {
    result[0]= ((ISubjectControlContentAssistProcessor) p)
        .computeCompletionProposals(contentAssistSubjectControl, offset);
    fLastErrorMessage= p.getErrorMessage();
  }
});

  @Override
  public boolean isContextInformationValid(int offset) {
    if (fContentAssistSubjectControl != null && fProcessor instanceof ISubjectControlContentAssistProcessor) {
      IContextInformation[] infos= ((ISubjectControlContentAssistProcessor)fProcessor).computeContextInformation(fContentAssistSubjectControl, offset);
      if (infos != null && infos.length > 0) {
        for (int i= 0; i < infos.length; i++) {
          if (fContextInformation.equals(infos[i]))
            return true;
        }
      }
    }
    return false;
  }
}