spike-liu commented on a change in pull request #678: URL: https://github.com/apache/lucene/pull/678#discussion_r807570862
########## File path: lucene/core/src/java/org/apache/lucene/index/Terms.java ########## @@ -124,6 +124,69 @@ protected BytesRef nextSeekTerm(BytesRef term) throws IOException { /** Zero-length array of {@link Terms}. */ public static final Terms[] EMPTY_ARRAY = new Terms[0]; + /** An empty {@link Terms} which returns no terms */ + public static Terms emptyTerms() { + return new Terms() { + @Override + public TermsEnum iterator() throws IOException { + return TermsEnum.EMPTY; + } + + @Override + public long size() throws IOException { + return 0; + } + + @Override + public long getSumTotalTermFreq() throws IOException { + return 0; + } + + @Override + public long getSumDocFreq() throws IOException { + return 0; + } + + @Override + public int getDocCount() throws IOException { + return 0; + } + + @Override + public boolean hasFreqs() { + return false; + } + + @Override + public boolean hasOffsets() { + return false; + } + + @Override + public boolean hasPositions() { + return false; + } + + @Override + public boolean hasPayloads() { + return false; + } + }; + } + + /** + * Returns the {@link Terms} index for this field, or {@link #emptyTerms} if it has none. + * @return terms instance, or an empty instance if {@code field} does not exist in this reader Review comment: Thanks for your kindly instruction. Fixed. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: issues-unsubscr...@lucene.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@lucene.apache.org For additional commands, e-mail: issues-h...@lucene.apache.org