### Question:
SingleFileIndexDirectory extends ColumnIndexDirectory { @Override public void removeIndex(String columnName, ColumnIndexType indexType) { throw new UnsupportedOperationException( "Index removal is not supported for single file index format. Requested colum: " + columnName + " indexType: " + indexType); } SingleFileIndexDirectory(File segmentDirectory, SegmentMetadataImpl metadata, ReadMode readMode); @Override PinotDataBuffer getBuffer(String column, ColumnIndexType type); @Override PinotDataBuffer newBuffer(String column, ColumnIndexType type, long sizeBytes); @Override boolean hasIndexFor(String column, ColumnIndexType type); @Override void close(); @Override void removeIndex(String columnName, ColumnIndexType indexType); @Override boolean isIndexRemovalSupported(); @Override String toString();  }### Answer:
@Test(expectedExceptions = UnsupportedOperationException.class) public void testRemoveIndex() throws IOException, ConfigurationException { try (SingleFileIndexDirectory sfd = new SingleFileIndexDirectory(TEMP_DIR, segmentMetadata, ReadMode.mmap)) { sfd.newBuffer("col1", ColumnIndexType.DICTIONARY, 1024); Assert.assertFalse(sfd.isIndexRemovalSupported()); sfd.removeIndex("col1", ColumnIndexType.DICTIONARY); } }