Java API

Package:

org.apache.paimon.index.fulltext

Main classes:

• FullTextIndexWriter
• FullTextIndexReader
• FullTextSearchResult
• FullTextIndexInput
• FullTextIndexOutput

Example:

Map<String, String> options = Collections.singletonMap("text-fields", "title,body");
try (FullTextIndexWriter writer = FullTextIndexWriter.create(options)) {
    Map<String, String> fields = new LinkedHashMap<>();
    fields.put("title", "Apache Paimon");
    fields.put("body", "lake storage");
    writer.addDocument(1L, fields);
    writer.writeIndex(output);
}

try (FullTextIndexReader reader = new FullTextIndexReader(input)) {
    reader.prewarm();
    FullTextSearchResult result =
            reader.search("{\"match\":{\"query\":\"paimon\"}}", 10);
    FullTextSearchResult filtered =
            reader.search("{\"match\":{\"query\":\"paimno\",\"column\":\"title\",\"fuzziness\":1}}",
                    10,
                    roaringFilterBytes);
    FullTextReadMetrics metrics = reader.readMetrics();
}

search() accepts the query DSL as a JSON string. match supports column, operator, boost, fuzziness, max_expansions, and prefix_length. If column is omitted, a multi-field index searches all indexed text fields. Use "fuzziness":"auto" for auto fuzziness. Boolean and boost-demotion queries use the same JSON DSL.

roaringFilterBytes must be a serialized 64-bit Roaring bitmap (RoaringTreemap) containing the allowed row ids. The filter is applied during Tantivy collection, before the top results are selected.

prewarm() eagerly initializes the underlying search reader and archive cache before a query burst. readMetrics() returns a snapshot with preadCalls, preadRanges, preadBytes, cacheHits, cacheMisses, cacheEvictions, and cachedBlocks.

Input reads:

• Implement FullTextIndexInput.pread(long position, byte[] buffer, int offset, int length) as a single positional read. Rust owns any batching or parallelism above this callback.
• The implementation must be safe for concurrent calls. Synchronize inside pread if the backing input keeps mutable state.

Native loading:

• Set PAIMON_FTINDEX_JNI_LIB_PATH to the full path of libpaimon_ftindex_jni.dylib / .so, or
• put the library on java.library.path as paimon_ftindex_jni.