Pushdown for LIKE (LIST) (#129557)

Improved performance of LIKE (LIST)  by pushing an Automaton to do the evaluation down to Lucine.

server/src/main/java/org/elasticsearch/index/query/AutomatonQueryBuilder.java

@@ -0,0 +1,104 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the "Elastic License
+ * 2.0", the "GNU Affero General Public License v3.0 only", and the "Server Side
+ * Public License v 1"; you may not use this file except in compliance with, at
+ * your election, the "Elastic License 2.0", the "GNU Affero General Public
+ * License v3.0 only", or the "Server Side Public License, v 1".
+ */
+
+package org.elasticsearch.index.query;
+
+import org.apache.lucene.index.Term;
+import org.apache.lucene.search.AutomatonQuery;
+import org.apache.lucene.search.Query;
+import org.apache.lucene.util.automaton.Automaton;
+import org.elasticsearch.TransportVersion;
+import org.elasticsearch.common.Strings;
+import org.elasticsearch.common.io.stream.StreamOutput;
+import org.elasticsearch.xcontent.XContentBuilder;
+
+import java.io.IOException;
+import java.io.UnsupportedEncodingException;
+import java.util.Objects;
+
+/**
+ * Implements an Automaton query, which matches documents based on a Lucene Automaton.
+ * It does not support serialization or XContent representation.
+ */
+public class AutomatonQueryBuilder extends AbstractQueryBuilder<AutomatonQueryBuilder> implements MultiTermQueryBuilder {
+    private final String fieldName;
+    private final Automaton automaton;
+    private final String description;
+
+    public AutomatonQueryBuilder(String fieldName, Automaton automaton, String description) {
+        if (Strings.isEmpty(fieldName)) {
+            throw new IllegalArgumentException("field name is null or empty");
+        }
+        if (automaton == null) {
+            throw new IllegalArgumentException("automaton cannot be null");
+        }
+        this.fieldName = fieldName;
+        this.automaton = automaton;
+        this.description = description;
+    }
+
+    @Override
+    public String fieldName() {
+        return fieldName;
+    }
+
+    @Override
+    public String getWriteableName() {
+        throw new UnsupportedOperationException("AutomatonQueryBuilder does not support getWriteableName");
+    }
+
+    @Override
+    protected void doWriteTo(StreamOutput out) throws IOException {
+        throw new UnsupportedEncodingException("AutomatonQueryBuilder does not support doWriteTo");
+    }
+
+    @Override
+    protected void doXContent(XContentBuilder builder, Params params) throws IOException {
+        throw new UnsupportedEncodingException("AutomatonQueryBuilder does not support doXContent");
+    }
+
+    @Override
+    protected Query doToQuery(SearchExecutionContext context) throws IOException {
+        return new AutomatonQueryWithDescription(new Term(fieldName), automaton, description);
+    }
+
+    @Override
+    protected int doHashCode() {
+        return Objects.hash(fieldName, automaton, description);
+    }
+
+    @Override
+    protected boolean doEquals(AutomatonQueryBuilder other) {
+        return Objects.equals(fieldName, other.fieldName)
+            && Objects.equals(automaton, other.automaton)
+            && Objects.equals(description, other.description);
+    }
+
+    @Override
+    public TransportVersion getMinimalSupportedVersion() {
+        throw new UnsupportedOperationException("AutomatonQueryBuilder does not support getMinimalSupportedVersion");
+    }
+
+    static class AutomatonQueryWithDescription extends AutomatonQuery {
+        private final String description;
+
+        AutomatonQueryWithDescription(Term term, Automaton automaton, String description) {
+            super(term, automaton);
+            this.description = description;
+        }
+
+        @Override
+        public String toString(String field) {
+            if (this.field.equals(field)) {
+                return description;
+            }
+            return this.field + ":" + description;
+        }
+    }
+}