connector/expressions/Literal.java

0001 /*
0002  * Licensed to the Apache Software Foundation (ASF) under one or more
0003  * contributor license agreements.  See the NOTICE file distributed with
0004  * this work for additional information regarding copyright ownership.
0005  * The ASF licenses this file to You under the Apache License, Version 2.0
0006  * (the "License"); you may not use this file except in compliance with
0007  * the License.  You may obtain a copy of the License at
0008  *
0009  *    http://www.apache.org/licenses/LICENSE-2.0
0010  *
0011  * Unless required by applicable law or agreed to in writing, software
0012  * distributed under the License is distributed on an "AS IS" BASIS,
0013  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
0014  * See the License for the specific language governing permissions and
0015  * limitations under the License.
0016  */
0017
0018 package org.apache.spark.sql.connector.expressions;
0019
0020 import org.apache.spark.annotation.Evolving;
0021 import org.apache.spark.sql.types.DataType;
0022
0023 /**
0024  * Represents a constant literal value in the public expression API.
0025  * <p>
0026  * The JVM type of the value held by a literal must be the type used by Spark's InternalRow API for
0027  * the literal's {@link DataType SQL data type}.
0028  *
0029  * @param <T> the JVM type of a value held by the literal
0030  * @since 3.0.0
0031  */
0032 @Evolving
0033 public interface Literal<T> extends Expression {
0034   /**
0035    * Returns the literal value.
0036    */
0037   T value();
0038
0039   /**
0040    * Returns the SQL data type of the literal.
0041    */
0042   DataType dataType();
0043 }