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/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.iceberg.expressions;
import java.io.Serializable;
import java.math.BigDecimal;
import java.nio.ByteBuffer;
import java.util.Comparator;
import java.util.UUID;
import org.apache.iceberg.types.Type;
/**
* Represents a literal fixed value in an expression predicate
* @param The Java type of the value wrapped by a {@link Literal}
*/
public interface Literal extends Serializable {
static Literal of(boolean value) {
return new Literals.BooleanLiteral(value);
}
static Literal of(int value) {
return new Literals.IntegerLiteral(value);
}
static Literal of(long value) {
return new Literals.LongLiteral(value);
}
static Literal of(float value) {
return new Literals.FloatLiteral(value);
}
static Literal of(double value) {
return new Literals.DoubleLiteral(value);
}
static Literal of(CharSequence value) {
return new Literals.StringLiteral(value);
}
static Literal of(UUID value) {
return new Literals.UUIDLiteral(value);
}
static Literal of(byte[] value) {
return new Literals.FixedLiteral(ByteBuffer.wrap(value));
}
static Literal of(ByteBuffer value) {
return new Literals.BinaryLiteral(value);
}
static Literal of(BigDecimal value) {
return new Literals.DecimalLiteral(value);
}
/**
* Returns the value wrapped by this literal.
*/
T value();
/**
* Converts this literal to a literal of the given type.
*
* When a predicate is bound to a concrete data column, literals are converted to match the bound
* column's type. This conversion process is more narrow than a cast and is only intended for
* cases where substituting one type is a common mistake (e.g. 34 instead of 34L) or where this
* API avoids requiring a concrete class (e.g., dates).
*
* If conversion to a target type is not supported, this method returns null.
*
* This method may return {@link Literals#aboveMax} or {@link Literals#belowMin} when the target
* type is not as wide as the original type. These values indicate that the containing predicate
* can be simplified. For example, Integer.MAX_VALUE+1 converted to an int will result in
* {@code aboveMax} and can simplify a < Integer.MAX_VALUE+1 to {@link Expressions#alwaysTrue}
*
* @param type A primitive {@link Type}
* @param The Java type of value the new literal contains
* @return A literal of the given type or null if conversion was not valid
*/
Literal to(Type type);
/**
* Return a {@link Comparator} for values.
* @return a comparator for T objects
*/
Comparator comparator();
/**
* Serializes the value wrapped by this literal to binary using the single-value serialization
* format described in the Iceberg table specification.
*
* @return a ByteBuffer that contains the serialized literal value.
*/
default ByteBuffer toByteBuffer() {
throw new UnsupportedOperationException("toByteBuffer is not supported");
}
}