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This module contains the Table/SQL API for writing table programs within the table ecosystem using the Java programming language.

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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.flink.table.api;

import org.apache.flink.annotation.PublicEvolving;
import org.apache.flink.table.expressions.Expression;
import org.apache.flink.table.expressions.ExpressionParser;

/**
 * Sliding window on time.
 */
@PublicEvolving
public final class SlideWithSizeAndSlideOnTime {

	private final Expression timeField;
	private final Expression size;
	private final Expression slide;

	SlideWithSizeAndSlideOnTime(
		Expression timeField,
		Expression size,
		Expression slide) {
		this.timeField = timeField;
		this.size = size;
		this.slide = slide;
	}

	/**
	 * Assigns an alias for this window that the following {@code groupBy()} and {@code select()}
	 * clause can refer to. {@code select()} statement can access window properties such as window
	 * start or end time.
	 *
	 * @param alias alias for this window
	 * @return this window
	 */
	public SlideWithSizeAndSlideOnTimeWithAlias as(String alias) {
		return as(ExpressionParser.parseExpression(alias));
	}

	/**
	 * Assigns an alias for this window that the following {@code groupBy()} and {@code select()}
	 * clause can refer to. {@code select()} statement can access window properties such as window
	 * start or end time.
	 *
	 * @param alias alias for this window
	 * @return this window
	 */
	public SlideWithSizeAndSlideOnTimeWithAlias as(Expression alias) {
		return new SlideWithSizeAndSlideOnTimeWithAlias(alias, timeField, size, slide);
	}
}