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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.  Oracle designates this
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 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package com.sun.source.tree;

import jdk.internal.javac.PreviewFeature;

/**
 * A tree node for an {@code instanceof} expression.
 *
 * For example:
 * <pre>
 *   <em>expression</em> instanceof <em>type</em>
 * </pre>
 *
 * @jls 15.20.2 Type Comparison Operator instanceof
 *
 * @author Peter von der Ah&eacute;
 * @author Jonathan Gibbons
 * @since 1.6
 */
public interface InstanceOfTree extends ExpressionTree {

    /**
     * Two possible variants of instanceof expressions:
     * <ul>
     * <li> testing types, and
     * <li> performing pattern matching
     * </ul>
     * @since 20
     */
    @PreviewFeature(feature=PreviewFeature.Feature.RECORD_PATTERNS, reflective=true)
    public enum TestKind {
        /** instanceof only testing a type */
        TYPE,
        /** instanceof doing a pattern matching */
        PATTERN
    }

    /**
     * Returns the expression to be tested.
     * @return the expression
     */
    ExpressionTree getExpression();

    /**
     * Returns the type for which to check.
     * @return the type
     * @see #getPattern()
     */
    Tree getType();

    /**
     * Returns the tested pattern, or null if this instanceof does not use
     * a pattern.
     *
     * <p>For instanceof with a pattern, i.e. in the following form:
     * <pre>
     *   <em>expression</em> instanceof <em>type</em> <em>variable name</em>
     * </pre>
     * returns the pattern.
     *
     * <p>For instanceof without a pattern, i.e. in the following form:
     * <pre>
     *   <em>expression</em> instanceof <em>type</em>
     * </pre>
     * returns null.
     *
     * @return the tested pattern, or null if this instanceof does not use a pattern
     * @since 16
     */
    PatternTree getPattern();

    /**
     * Returns the kind of this instanceof expression.
     *
     * @return the kind of this instanceof expression
     * @since 20
     */
    @PreviewFeature(feature=PreviewFeature.Feature.RECORD_PATTERNS, reflective=true)
    TestKind getTestKind();
}