src/jdk.internal.vm.compiler/share/classes/org.graalvm.graphio/src/org/graalvm/graphio/GraphTypes.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * 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).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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package org.graalvm.graphio;

/**
 * Special support for dealing with enums. Normally one can represent various {@link GraphOutput
 * graph} enum values with real {@link Enum} instances. In case this is not possible, the
 * {@link GraphOutput.Builder} allows one to
 * {@link GraphOutput.Builder#types(org.graalvm.graphio.GraphTypes) register} an implementation of
 * this interface to treat them specially.
 */
public interface GraphTypes {
    /**
     * Recognizes an
     * <q>enum</q> object. If the <code>enumValue</code> object represents an enum, then an object
     * that represents its class shall be returned.
     *
     * @param enumValue the value to test
     * @return <code>null</code> if the value isn't enum, otherwise its class
     */
    Object enumClass(Object enumValue);

    /**
     * Ordinal of an enum. If the <code>obj</code> represents an enum, then return its ordinal
     * number otherwise return <code>-1</code>
     *
     * @param obj the value to test
     * @return <code>-1</code> if the obj isn't enum, otherwise its ordinal number
     */
    int enumOrdinal(Object obj);

    /**
     * All possible values of an enum. If the provided <code>maybeEnumClass</code> object represents
     * an enum, then compute enum value names in ordinal order and return them as a string array.
     * Otherwise return <code>null</code>
     *
     * @param maybeEnumClass the class to test
     * @return <code>null</code> if the clazz isn't an enum, otherwise names of its values
     */
    String[] enumTypeValues(Object maybeEnumClass);

    /**
     * Finds Java type name for a given class.
     *
     * @param maybeClass object representing the class
     * @return the type name of the class or <code>null</code> if the parameter doesn't represent a
     *         class
     */
    String typeName(Object maybeClass);
}