/*
 * Copyright (c) 2020, Red Hat, Inc.
 * 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.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * 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.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package sun.net;

import java.net.SocketOption;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
import static jdk.net.ExtendedSocketOptions.TCP_KEEPCOUNT;
import static jdk.net.ExtendedSocketOptions.TCP_KEEPIDLE;
import static jdk.net.ExtendedSocketOptions.TCP_KEEPINTERVAL;

public class ExtendedOptionsHelper {

    private static final boolean keepAliveOptSupported =
            ExtendedOptionsImpl.keepAliveOptionsSupported();
    private static final Set<SocketOption<?>> extendedOptions = options();

    private static Set<SocketOption<?>> options() {
        Set<SocketOption<?>> options = new HashSet<>();
        if (keepAliveOptSupported) {
            options.add(TCP_KEEPCOUNT);
            options.add(TCP_KEEPIDLE);
            options.add(TCP_KEEPINTERVAL);
        }
        return Collections.unmodifiableSet(options);
    }

    public static Set<SocketOption<?>> keepAliveOptions() {
        return extendedOptions;
    }
}
