UnixDomainSocketsUtil.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.  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,
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 *
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package sun.nio.ch;

import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.security.AccessController;
import java.security.PrivilegedAction;
import sun.net.NetProperties;
import jdk.internal.util.StaticProperty;

class UnixDomainSocketsUtil {
    private UnixDomainSocketsUtil() { }

    static Charset getCharset() {
        return StandardCharsets.UTF_8;
    }

    /**
     * Return the temp directory for storing automatically bound
     * server sockets.
     *
     * On Windows we search the following directories in sequence:
     *
     * 1. ${jdk.net.unixdomain.tmpdir} if set as system property
     * 2. ${jdk.net.unixdomain.tmpdir} if set as net property
     * 3. %TEMP%
     * 4. ${java.io.tmpdir}
     */
    @SuppressWarnings("removal")
    static String getTempDir() {
        PrivilegedAction<String> action = () -> {
            String s = NetProperties.get("jdk.net.unixdomain.tmpdir");
            if (s != null) {
                return s;
            }
            String temp = System.getenv("TEMP");
            if (temp != null) {
                return temp;
            }
            return StaticProperty.javaIoTmpDir();
        };
        return AccessController.doPrivileged(action);
    }
}