/*

 * Copyright (c) 2010, 2014, Oracle and/or its affiliates. All rights reserved.

 * 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 jdk.nashorn.internal.runtime;

import java.io.ByteArrayInputStream;

import java.io.IOException;

import java.io.ObjectInputStream;

import java.security.AccessController;

import java.security.PrivilegedAction;

import java.util.zip.InflaterInputStream;

import jdk.nashorn.internal.ir.FunctionNode;

/**

 * This static utility class performs deserialization of FunctionNode ASTs from a byte array.

 * The format is a standard Java serialization stream, deflated.

 */

final class AstDeserializer {

    static FunctionNode deserialize(final byte[] serializedAst) {

        return AccessController.doPrivileged(new PrivilegedAction<FunctionNode>() {

            @Override

            public FunctionNode run() {

                try {

                    return (FunctionNode)new ObjectInputStream(new InflaterInputStream(

                        new ByteArrayInputStream(serializedAst))).readObject();

                } catch (final ClassNotFoundException | IOException e) {

                    // This is internal, can't happen

                    throw new AssertionError("Unexpected exception deserializing function", e);

                }

            }

        });

    }

}