/*
 * Copyright (c) 2002, 2004, 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 sun.security.action;

import java.io.*;

import java.security.PrivilegedExceptionAction;

/**
 * A convenience class for opening a FileInputStream as a privileged action.
 *
 * @author Andreas Sterbenz
 */
public class OpenFileInputStreamAction
        implements PrivilegedExceptionAction<FileInputStream> {

    private final File file;

    // Return null if the file doesn't exist
    private final boolean graceful;

    public OpenFileInputStreamAction(File file) {
        this(file, false);
    }

    public OpenFileInputStreamAction(File file, boolean graceful) {
        this.file = file;
        this.graceful = graceful;
    }

    public OpenFileInputStreamAction(String filename) {
        this.file = new File(filename);
        this.graceful = false;
    }

    public FileInputStream run() throws Exception {
        if (graceful) {
            try {
                if (file.exists()) {
                    return new FileInputStream(file);
                } else {
                    return null;
                }
            } catch (FileNotFoundException e) {
                // couldn't find it, oh well.
                return null;
            }
        } else {
            return new FileInputStream(file);
        }
    }
}