/*

 * Copyright (c) 2008, 2012, 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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package sun.font;

import java.awt.AWTError;

import java.awt.Font;

import java.awt.GraphicsEnvironment;

import java.awt.Toolkit;

import java.security.AccessController;

import java.security.PrivilegedAction;

import sun.security.action.GetPropertyAction;

/**

 * Factory class used to retrieve a valid FontManager instance for the current

 * platform.

 *

 * A default implementation is given for Linux, Solaris and Windows.

 * You can alter the behaviour of the {@link #getInstance()} method by setting

 * the {@code sun.font.fontmanager} property. For example:

 * {@code sun.font.fontmanager=sun.awt.X11FontManager}

 */

public final class FontManagerFactory {

    /** Our singleton instance. */

    private static FontManager instance = null;

    private static final String DEFAULT_CLASS;

    static {

        if (FontUtilities.isWindows) {

            DEFAULT_CLASS = "sun.awt.Win32FontManager";

        } else if (FontUtilities.isMacOSX) {

            DEFAULT_CLASS = "sun.font.CFontManager";

            } else {

            DEFAULT_CLASS = "sun.awt.X11FontManager";

            }

    }

    /**

     * Get a valid FontManager implementation for the current platform.

     *

     * @return a valid FontManager instance for the current platform

     */

    public static synchronized FontManager getInstance() {

        if (instance != null) {

            return instance;

        }

        AccessController.doPrivileged(new PrivilegedAction() {

            public Object run() {

                try {

                    String fmClassName =

                            System.getProperty("sun.font.fontmanager",

                                               DEFAULT_CLASS);

                    ClassLoader cl = ClassLoader.getSystemClassLoader();

                    Class fmClass = Class.forName(fmClassName, true, cl);

                    instance = (FontManager) fmClass.newInstance();

                } catch (ClassNotFoundException |

                         InstantiationException |

                         IllegalAccessException ex) {

                    throw new InternalError(ex);

                }

                return null;

            }

        });

        return instance;

    }

}