/*

 * Copyright (c) 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 org.openjdk.tests.separate;

import java.util.HashMap;

import java.io.File;

import java.io.FileInputStream;

import java.io.IOException;

class DirectedClassLoader extends ClassLoader {

    private HashMap<String,File> loadLocations;

    private File defaultLocation;

    private ClassFilePreprocessor[] preprocessors;

    public DirectedClassLoader(

            HashMap<String,File> locations, File fallback,

            ClassFilePreprocessor ... preprocessors) {

        loadLocations = new HashMap<>(locations);

        defaultLocation = fallback;

        this.preprocessors = preprocessors;

    }

    public DirectedClassLoader(

            File fallback, ClassFilePreprocessor ... preprocessors) {

        loadLocations = new HashMap<>();

        defaultLocation = fallback;

        this.preprocessors = preprocessors;

    }

    public DirectedClassLoader(ClassFilePreprocessor ... preprocessors) {

        this((File)null, preprocessors);

    }

    public void setDefaultLocation(File dir) { this.defaultLocation = dir; }

    public void setLocationFor(String name, File dir) {

        loadLocations.put(name, dir);

    }

    @Override

    protected Class<?> findClass(String name) {

        String path = name.replace(".", File.separator) + ".class";

        File location = loadLocations.get(name);

        if (location == null || !(new File(location, path)).exists()) {

            File def = new File(defaultLocation, path);

            if (def.exists()) {

                return defineFrom(name, new File(location, path));

            }

        } else {

            return defineFrom(name, new File(location, path));

        }

        return null;

    }

    private Class<?> defineFrom(String name, File file) {

        FileInputStream fis = null;

        try {

            try {

                fis = new FileInputStream(file);

                byte[] bytes = new byte[fis.available()];

                int read = fis.read(bytes);

                if (read != bytes.length) {

                    return null;

                }

                if (preprocessors != null) {

                    for (ClassFilePreprocessor cfp : preprocessors) {

                        bytes = cfp.preprocess(name, bytes);

                    }

                 }

                return defineClass(name, bytes, 0, bytes.length);

            } finally {

                fis.close();

            }

        } catch (IOException e) {}

        return null;

    }

}