
/*
 * Janino - An embedded Java[TM] compiler
 *
 * Copyright (c) 2001-2010 Arno Unkrig. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
 * following conditions are met:
 *
 *    1. Redistributions of source code must retain the above copyright notice, this list of conditions and the
 *       following disclaimer.
 *    2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
 *       following disclaimer in the documentation and/or other materials provided with the distribution.
 *    3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote
 *       products derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.codehaus.janino;

import java.io.IOException;
import java.io.InputStream;

import org.codehaus.commons.compiler.util.resource.Resource;
import org.codehaus.commons.compiler.util.resource.ResourceFinder;
import org.codehaus.commons.nullanalysis.Nullable;
import org.codehaus.janino.util.ClassFile;

/**
 * This {@link org.codehaus.janino.IClassLoader} loads IClasses through a a {@link
 * org.codehaus.commons.compiler.util.resource.ResourceFinder} that designates {@link
 * org.codehaus.janino.util.ClassFile}s.
 */
public
class ResourceFinderIClassLoader extends IClassLoader {
    private final ResourceFinder resourceFinder;

    public
    ResourceFinderIClassLoader(ResourceFinder resourceFinder, @Nullable IClassLoader parentIClassLoader) {
        super(parentIClassLoader);
        this.resourceFinder = resourceFinder;
        this.postConstruct();
    }

    @Override @Nullable protected IClass
    findIClass(String descriptor) throws ClassNotFoundException {
        String className = Descriptor.toClassName(descriptor);

        // Find the class file resource.
        Resource classFileResource = this.resourceFinder.findResource(ClassFile.getClassFileResourceName(className));
        if (classFileResource == null) return null;

        // Open the class file resource.
        InputStream is;
        try {
            is = classFileResource.open();
        } catch (IOException ex) {
            throw new ClassNotFoundException("Opening resource \"" + classFileResource.getFileName() + "\"", ex);
        }

        // Load the IClass from the class file.
        ClassFile cf;
        try {
            cf = new ClassFile(is);
        } catch (IOException e) {
            throw new ClassNotFoundException("Reading resource \"" + classFileResource.getFileName() + "\"", e);
        } finally {
            try { is.close(); } catch (IOException e) {}
        }
        IClass iClass = new ClassFileIClass(cf, this);
        this.defineIClass(iClass);
        return iClass;
    }
}
