com.acciente.commons.loader.JavaCompiledClassDef.java Source code

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Here is the source code for com.acciente.commons.loader.JavaCompiledClassDef.java

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/*
 * Copyright 2008-2013 Acciente, LLC
 *
 * Acciente, LLC licenses this file to you under the
 * Apache License, Version 2.0 (the "License"); you
 * may not use this file except in compliance with the
 * License. You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in
 * writing, software distributed under the License is
 * distributed on an "AS IS" BASIS, WITHOUT WARRANTIES
 * OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing
 * permissions and limitations under the License.
 */
package com.acciente.commons.loader;

import org.apache.commons.io.FileUtils;

import java.io.File;
import java.io.IOException;
import java.util.Set;

/**
 * An implementation of a ClassDef backed by compiled Java class files.
 *
 * @see com.acciente.commons.loader.ClassDef
 *
 * @created Feb 29, 2008
 *
 * @author Adinath Raveendra Raj
 */
public class JavaCompiledClassDef implements ClassDef {
    // compiled file data
    private File _oCompiledFile;
    private long _iLastModifiedTimeAtLastLoad;

    // class data
    private String _sClassName;
    private byte[] _ayClassByteCode;
    private String[] _asReferencedClassNames;

    JavaCompiledClassDef(String sClassName, File oCompiledFile) throws ClassNotFoundException {
        _sClassName = sClassName;
        _oCompiledFile = oCompiledFile;

        loadCompiledClassFile();
    }

    public String getClassName() {
        return _sClassName;
    }

    public boolean isModified() {
        return (_oCompiledFile.lastModified() != _iLastModifiedTimeAtLastLoad);
    }

    public void reload() throws ClassNotFoundException {
        loadCompiledClassFile();
    }

    public byte[] getByteCode() {
        return _ayClassByteCode;
    }

    public ClassDef[] getBundledClassDefs() {
        return null;
    }

    public String[] getReferencedClasses() {
        return _asReferencedClassNames;
    }

    private void loadCompiledClassFile() throws ClassNotFoundException {
        try {
            // checkpoint the compiled file's modified date before the compile
            long iLastModifiedTimeAtLastLoad = _oCompiledFile.lastModified();

            _ayClassByteCode = FileUtils.readFileToByteArray(_oCompiledFile);

            _iLastModifiedTimeAtLastLoad = iLastModifiedTimeAtLastLoad;

            readReferencedClasses(_ayClassByteCode, _oCompiledFile.getName());
        } catch (IOException e) {
            throw new ClassNotFoundException("Error loading class definition", e);
        }
    }

    private void readReferencedClasses(byte[] ayClassByteCode, String sFilename) throws IOException {
        Set oReferencedClassNameSet = new ClassFile(ayClassByteCode).getReferencedClasses();

        // convert the list to an array
        _asReferencedClassNames = new String[oReferencedClassNameSet.size()];
        oReferencedClassNameSet.toArray(_asReferencedClassNames);
    }
}

// EOF