/*
 * Bytecode Analysis Framework
 * Copyright (C) 2003-2007 University of Maryland
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package edu.umd.cs.findbugs.classfile.engine.bcel;

import org.apache.bcel.classfile.Code;
import org.apache.bcel.classfile.Method;

import edu.umd.cs.findbugs.ba.BytecodeScanner;
import edu.umd.cs.findbugs.classfile.CheckedAnalysisException;
import edu.umd.cs.findbugs.classfile.IAnalysisCache;
import edu.umd.cs.findbugs.classfile.MethodDescriptor;

/**
 * Analysis engine to produce UnpackedCode objects for analyzed methods.
 *
 * @author David Hovemeyer
 */
public class UnpackedCodeFactory extends AnalysisFactory<UnpackedCode> {
    /**
     * Constructor.
     */
    public UnpackedCodeFactory() {
        super("unpacked bytecode", UnpackedCode.class);
    }

    /*
     * (non-Javadoc)
     *
     * @see
     * edu.umd.cs.findbugs.classfile.IAnalysisEngine#analyze(edu.umd.cs.findbugs
     * .classfile.IAnalysisCache, java.lang.Object)
     */
    @Override
    public UnpackedCode analyze(IAnalysisCache analysisCache, MethodDescriptor descriptor) throws CheckedAnalysisException {
        Method method = getMethod(analysisCache, descriptor);
        Code code = method.getCode();
        if (code == null) {
            return null;
        }

        byte[] instructionList = code.getCode();

        // Create callback
        UnpackedBytecodeCallback callback = new UnpackedBytecodeCallback(instructionList.length);

        // Scan the method.
        BytecodeScanner scanner = new BytecodeScanner();
        scanner.scan(instructionList, callback);

        return callback.getUnpackedCode();

    }
}
