/*
 * FindBugs - Find Bugs in Java programs
 * 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.Method;
import org.apache.bcel.generic.MethodGen;

import edu.umd.cs.findbugs.ba.AnalysisContext;
import edu.umd.cs.findbugs.ba.AnalysisFeatures;
import edu.umd.cs.findbugs.ba.CFG;
import edu.umd.cs.findbugs.ba.ClassContext;
import edu.umd.cs.findbugs.ba.DepthFirstSearch;
import edu.umd.cs.findbugs.ba.MethodUnprofitableException;
import edu.umd.cs.findbugs.ba.type.ExceptionSetFactory;
import edu.umd.cs.findbugs.ba.type.TypeAnalysis;
import edu.umd.cs.findbugs.ba.type.TypeDataflow;
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 TypeDataflow objects for analyzed methods.
 * 
 * @author David Hovemeyer
 */
public class TypeDataflowFactory extends AnalysisFactory<TypeDataflow> {
    /**
     * Constructor.
     */
    public TypeDataflowFactory() {
        super("type analysis", TypeDataflow.class);
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * edu.umd.cs.findbugs.classfile.IAnalysisEngine#analyze(edu.umd.cs.findbugs
     * .classfile.IAnalysisCache, java.lang.Object)
     */
    public TypeDataflow analyze(IAnalysisCache analysisCache, MethodDescriptor descriptor) throws CheckedAnalysisException {
        MethodGen methodGen = getMethodGen(analysisCache, descriptor);
        if (methodGen == null) {
            throw new MethodUnprofitableException(descriptor);
        }
        CFG cfg = getCFG(analysisCache, descriptor);
        DepthFirstSearch dfs = getDepthFirstSearch(analysisCache, descriptor);
        ExceptionSetFactory exceptionSetFactory = getExceptionSetFactory(analysisCache, descriptor);
        Method method = getMethod(analysisCache, descriptor);

        TypeAnalysis typeAnalysis = new TypeAnalysis(method, methodGen, cfg, dfs, AnalysisContext.currentAnalysisContext()
                .getLookupFailureCallback(), exceptionSetFactory);

        if (AnalysisContext.currentAnalysisContext().getBoolProperty(AnalysisFeatures.MODEL_INSTANCEOF)) {
            typeAnalysis.setValueNumberDataflow(getValueNumberDataflow(analysisCache, descriptor));
        }

        // Field store type database.
        // If present, this can give us more accurate type information
        // for values loaded from fields.
        typeAnalysis.setFieldStoreTypeDatabase(AnalysisContext.currentAnalysisContext().getFieldStoreTypeDatabase());

        TypeDataflow typeDataflow = new TypeDataflow(cfg, typeAnalysis);
        try {
            typeDataflow.execute();
        } catch (CheckedAnalysisException e) {
            AnalysisContext.logError("Error performing type dataflow analysis of " + descriptor, e);
            throw e;
        }
        if (TypeAnalysis.DEBUG || ClassContext.DUMP_DATAFLOW_ANALYSIS) {
            ClassContext.dumpTypeDataflow(method, cfg, typeDataflow);
        }

        return typeDataflow;
    }
}
