/*
 * FindBugs - Find bugs in Java programs
 * Copyright (C) 2004, 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.detect;

import org.apache.bcel.generic.ConstantPoolGen;
import org.apache.bcel.generic.Instruction;
import org.apache.bcel.generic.InvokeInstruction;
import org.apache.bcel.generic.ObjectType;

import edu.umd.cs.findbugs.ba.Hierarchy;
import edu.umd.cs.findbugs.ba.Location;
import edu.umd.cs.findbugs.ba.ObjectTypeFactory;
import edu.umd.cs.findbugs.ba.RepositoryLookupFailureCallback;

/**
 * Factory for stream objects of a particular base class type returned by any
 * method. This factory helps us keep track of streams returned by methods; we
 * don't want to report them, but we do want to keep track of whether or not
 * they are closed, to avoid reporting unclosed streams in the same equivalence
 * class.
 */
public class AnyMethodReturnValueStreamFactory implements StreamFactory {
    private final ObjectType baseClassType;

    private String bugType;

    public AnyMethodReturnValueStreamFactory(String streamBase) {
        this.baseClassType = ObjectTypeFactory.getInstance(streamBase);
        this.bugType = null;
    }

    public AnyMethodReturnValueStreamFactory setBugType(String bugType) {
        this.bugType = bugType;
        return this;
    }

    @Override
    public Stream createStream(Location location, ObjectType type, ConstantPoolGen cpg,
            RepositoryLookupFailureCallback lookupFailureCallback) {

        Instruction ins = location.getHandle().getInstruction();

        try {
            if (ins instanceof InvokeInstruction) {
                if (!Hierarchy.isSubtype(type, baseClassType)) {
                    return null;
                }

                Stream stream = new Stream(location, type.getClassName(), baseClassType.getClassName()).setIsOpenOnCreation(true)
                        .setIgnoreImplicitExceptions(true);
                if (bugType != null) {
                    stream.setInteresting(bugType);
                }

                return stream;
            }
        } catch (ClassNotFoundException e) {
            lookupFailureCallback.reportMissingClass(e);
        }

        return null;
    }
}

