/*
* Bytecode analysis framework
* Copyright (C) 2005, 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.ba.type;
import java.util.HashSet;
import java.util.Iterator;
import org.apache.bcel.classfile.ClassFormatException;
import org.apache.bcel.generic.ReferenceType;
import org.apache.bcel.generic.Type;
import edu.umd.cs.findbugs.ba.AnalysisContext;
import edu.umd.cs.findbugs.ba.Hierarchy;
import edu.umd.cs.findbugs.ba.ch.Subtypes2;
/**
* Field property storing the types of values stored in a field. The idea is
* that we may be able to determine a more precise type for values loaded from
* the field than the field type alone would indicate.
*
* @author David Hovemeyer
*/
public class FieldStoreType {
private final HashSet<String> typeSignatureSet;
private ReferenceType loadType;
public FieldStoreType() {
this.typeSignatureSet = new HashSet<String>();
}
// TODO: type may be exact
public void addTypeSignature(String signature) {
loadType = null;
typeSignatureSet.add(signature);
}
public Iterator<String> signatureIterator() {
return typeSignatureSet.iterator();
}
public ReferenceType getLoadType(ReferenceType fieldType) {
if (loadType == null) {
computeLoadType(fieldType);
}
return loadType;
}
private void computeLoadType(ReferenceType fieldType) {
ReferenceType leastSupertype = null;
for (Iterator<String> i = signatureIterator(); i.hasNext();) {
try {
String signature = i.next();
Type type = Type.getType(signature);
if (!(type instanceof ReferenceType)) {
continue;
}
// FIXME: this will mangle interface types, since
// getFirstCommonSuperclass() ignores interfaces.
/*
* leastSupertype = (leastSupertype == null) ? (ReferenceType)
* type :
* leastSupertype.getFirstCommonSuperclass((ReferenceType)
* type);
*/
if (leastSupertype == null) {
leastSupertype = (ReferenceType) type;
} else {
if (Subtypes2.ENABLE_SUBTYPES2_FOR_COMMON_SUPERCLASS_QUERIES) {
leastSupertype = AnalysisContext.currentAnalysisContext().getSubtypes2()
.getFirstCommonSuperclass(leastSupertype, (ReferenceType) type);
} else {
leastSupertype = leastSupertype.getFirstCommonSuperclass((ReferenceType) type);
}
}
} catch (ClassFormatException e) {
// Bad signature: ignore
} catch (ClassNotFoundException e) {
AnalysisContext.reportMissingClass(e);
}
}
try {
if (leastSupertype != null && Hierarchy.isSubtype(leastSupertype, fieldType)) {
loadType = leastSupertype;
}
} catch (ClassNotFoundException e) {
AnalysisContext.reportMissingClass(e);
}
if (loadType == null) {
loadType = fieldType;
}
}
}