/*
* FindBugs - Find bugs in Java programs
* Copyright (C) 2005 Dave Brosius <dbrosius@users.sourceforge.net>
* 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.detect;
import java.util.regex.Pattern;
import org.apache.bcel.classfile.Code;
import edu.umd.cs.findbugs.BugInstance;
import edu.umd.cs.findbugs.BugReporter;
import edu.umd.cs.findbugs.BytecodeScanningDetector;
import edu.umd.cs.findbugs.StatelessDetector;
import edu.umd.cs.findbugs.TypeAnnotation;
/* Look for sequences of the form:
* ICONST_1
ANEWARRAY int[]
DUP
ICONST_0
ALOAD 1: a
AASTORE
INVOKESTATIC Arrays.asList(Object[]) : List
*/
public class VarArgsProblems extends BytecodeScanningDetector implements StatelessDetector {
private final BugReporter bugReporter;
private int state;
public VarArgsProblems(BugReporter bugReporter) {
this.bugReporter = bugReporter;
}
@Override
public void visitCode(Code obj) {
state = SEEN_NOTHING;
super.visitCode(obj);
}
public static final int SEEN_NOTHING = 0;
public static final int SEEN_ICONST_1 = 1;
public static final int SEEN_ANEWARRAY = 2;
public static final int SEEN_DUP = 3;
public static final int SEEN_ICONST_0 = 4;
public static final int SEEN_ALOAD = 5;
public static final int SEEN_AASTORE = 6;
public static final int SEEN_GOTO = 7;
Pattern primitiveArray = Pattern.compile("\\[[IJDFSCB]");
String primitiveArraySig;
@Override
public void sawOpcode(int seen) {
// System.out.println("State:" + state);
if (seen == GOTO && getBranchOffset() == 4) {
state = SEEN_GOTO;
} else {
switch (state) {
case SEEN_NOTHING:
if ((seen == ICONST_1)) {
state = SEEN_ICONST_1;
}
break;
case SEEN_ICONST_1:
if (seen == ANEWARRAY && primitiveArray.matcher(getClassConstantOperand()).matches()) {
// System.out.println("Allocation of array of type " +
// getClassConstantOperand());
primitiveArraySig = getClassConstantOperand();
state = SEEN_ANEWARRAY;
} else {
state = SEEN_NOTHING;
}
break;
case SEEN_ANEWARRAY:
if (seen == DUP) {
state = SEEN_DUP;
} else {
state = SEEN_NOTHING;
}
break;
case SEEN_DUP:
if (seen == ICONST_0) {
state = SEEN_ICONST_0;
} else {
state = SEEN_NOTHING;
}
break;
case SEEN_ICONST_0:
if (((seen >= ALOAD_0) && (seen < ALOAD_3)) || (seen == ALOAD)) {
state = SEEN_ALOAD;
} else {
state = SEEN_NOTHING;
}
break;
case SEEN_ALOAD:
if (seen == AASTORE) {
state = SEEN_AASTORE;
} else {
state = SEEN_NOTHING;
}
break;
case SEEN_AASTORE:
if (seen == INVOKESTATIC || seen == INVOKEINTERFACE || seen == INVOKESPECIAL || seen == INVOKEVIRTUAL) {
// System.out.println(getClassConstantOperand());
// System.out.println(getNameConstantOperand());
// System.out.println(getSigConstantOperand());
if (getSigConstantOperand().indexOf("Ljava/lang/Object;)") == -1) {
break;
}
int priority = NORMAL_PRIORITY;
if (getNameConstantOperand().equals("asList") && getClassConstantOperand().equals("java/util/Arrays")) {
priority = HIGH_PRIORITY;
}
bugReporter.reportBug(new BugInstance(this, "VA_PRIMITIVE_ARRAY_PASSED_TO_OBJECT_VARARG", priority)
.addClassAndMethod(this).addType(primitiveArraySig).describe(TypeAnnotation.FOUND_ROLE)
.addCalledMethod(this).addSourceLine(this));
}
state = SEEN_NOTHING;
break;
case SEEN_GOTO:
state = SEEN_NOTHING;
break;
default:
throw new IllegalStateException("State " + state + " not expected");
}
}
}
}