/*
* FindBugs - Find bugs in Java programs
* Copyright (C) 2004-2006 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.HashSet;
import javax.annotation.CheckForNull;
import org.apache.bcel.classfile.Code;
import org.apache.bcel.classfile.Field;
import org.apache.bcel.classfile.JavaClass;
import org.apache.bcel.generic.Type;
import edu.umd.cs.findbugs.BugInstance;
import edu.umd.cs.findbugs.BugReporter;
import edu.umd.cs.findbugs.FirstPassDetector;
import edu.umd.cs.findbugs.OpcodeStack;
import edu.umd.cs.findbugs.OpcodeStack.Item;
import edu.umd.cs.findbugs.SystemProperties;
import edu.umd.cs.findbugs.ba.AnalysisContext;
import edu.umd.cs.findbugs.ba.SignatureParser;
import edu.umd.cs.findbugs.ba.XFactory;
import edu.umd.cs.findbugs.ba.XMethod;
import edu.umd.cs.findbugs.ba.generic.GenericObjectType;
import edu.umd.cs.findbugs.ba.generic.GenericSignatureParser;
import edu.umd.cs.findbugs.ba.generic.GenericUtilities;
import edu.umd.cs.findbugs.bcel.BCELUtil;
import edu.umd.cs.findbugs.bcel.OpcodeStackDetector;
import edu.umd.cs.findbugs.internalAnnotations.SlashedClassName;
import edu.umd.cs.findbugs.util.ClassName;
public class FunctionsThatMightBeMistakenForProcedures extends OpcodeStackDetector implements FirstPassDetector {
final BugReporter bugReporter;
final static boolean REPORT_INFERRED_METHODS = SystemProperties.getBoolean("mrc.inferred.report");
public FunctionsThatMightBeMistakenForProcedures(BugReporter bugReporter) {
this.bugReporter = bugReporter;
setVisitMethodsInCallOrder(true);
}
boolean isInnerClass, hasNonFinalFields;
@Override
public void visit(JavaClass obj) {
isInnerClass = false;
hasNonFinalFields = false;
}
@Override
public void visit(Field obj) {
if (obj.getName().equals("this$0"))
isInnerClass = true;
if (!obj.isFinal() && !obj.isStatic() && !BCELUtil.isSynthetic(obj))
hasNonFinalFields = true;
}
@Override
public void visitAfter(JavaClass obj) {
okToIgnore.clear();
doNotIgnore.clear();
doNotIgnoreHigh.clear();
methodsSeen.clear();
}
HashSet<XMethod> okToIgnore = new HashSet<XMethod>();
HashSet<XMethod> methodsSeen = new HashSet<XMethod>();
HashSet<XMethod> doNotIgnore = new HashSet<XMethod>();
HashSet<XMethod> doNotIgnoreHigh = new HashSet<XMethod>();
int returnSelf, returnOther, returnNew, returnUnknown;
int updates;
@CheckForNull BugInstance inferredMethod;
@Override
public void visit(Code code) {
methodsSeen.add(getXMethod());
String signature = getMethodSig();
SignatureParser parser = new SignatureParser(signature);
String returnType = parser.getReturnTypeSignature();
@SlashedClassName
String r = ClassName.fromFieldSignature(returnType);
if (r == null || !r.equals(getClassName()))
return;
// System.out.println("Checking " + getFullyQualifiedMethodName());
boolean funky = false;
for (int i = 0; i < parser.getNumParameters(); i++) {
String p = ClassName.fromFieldSignature(parser.getParameter(i));
if (getClassName().equals(p)) {
funky = true;
}
}
//
XMethod m = getXMethod();
String sourceSig = m.getSourceSignature();
if (sourceSig != null) {
GenericSignatureParser sig = new GenericSignatureParser(sourceSig);
String genericReturnValue = sig.getReturnTypeSignature();
Type t = GenericUtilities.getType(genericReturnValue);
if (t instanceof GenericObjectType) {
funky = true;
}
// if (false) {
// XClass c = getXClass();
// String classSourceSig = c.getSourceSignature();
// if (!genericReturnValue.equals(classSourceSig))
// return;
// }
}
// System.out.println("Investigating " + getFullyQualifiedMethodName());
returnSelf = returnOther = updates = returnNew = returnUnknown = 0;
if (REPORT_INFERRED_METHODS
&& AnalysisContext.currentAnalysisContext().isApplicationClass(getThisClass()))
inferredMethod = new BugInstance("TESTING", NORMAL_PRIORITY).addClassAndMethod(this);
else
inferredMethod = null;
super.visit(code); // make callbacks to sawOpcode for all opcodes
// System.out.printf(" %3d %3d %3d %3d%n", returnSelf, updates, returnOther, returnNew);
if (returnSelf > 0 && returnOther == 0) {
okToIgnore.add(m);
} else if (funky) {
okToIgnore.add(m);
} else if (returnOther > 0 && returnOther >= returnSelf && returnNew > 0 && returnNew >= returnOther - 1) {
int priority = HIGH_PRIORITY;
if (returnSelf > 0 || updates > 0)
priority++;
if (returnUnknown > 0)
priority++;
if (returnNew > 0 && priority > NORMAL_PRIORITY)
priority = NORMAL_PRIORITY;
if (updates > 0)
priority = LOW_PRIORITY;
if (priority <= HIGH_PRIORITY)
doNotIgnoreHigh.add(m);
if (priority <= NORMAL_PRIORITY) {
// System.out.printf(" adding %d %s%n", priority,
// MethodAnnotation.fromVisitedMethod(this).getSourceLines());
doNotIgnore.add(m);
if (!m.isStatic()) {
XFactory xFactory = AnalysisContext.currentXFactory();
xFactory.addFunctionThatMightBeMistakenForProcedures(getMethodDescriptor());
if (inferredMethod != null) {
inferredMethod.setPriority(priority);
inferredMethod.addString(String.format("%3d %3d %5d %3d", returnOther, returnSelf, returnNew, updates));
bugReporter.reportBug(inferredMethod);
}
}
}
inferredMethod = null;
}
}
@Override
public void sawOpcode(int seen) {
switch (seen) {
case INVOKEVIRTUAL:
case INVOKESPECIAL: {
if (getMethod().isStatic() || !hasNonFinalFields)
break;
String name = getNameConstantOperand();
String sig = getSigConstantOperand();
if ((name.startsWith("set") || name.startsWith("update")) || sig.endsWith(")V")) {
Item invokedOn = stack.getItemMethodInvokedOn(this);
if (invokedOn.isInitialParameter() && invokedOn.getRegisterNumber() == 0)
updates++;
if (inferredMethod != null)
inferredMethod.addCalledMethod(this);
}
break;
}
case ARETURN: {
OpcodeStack.Item rv = stack.getStackItem(0);
if (rv.isNull())
break;
if (rv.isInitialParameter()) {
returnSelf++;
break;
}
XMethod xMethod = rv.getReturnValueOf();
if (xMethod == null) {
returnSelf++;
break;
}
if (inferredMethod != null)
inferredMethod.addCalledMethod(xMethod);
if (okToIgnore.contains(xMethod) ) {
returnSelf++;
break;
}
if (xMethod.getName().equals("<init>")) {
String sig = xMethod.getSignature();
// returning a newly constructed value
boolean voidConstructor;
if (!isInnerClass) {
voidConstructor = sig.equals("()V");
} else {
SignatureParser parser = new SignatureParser(sig);
voidConstructor = parser.getNumParameters() <= 1;
}
if (voidConstructor) {
returnSelf++;
} else {
returnOther++;
returnNew++;
}
break;
}
if (xMethod.isAbstract() && !xMethod.getClassDescriptor().equals(getClassDescriptor())) {
returnUnknown++;
break;
}
if (xMethod.getName().equals("<init>") || doNotIgnoreHigh.contains(xMethod)) {
returnOther++;
// System.out.println(" calls " + xMethod);
// System.out.println(" at " +
// MethodAnnotation.fromXMethod(xMethod).getSourceLines());
if (xMethod.getName().equals("<init>") || doNotIgnore.contains(xMethod))
returnNew++;
} else if (doNotIgnore.contains(xMethod)) {
returnOther++;
// System.out.println(" calls " + xMethod);
// System.out.println(" at " +
// MethodAnnotation.fromXMethod(xMethod).getSourceLines());
} else
returnUnknown++;
}
break;
case PUTFIELD: {
OpcodeStack.Item rv = stack.getStackItem(1);
if (rv.getRegisterNumber() == 0 && rv.isInitialParameter()) {
if (inferredMethod != null)
inferredMethod.addReferencedField(this);
updates++;
}
}
}
}
}