/* * 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.BitSet; import java.util.HashSet; import java.util.Iterator; import java.util.concurrent.ConcurrentMap; import org.apache.bcel.Constants; import org.apache.bcel.classfile.Constant; import org.apache.bcel.classfile.ConstantNameAndType; import org.apache.bcel.classfile.ConstantPool; import org.apache.bcel.classfile.JavaClass; import org.apache.bcel.classfile.Method; import org.apache.bcel.generic.ArrayType; import org.apache.bcel.generic.ConstantPoolGen; import org.apache.bcel.generic.IFNONNULL; import org.apache.bcel.generic.IFNULL; import org.apache.bcel.generic.INVOKESTATIC; import org.apache.bcel.generic.Instruction; import org.apache.bcel.generic.InstructionHandle; import org.apache.bcel.generic.InvokeInstruction; import org.apache.bcel.generic.MethodGen; import org.apache.bcel.generic.ObjectType; import org.apache.bcel.generic.POP; import org.apache.bcel.generic.Type; import edu.umd.cs.findbugs.BugAccumulator; import edu.umd.cs.findbugs.BugAnnotation; import edu.umd.cs.findbugs.BugInstance; import edu.umd.cs.findbugs.BugReporter; import edu.umd.cs.findbugs.Detector; import edu.umd.cs.findbugs.SourceLineAnnotation; import edu.umd.cs.findbugs.SystemProperties; import edu.umd.cs.findbugs.TypeAnnotation; import edu.umd.cs.findbugs.ba.AnalysisContext; import edu.umd.cs.findbugs.ba.CFG; import edu.umd.cs.findbugs.ba.CFGBuilderException; import edu.umd.cs.findbugs.ba.ClassContext; import edu.umd.cs.findbugs.ba.Dataflow; import edu.umd.cs.findbugs.ba.DataflowAnalysisException; import edu.umd.cs.findbugs.ba.LiveLocalStoreAnalysis; import edu.umd.cs.findbugs.ba.Location; import edu.umd.cs.findbugs.ba.XClass; import edu.umd.cs.findbugs.ba.XField; import edu.umd.cs.findbugs.ba.ch.Subtypes2; import edu.umd.cs.findbugs.ba.type.TypeDataflow; import edu.umd.cs.findbugs.ba.vna.ValueNumber; import edu.umd.cs.findbugs.ba.vna.ValueNumberDataflow; import edu.umd.cs.findbugs.ba.vna.ValueNumberFrame; import edu.umd.cs.findbugs.ba.vna.ValueNumberSourceInfo; import edu.umd.cs.findbugs.classfile.ClassDescriptor; import edu.umd.cs.findbugs.classfile.DescriptorFactory; import edu.umd.cs.findbugs.core.Priorities; import edu.umd.cs.findbugs.internalAnnotations.DottedClassName; import edu.umd.cs.findbugs.internalAnnotations.SlashedClassName; public class DontIgnoreResultOfPutIfAbsent implements Detector { final static boolean countOtherCalls = false; final BugReporter bugReporter; final BugAccumulator accumulator; final ClassDescriptor concurrentMapDescriptor = DescriptorFactory.createClassDescriptor(ConcurrentMap.class); public DontIgnoreResultOfPutIfAbsent(BugReporter bugReporter) { this.bugReporter = bugReporter; this.accumulator = new BugAccumulator(bugReporter); } /* * (non-Javadoc) * * @see edu.umd.cs.findbugs.Detector#report() */ public void report() { // TODO Auto-generated method stub } public void visitClassContext(ClassContext classContext) { JavaClass javaClass = classContext.getJavaClass(); ConstantPool pool = javaClass.getConstantPool(); boolean found = false; for (Constant constantEntry : pool.getConstantPool()) if (constantEntry instanceof ConstantNameAndType) { ConstantNameAndType nt = (ConstantNameAndType) constantEntry; if (nt.getName(pool).equals("putIfAbsent")) { found = true; break; } } if (!found) return; Method[] methodList = javaClass.getMethods(); for (Method method : methodList) { MethodGen methodGen = classContext.getMethodGen(method); if (methodGen == null) continue; try { analyzeMethod(classContext, method); } catch (DataflowAnalysisException e) { bugReporter.logError("Error analyzing " + method.toString(), e); } catch (CFGBuilderException e) { bugReporter.logError("Error analyzing " + method.toString(), e); } } } final static boolean DEBUG = false; static HashSet<String> immutableClassNames = new HashSet<String>(); static { immutableClassNames.add("java/lang/Integer"); immutableClassNames.add("java/lang/Long"); immutableClassNames.add("java/lang/String"); immutableClassNames.add("java/util/Comparator"); } private static int getPriorityForBeingMutable(Type type) { if (type instanceof ArrayType) { return HIGH_PRIORITY; } else if (type instanceof ObjectType) { UnreadFieldsData unreadFields = AnalysisContext.currentAnalysisContext().getUnreadFieldsData(); ClassDescriptor cd = DescriptorFactory.getClassDescriptor((ObjectType) type); @SlashedClassName String className = cd.getClassName(); if (immutableClassNames.contains(className)) return Priorities.LOW_PRIORITY; XClass xClass = AnalysisContext.currentXFactory().getXClass(cd); if (xClass == null) return Priorities.IGNORE_PRIORITY; ClassDescriptor superclassDescriptor = xClass.getSuperclassDescriptor(); if (superclassDescriptor != null) { @SlashedClassName String superClassName = superclassDescriptor.getClassName(); if (superClassName.equals("java/lang/Enum")) return Priorities.LOW_PRIORITY; } boolean hasMutableField = false; boolean hasUpdates = false; for (XField f : xClass.getXFields()) if (!f.isStatic()) { if (!f.isFinal() && !f.isSynthetic()) { hasMutableField = true; if (unreadFields.isWrittenOutsideOfInitialization(f)) hasUpdates = true; } String signature = f.getSignature(); if (signature.startsWith("Ljava/util/concurrent") || signature.startsWith("Ljava/lang/StringB") || signature.charAt(0) == '[' || signature.indexOf("Map") >= 0 || signature.indexOf("List") >= 0 || signature.indexOf("Set") >= 0) hasMutableField = hasUpdates = true; } if (!hasMutableField && !xClass.isInterface() && !xClass.isAbstract()) return Priorities.LOW_PRIORITY; if (hasUpdates || className.startsWith("java/util") || className.indexOf("Map") >= 0 || className.indexOf("List") >= 0) return Priorities.HIGH_PRIORITY; return Priorities.NORMAL_PRIORITY; } else return Priorities.IGNORE_PRIORITY; } private void analyzeMethod(ClassContext classContext, Method method) throws DataflowAnalysisException, CFGBuilderException { if (method.isSynthetic() || (method.getAccessFlags() & Constants.ACC_BRIDGE) == Constants.ACC_BRIDGE) return; if (DEBUG) { System.out.println(" Analyzing method " + classContext.getJavaClass().getClassName() + "." + method.getName()); } JavaClass javaClass = classContext.getJavaClass(); ConstantPoolGen cpg = classContext.getConstantPoolGen(); Dataflow<BitSet, LiveLocalStoreAnalysis> llsaDataflow = classContext.getLiveLocalStoreDataflow(method); MethodGen methodGen = classContext.getMethodGen(method); CFG cfg = classContext.getCFG(method); ValueNumberDataflow vnaDataflow = classContext.getValueNumberDataflow(method); TypeDataflow typeDataflow = classContext.getTypeDataflow(method); String sourceFileName = javaClass.getSourceFileName(); for (Iterator<Location> i = cfg.locationIterator(); i.hasNext();) { Location location = i.next(); InstructionHandle handle = location.getHandle(); Instruction ins = handle.getInstruction(); if (ins instanceof InvokeInstruction) { InvokeInstruction invoke = (InvokeInstruction) ins; String className = invoke.getClassName(cpg); if (invoke.getMethodName(cpg).equals("putIfAbsent")) { String signature = invoke.getSignature(cpg); if (signature.equals("(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;") && !(invoke instanceof INVOKESTATIC) && extendsConcurrentMap(className)) { InstructionHandle next = handle.getNext(); boolean isIgnored = next != null && next.getInstruction() instanceof POP; boolean isImmediateNullTest = next != null && (next.getInstruction() instanceof IFNULL || next.getInstruction() instanceof IFNONNULL); if (countOtherCalls || isIgnored) { BitSet live = llsaDataflow.getAnalysis().getFactAtLocation(location); ValueNumberFrame vna = vnaDataflow.getAnalysis().getFactAtLocation(location); ValueNumber vn = vna.getTopValue(); int locals = vna.getNumLocals(); boolean isRetained = false; for (int pos = 0; pos < locals; pos++) if (vna.getValue(pos).equals(vn) && live.get(pos)) { BugAnnotation ba = ValueNumberSourceInfo.findAnnotationFromValueNumber(method, location, vn, vnaDataflow.getFactAtLocation(location), "VALUE_OF"); if (ba == null) continue; String pattern = "RV_RETURN_VALUE_OF_PUTIFABSENT_IGNORED"; if (!isIgnored) pattern = "UNKNOWN"; Type type = typeDataflow.getAnalysis().getFactAtLocation(location).getTopValue(); int priority = getPriorityForBeingMutable(type); BugInstance bugInstance = new BugInstance(this, pattern, priority) .addClassAndMethod(methodGen, sourceFileName).addCalledMethod(methodGen, invoke) .add(new TypeAnnotation(type)).add(ba); SourceLineAnnotation where = SourceLineAnnotation.fromVisitedInstruction(classContext, method, location); accumulator.accumulateBug(bugInstance, where); isRetained = true; break; } if (countOtherCalls && !isRetained && SystemProperties.getBoolean("report_TESTING_pattern_in_standard_detectors")) { int priority = LOW_PRIORITY; if (!isImmediateNullTest && !isIgnored) { TypeDataflow typeAnalysis = classContext.getTypeDataflow(method); Type type = typeAnalysis.getFactAtLocation(location).getTopValue(); String valueSignature = type.getSignature(); if (!valueSignature.startsWith("Ljava/util/concurrent/atomic/Atomic")) priority = Priorities.HIGH_PRIORITY; } BugInstance bugInstance = new BugInstance(this, "TESTING", priority) .addClassAndMethod(methodGen, sourceFileName).addString("Counting putIfAbsentCalls") .addCalledMethod(methodGen, invoke); SourceLineAnnotation where = SourceLineAnnotation.fromVisitedInstruction(classContext, method, location); accumulator.accumulateBug(bugInstance, where); } } } else if (countOtherCalls) { BugInstance bugInstance = new BugInstance(this, "TESTING2", Priorities.NORMAL_PRIORITY) .addClassAndMethod(methodGen, sourceFileName).addCalledMethod(methodGen, invoke); SourceLineAnnotation where = SourceLineAnnotation.fromVisitedInstruction(classContext, method, location); accumulator.accumulateBug(bugInstance, where); } } } } accumulator.reportAccumulatedBugs(); } private boolean extendsConcurrentMap(@DottedClassName String className) { if (className.equals("java.util.concurrent.ConcurrentHashMap") || className.equals(concurrentMapDescriptor.getDottedClassName())) return true; ClassDescriptor c = DescriptorFactory.createClassDescriptorFromDottedClassName(className); Subtypes2 subtypes2 = AnalysisContext.currentAnalysisContext().getSubtypes2(); try { if (subtypes2.isSubtype(c, concurrentMapDescriptor)) return true; } catch (ClassNotFoundException e) { AnalysisContext.reportMissingClass(e); } return false; } }