/*
* Bytecode Analysis Framework
* Copyright (C) 2003,2004 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.ba;
import java.util.ArrayList;
import java.util.BitSet;
import java.util.List;
import java.util.StringTokenizer;
import org.apache.bcel.Constants;
import org.apache.bcel.classfile.ClassFormatException;
import org.apache.bcel.classfile.Constant;
import org.apache.bcel.classfile.ConstantMethodref;
import org.apache.bcel.classfile.ConstantNameAndType;
import org.apache.bcel.classfile.ConstantPool;
import org.apache.bcel.classfile.ConstantUtf8;
import org.apache.bcel.classfile.JavaClass;
import org.apache.bcel.generic.ConstantPoolGen;
import org.apache.bcel.generic.GETSTATIC;
import org.apache.bcel.generic.INVOKEINTERFACE;
import org.apache.bcel.generic.Instruction;
import org.apache.bcel.generic.InstructionHandle;
import org.apache.bcel.generic.InvokeInstruction;
import org.apache.bcel.generic.SIPUSH;
import edu.umd.cs.findbugs.SystemProperties;
/**
* Mark methodref constant pool entries of methods that are likely to implement
* assertions. This is useful for pruning likely false paths.
*
* @author David Hovemeyer
*/
public class AssertionMethods implements Constants {
private static final boolean DEBUG = SystemProperties.getBoolean("assertionmethods.debug");
/**
* Bitset of methodref constant pool indexes referring to likely assertion
* methods.
*/
private BitSet assertionMethodRefSet;
private static class UserAssertionMethod {
private String className;
private String methodName;
public UserAssertionMethod(String className, String methodName) {
this.className = className;
this.methodName = methodName;
}
public String getClassName() {
return className;
}
public String getMethodName() {
return methodName;
}
}
private static final List<UserAssertionMethod> userAssertionMethodList = new ArrayList<UserAssertionMethod>();
static {
String userProperty = SystemProperties.getProperty("findbugs.assertionmethods");
if (userProperty != null) {
StringTokenizer tok = new StringTokenizer(userProperty, ",");
while (tok.hasMoreTokens()) {
String fullyQualifiedName = tok.nextToken();
int lastDot = fullyQualifiedName.lastIndexOf('.');
if (lastDot < 0)
continue;
String className = fullyQualifiedName.substring(0, lastDot);
String methodName = fullyQualifiedName.substring(lastDot + 1);
userAssertionMethodList.add(new UserAssertionMethod(className, methodName));
}
}
}
/**
* Constructor.
*
* @param jclass
* the JavaClass containing the methodrefs
*/
public AssertionMethods(JavaClass jclass) {
this.assertionMethodRefSet = new BitSet();
init(jclass);
}
private void init(JavaClass jclass) {
ConstantPool cp = jclass.getConstantPool();
int numConstants = cp.getLength();
for (int i = 0; i < numConstants; ++i) {
try {
Constant c = cp.getConstant(i);
if (c instanceof ConstantMethodref) {
ConstantMethodref cmr = (ConstantMethodref) c;
ConstantNameAndType cnat = (ConstantNameAndType) cp.getConstant(cmr.getNameAndTypeIndex(),
CONSTANT_NameAndType);
String methodName = ((ConstantUtf8) cp.getConstant(cnat.getNameIndex(), CONSTANT_Utf8)).getBytes();
String className = cp.getConstantString(cmr.getClassIndex(), CONSTANT_Class).replace('/', '.');
String methodSig = ((ConstantUtf8) cp.getConstant(cnat.getSignatureIndex(), CONSTANT_Utf8)).getBytes();
String classNameLC = className.toLowerCase();
String methodNameLC = methodName.toLowerCase();
boolean voidReturnType = methodSig.endsWith(")V");
if (DEBUG) {
System.out.print("Is " + className + "." + methodName + " assertion method: " + voidReturnType);
}
if (isUserAssertionMethod(className, methodName)
|| className.endsWith("Assert")
&& methodName.startsWith("is")
|| voidReturnType
&& (classNameLC.indexOf("assert") >= 0 || methodNameLC.startsWith("throw")
|| methodName.startsWith("affirm") || methodName.startsWith("panic")
|| methodName.equals("logTerminal") || methodName.startsWith("logAndThrow")
|| methodNameLC.equals("insist") || methodNameLC.equals("usage")
|| methodNameLC.equals("exit") || methodNameLC.startsWith("fail")
|| methodNameLC.startsWith("fatal") || methodNameLC.indexOf("assert") >= 0
|| methodNameLC.indexOf("legal") >= 0 || methodNameLC.indexOf("error") >= 0
|| methodNameLC.indexOf("abort") >= 0
// || methodNameLC.indexOf("check") >= 0
|| methodNameLC.indexOf("failed") >= 0) || methodName.equals("addOrThrowException")) {
assertionMethodRefSet.set(i);
if (DEBUG) {
System.out.println("==> YES");
}
} else {
if (DEBUG) {
System.out.println("==> NO");
}
}
}
} catch (ClassFormatException e) {
// FIXME: should report
}
}
}
private static boolean isUserAssertionMethod(String className, String methodName) {
for (UserAssertionMethod uam : userAssertionMethodList) {
if (className.equals(uam.getClassName()) && methodName.equals(uam.getMethodName()))
return true;
}
return false;
}
public boolean isAssertionHandle(InstructionHandle handle, ConstantPoolGen cpg) {
Instruction ins = handle.getInstruction();
if (isAssertionInstruction(ins, cpg))
return true;
if (ins instanceof SIPUSH) {
int v = ((SIPUSH) ins).getValue().intValue();
if (v == 500) {
Instruction next = handle.getNext().getInstruction();
if (next instanceof INVOKEINTERFACE) {
INVOKEINTERFACE iInterface = (INVOKEINTERFACE) next;
String className = iInterface.getClassName(cpg);
String fieldName = iInterface.getMethodName(cpg);
if (className.equals("javax.servlet.http.HttpServletResponse") && fieldName.equals("setStatus"))
return true;
}
}
}
return false;
}
/**
* Does the given instruction refer to a likely assertion method?
*
* @param ins
* the instruction
* @return true if the instruction likely refers to an assertion, false if
* not
*/
public boolean isAssertionInstruction(Instruction ins, ConstantPoolGen cpg) {
if (ins instanceof InvokeInstruction)
return isAssertionCall((InvokeInstruction) ins);
if (ins instanceof GETSTATIC) {
GETSTATIC getStatic = (GETSTATIC) ins;
String className = getStatic.getClassName(cpg);
String fieldName = getStatic.getFieldName(cpg);
if (className.equals("java.util.logging.Level") && fieldName.equals("SEVERE"))
return true;
if (className.equals("org.apache.log4j.Level") && (fieldName.equals("ERROR") || fieldName.equals("FATAL")))
return true;
return false;
}
return false;
}
public boolean isAssertionCall(InvokeInstruction inv) {
if (DEBUG) {
System.out.print("Checking if " + inv + " is an assertion method: ");
}
boolean isAssertionMethod = assertionMethodRefSet.get(inv.getIndex());
if (DEBUG) {
System.out.println("==> " + isAssertionMethod);
}
return isAssertionMethod;
}
}
// vim:ts=4