/*
* FindBugs - Find bugs in Java programs
* Copyright (C) 2003-2005 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 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;
public class WaitInLoop extends BytecodeScanningDetector implements StatelessDetector {
boolean sawWait = false;
boolean sawAwait = false;
boolean waitHasTimeout = false;
boolean sawNotify = false;
int notifyPC;
int earliestJump = 0;
int waitAt = 0;
private final BugReporter bugReporter;
public WaitInLoop(BugReporter bugReporter) {
this.bugReporter = bugReporter;
}
@Override
public void visit(Code obj) {
sawWait = false;
sawAwait = false;
waitHasTimeout = false;
sawNotify = false;
earliestJump = 9999999;
super.visit(obj);
if ((sawWait || sawAwait) && waitAt < earliestJump) {
String bugType = sawWait ? "WA_NOT_IN_LOOP" : "WA_AWAIT_NOT_IN_LOOP";
bugReporter.reportBug(new BugInstance(this, bugType, waitHasTimeout ? LOW_PRIORITY : NORMAL_PRIORITY)
.addClassAndMethod(this).addSourceLine(this, waitAt));
}
if (sawNotify) {
bugReporter.reportBug(new BugInstance(this, "NO_NOTIFY_NOT_NOTIFYALL", LOW_PRIORITY).addClassAndMethod(this)
.addSourceLine(this, notifyPC));
}
}
@Override
public void sawOpcode(int seen) {
if ((seen == INVOKEVIRTUAL || seen == INVOKEINTERFACE) && getNameConstantOperand().equals("notify")
&& getSigConstantOperand().equals("()V")) {
sawNotify = true;
notifyPC = getPC();
}
if (!(sawWait || sawAwait) && (seen == INVOKEVIRTUAL || seen == INVOKEINTERFACE)
&& (isMonitorWait() || isConditionAwait())) {
if (getNameConstantOperand().equals("wait")) {
sawWait = true;
} else {
sawAwait = true;
}
waitHasTimeout = !getSigConstantOperand().equals("()V");
waitAt = getPC();
earliestJump = getPC() + 1;
return;
}
if (seen >= IFEQ && seen <= GOTO || seen >= IFNULL && seen <= GOTO_W) {
earliestJump = Math.min(earliestJump, getBranchTarget());
}
}
private boolean isConditionAwait() {
String className = getClassConstantOperand();
String name = getNameConstantOperand();
String sig = getSigConstantOperand();
if (!className.equals("java/util/concurrent/locks/Condition")) {
return false;
}
if (!name.startsWith("await")) {
return false;
}
if (name.equals("await") && (sig.equals("()V") || sig.equals("(JLjava/util/concurrent/TimeUnit;)V"))) {
return true;
}
if (name.equals("awaitNanos") && sig.equals("(J)V")) {
return true;
}
if (name.equals("awaitUninterruptibly") && sig.equals("()V")) {
return true;
}
if (name.equals("awaitUntil") && sig.equals("(Ljava/util/Date;)V")) {
return true;
}
return false;
}
private boolean isMonitorWait() {
String name = getNameConstantOperand();
String sig = getSigConstantOperand();
return name.equals("wait") && (sig.equals("()V") || sig.equals("(J)V") || sig.equals("(JI)V"));
}
}