/*
 * FindBugs - Find bugs in Java programs
 * Copyright (C) 2003, 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;
import org.apache.bcel.classfile.Code;
import org.apache.bcel.classfile.Method;
import edu.umd.cs.pugh.visitclass.Constants2;

//   2:   astore_1
//   3:   monitorenter
//   4:   aload_0
//   5:   invokevirtual   #13; //Method java/lang/Object.notify:()V
//   8:   aload_1
//   9:   monitorexit


public class FindNakedNotify extends BytecodeScanningDetector implements   Constants2 {
    int stage = 0;
    private BugReporter bugReporter;
    boolean synchronizedMethod;

    public FindNakedNotify(BugReporter bugReporter) {
	this.bugReporter = bugReporter;
	}

    public void visit(Method obj) {
	int flags = obj.getAccessFlags();
	synchronizedMethod = (flags & ACC_SYNCHRONIZED) != 0;
	}

    public void visit(Code obj) {
	stage = synchronizedMethod ? 1 : 0;
	super.visit(obj);
	if (synchronizedMethod && stage == 4) 
		bugReporter.reportBug(
			new BugInstance("NN_NAKED_NOTIFY", NORMAL_PRIORITY)
			.addClassAndMethod(this));
	}

    public void sawOpcode(int seen) {
	switch (stage) {
		case 0:
			if (seen == MONITORENTER) 
				stage = 1;		
			break;
		case 1:
			stage = 2;
			break;
		case 2:
			if (seen == INVOKEVIRTUAL 
				&& (nameConstant.equals("notify")
				   || nameConstant.equals("notifyAll"))
				&& sigConstant.equals("()V"))
			  stage = 3;
			else stage = 0;
			break;
		case 3:
			stage = 4;
			break;
		case 4:
			if (seen == MONITOREXIT) {
				bugReporter.reportBug(new BugInstance("NN_NAKED_NOTIFY", NORMAL_PRIORITY)
					.addClassAndMethod(this));
				stage = 5;
				}
			else
				stage = 0;
			break; 
		case 5:
			}
		
	}
}

@@ -1331,16 +1331,42 @@
 dMethod;
+%0A    private int notifyPC;
 %0A%0A    pu
@@ -1813,24 +1813,58 @@
 Method(this)
+%0A%09%09%09.addSourceLine(this, notifyPC)
 );%0A%09%7D%0A%0A    p
@@ -2170,16 +2170,18 @@
 (%22()V%22))
+ %7B
 %0A%09%09%09  st
@@ -2189,16 +2189,43 @@
 ge = 3;%0A
+%09%09%09  notifyPC = PC;%0A%09%09%09  %7D%0A
 %09%09%09else 
@@ -2426,16 +2426,52 @@
 od(this)
+%0A%09%09%09%09%09.addSourceLine(this, notifyPC)
 );%0A%09%09%09%09s

Add source line annotation for notify call.