volatileusage.java

来自「A static analysis tool to find bugs in J」· Java 代码 · 共 113 行

/*
 * 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 edu.umd.cs.findbugs.*;
import edu.umd.cs.findbugs.ba.ClassContext;
import java.util.*;
import org.apache.bcel.classfile.Field;

public class VolatileUsage extends BytecodeScanningDetector  {
	  private BugReporter bugReporter;

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

	@Override
		 public void visitClassContext(ClassContext classContext) {
				classContext.getJavaClass().accept(this);
	}

static class FieldRecord {
				String className;
				String name;
				String signature;
				boolean isStatic;
		}


	Map<String,FieldRecord> fieldInfo = new HashMap<String,FieldRecord>();
	Set<String> initializationWrites = new HashSet<String>();
	Set<String> otherWrites = new HashSet<String>();


	@Override
		 public void visit(Field obj) {
		super.visit(obj);
		int flags = obj.getAccessFlags();
		if ((flags & ACC_VOLATILE) == 0) return;
		if (getFieldSig().charAt(0) == '[') {
		   FieldRecord f = new FieldRecord();
			f.className = getDottedClassName();
			f.name = getFieldName();
			f.signature = getFieldSig();
			f.isStatic = !((flags & ACC_STATIC) == 0);
			fieldInfo.put(getDottedClassName() + "." + getFieldName(),
					f);
		}
	}

	@Override
	public void sawOpcode(int seen) {
				switch (seen) {
				case PUTSTATIC:
			{
						String name = (getClassConstantOperand() 
					+ "." + getNameConstantOperand())
								.replace('/', '.');
			if (getMethodName().equals("<clinit>"))
				initializationWrites.add(name);
			else otherWrites.add(name);
			break;
			}
				case PUTFIELD:
						{
			String name = (getClassConstantOperand() 
					+ "." + getNameConstantOperand())
								.replace('/', '.');
			if (getMethodName().equals("<init>"))
				initializationWrites.add(name);
			else otherWrites.add(name);
			break;
			}
		}
		}


	@Override
		 public void report() {

		for(Map.Entry<String, FieldRecord> r : fieldInfo.entrySet()) {	
		   String name = r.getKey();
		   FieldRecord f = r.getValue();
		   int priority = LOW_PRIORITY;
		   if (initializationWrites.contains(name) 
			&& !otherWrites.contains(name))
			 priority = NORMAL_PRIORITY;
		   bugReporter.reportBug(
			new BugInstance(this, "VO_VOLATILE_REFERENCE_TO_ARRAY", priority)
			 .addClass(f.className)
			 .addField(f.className, f.name, f.signature, f.isStatic));
		}
		}
}