FindUnsyncGet.java

/*
 * FindBugs - Find bugs in Java programs
 * 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.detect;

import java.util.HashMap;
import java.util.HashSet;
import java.util.Set;

import org.apache.bcel.classfile.JavaClass;
import org.apache.bcel.classfile.Method;

import edu.umd.cs.findbugs.BugInstance;
import edu.umd.cs.findbugs.BugReporter;
import edu.umd.cs.findbugs.BytecodeScanningDetector;
import edu.umd.cs.findbugs.MethodAnnotation;

public class FindUnsyncGet extends BytecodeScanningDetector {
    String prevClassName = " none ";

    private BugReporter bugReporter;

    static final int doNotConsider = ACC_PRIVATE | ACC_STATIC | ACC_NATIVE;

    // Maps of property names to get and set methods
    private HashMap<String, MethodAnnotation> getMethods = new HashMap<String, MethodAnnotation>();

    private HashMap<String, MethodAnnotation> setMethods = new HashMap<String, MethodAnnotation>();

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

    @Override
    public void report() {
        // Find the set of properties for which we have both
        // unsynchronized get and synchronized set methods
        Set<String> commonProperties = new HashSet<String>(getMethods.keySet());
        commonProperties.retainAll(setMethods.keySet());

        // Report method pairs
        for (String propName : commonProperties) {
            MethodAnnotation getMethod = getMethods.get(propName);
            MethodAnnotation setMethod = setMethods.get(propName);

            bugReporter.reportBug(new BugInstance(this, "UG_SYNC_SET_UNSYNC_GET", NORMAL_PRIORITY).addClass(prevClassName)
                    .addMethod(getMethod).addMethod(setMethod));
        }
        getMethods.clear();
        setMethods.clear();
    }

    @Override
    public void visit(JavaClass obj) {
        report();
        prevClassName = getDottedClassName();
    }

    @Override
    public void visit(Method obj) {
        int flags = obj.getAccessFlags();
        if ((flags & doNotConsider) != 0)
            return;
        String name = obj.getName();
        boolean isSynchronized = (flags & ACC_SYNCHRONIZED) != 0;
        /*
         * String sig = obj.getSignature(); char firstArg = sig.charAt(1); char
         * returnValue = sig.charAt(1 + sig.indexOf(')')); boolean firstArgIsRef
         * = (firstArg == 'L') || (firstArg == '['); boolean returnValueIsRef =
         * (returnValue == 'L') || (returnValue == '[');
         * 
         * System.out.println(className + "." + name + " " + firstArgIsRef + " "
         * + returnValueIsRef + " " + isSynchronized + " " + isNative );
         */
        if (name.startsWith("get") && !isSynchronized
        // && returnValueIsRef
        ) {
            getMethods.put(name.substring(3), MethodAnnotation.fromVisitedMethod(this));
        } else if (name.startsWith("set") && isSynchronized
        // && firstArgIsRef
        ) {
            setMethods.put(name.substring(3), MethodAnnotation.fromVisitedMethod(this));
        }
    }
}