/*
 * 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.detect;
import edu.umd.cs.findbugs.*;
import java.util.*;
import java.io.PrintStream;
import org.apache.bcel.classfile.*;
import java.util.zip.*;
import java.io.*;

import edu.umd.cs.pugh.visitclass.DismantleBytecode;
import edu.umd.cs.pugh.visitclass.Constants2;

public class FindFieldSelfAssignment extends BytecodeScanningDetector implements   Constants2 {
    private BugReporter bugReporter;
    int state;


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

   JavaClass jClass;
   public void visit(JavaClass obj) {
	jClass = obj;
	}
   public void visit(Code obj) {
	state = 0;
	super.visit(obj);
	}


    String f;
    public void sawOpcode(int seen) {

	switch (state) {
	case 0:
		if (seen == ALOAD_0)
			state = 1;
		break;
	case 1:
		if (seen == ALOAD_0)
			state = 2;
		else
			state = 0;
		break;
	case 2:
		if (seen == GETFIELD) {
			state = 3;
			f = refConstant;
			}
		else
			state = 0;
		break;
	case 3:
		if (seen == PUTFIELD && refConstant.equals(f)) {

                                bugReporter.reportBug(new BugInstance("SA_FIELD_SELF_ASSIGNMENT", NORMAL_PRIORITY)
                                        .addClass(className)
                                        .addMethod(className, methodName, methodSig)
                                        .addField(betterClassConstant, nameConstant, 
						betterSigConstant, false)
                                        .addSourceLine(this)

					);
			}
		state = 0;
		}
	}
		
}

Check for self assignment of fields
Check for self assignment of fields


git-svn-id: e7d6bde23f017c9ff4efd468d79d66def666766b@1765 eae3c2d3-9b19-0410-a86e-396b6ccb6ab3
