fb-contrib-commit

[Dave B. <dbr...@us...>]

Update of /cvsroot/fb-contrib/fb-contrib/src/com/mebigfatguy/fbcontrib/detect
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv25229/src/com/mebigfatguy/fbcontrib/detect

Added Files:
	CustomBuiltXML.java 
Log Message:
initial checkin - new CBX detector

--- NEW FILE: CustomBuiltXML.java ---
/*
 * fb-contrib - Auxilliary detectors for Java programs
 * Copyright (C) 2005 Dave Brosius
 * 
 * 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 com.mebigfatguy.fbcontrib.detect;

import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

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.OpcodeStack;
import edu.umd.cs.findbugs.StatelessDetector;

public class CustomBuiltXML extends BytecodeScanningDetector implements StatelessDetector 
{
	private static final List<Pattern> xmlPatterns = new ArrayList<Pattern>();
	static {
		xmlPatterns.add(Pattern.compile(".*<[a-zA-Z_](\\w)*>.*"));
		xmlPatterns.add(Pattern.compile(".*</[a-zA-Z_](\\w)*>.*"));
		xmlPatterns.add(Pattern.compile(".*<[a-zA-Z_](\\w)*/>.*"));
		xmlPatterns.add(Pattern.compile(".*<(//)?$"));
		xmlPatterns.add(Pattern.compile("^(//)?>.*"));
		xmlPatterns.add(Pattern.compile(".*=(\\s)*[\"'].*"));
		xmlPatterns.add(Pattern.compile("^[\"']>.*"));
		xmlPatterns.add(Pattern.compile(".*<!\\[CDATA\\[.*", Pattern.CASE_INSENSITIVE));
		xmlPatterns.add(Pattern.compile(".*\\]\\]>.*"));
		xmlPatterns.add(Pattern.compile(".*xmlns:.*"));		
	}
	private static final String CBX_MIN_REPORTABLE_ITEMS = "fb-contrib.cbx.minxmlitems";
	private BugReporter bugReporter;
	private OpcodeStack stack = new OpcodeStack();
	private int xmlItemCount = 0;
	private int lowReportingThreshold;
	private int midReportingThreshold;
	private int highReportingThreshold;
	private int firstPC;
	
	   /**
     * constructs a CBX detector given the reporter to report bugs on

     * @param bugReporter the sync of bug reports
     */
	public CustomBuiltXML(BugReporter bugReporter) {
		this.bugReporter = bugReporter;
		
		lowReportingThreshold = Integer.getInteger(CBX_MIN_REPORTABLE_ITEMS, 5);
		midReportingThreshold = lowReportingThreshold << 1;
		highReportingThreshold = lowReportingThreshold << 2;
	}
	
	/**
	 * clone this detector so that it can be a StatelessDetector
	 * 
	 * @return a clone of this object
	 */
	@Override
	public Object clone() throws CloneNotSupportedException {
		return super.clone();
	}
	
	/**
	 * overrides the visitor reset the opcode stack
	 * 
	 * @param obj the code object of the currently parsed method
	 */	
	public void visitCode(Code obj) {
		stack.resetForMethodEntry(this);
		xmlItemCount = 0;
		firstPC = -1;
		super.visitCode(obj);
		if (xmlItemCount >= lowReportingThreshold) {
			bugReporter.reportBug( new BugInstance( this,
													"CBX_CUSTOM_BUILT_XML",
													(xmlItemCount >= highReportingThreshold) ? HIGH_PRIORITY :
													(xmlItemCount >= midReportingThreshold) ? NORMAL_PRIORITY :
													LOW_PRIORITY)
										.addClass(this)
										.addMethod(this)
										.addSourceLine(this, firstPC));
														
		}
	}
	
	/**
	 * overrides the visitor to find String concatenations including xml strings
	 * 
	 * @param seen the opcode that is being visited
	 */	
	public void sawOpcode(int seen) {
		String strCon = null;
		
		try {
			if (seen == INVOKESPECIAL) {
				String clsName = getClassConstantOperand();
				if ("java/lang/StringBuffer".equals(clsName) || "java/lang/StringBuilder".equals(clsName)) {
					String methodName = getNameConstantOperand();
					String methodSig = getSigConstantOperand();
					if ("<init>".equals(methodName) && ("(Ljava/lang/String;)L" + clsName + ";").equals(methodSig)) {
						if (stack.getStackDepth() > 0) {
							OpcodeStack.Item itm = stack.getStackItem(0);
							strCon = (String)itm.getConstant();
						}
					}
				}
			} else if (seen == INVOKEVIRTUAL) {
				String clsName = getClassConstantOperand();
				if ("java/lang/StringBuffer".equals(clsName) || "java/lang/StringBuilder".equals(clsName)) {
					String methodName = getNameConstantOperand();
					String methodSig = getSigConstantOperand();
					if ("append".equals(methodName) && ("(Ljava/lang/String;)L" + clsName + ";").equals(methodSig)) {
						if (stack.getStackDepth() > 0) {
							OpcodeStack.Item itm = stack.getStackItem(0);
							strCon = (String)itm.getConstant();
						}
					}
				}
			}
			
			if (strCon != null) {
				if (strCon.trim().length() == 0)
					return;
				
				for (Pattern p : xmlPatterns) {
					Matcher m = p.matcher(strCon);
					if (m.matches()) {
						xmlItemCount++;
						if (firstPC < 0)
							firstPC = getPC();
						break;
					}
				}
			}
		} finally {
			stack.sawOpcode(this, seen);
		}
	}
}