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A static code analysis tool for ColdFusion (in the spirit of FindBugs and Lint). With CFLint, you are able to analyze your ColdFusion code base for code violations.

There is a newer version: 1.5.0

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package com.cflint.plugins.core;

import com.cflint.BugInfo;
import com.cflint.BugList;
import com.cflint.plugins.CFLintScannerAdapter;
import com.cflint.plugins.Context;

import cfml.parsing.cfscript.CFBinaryExpression;
import cfml.parsing.cfscript.CFExpression;

public class ComplexBooleanExpressionChecker extends CFLintScannerAdapter {
	final String severity = "WARNING";

	protected int complexThreshold = 10;

	@Override
	public void expression(final CFExpression expression, final Context context, final BugList bugs) {
		if (expression instanceof CFBinaryExpression) {
			final String code = expression.Decompile(0).toLowerCase();

			if (isComplex(code, complexThreshold)) {
				final int lineNo = currentLine(expression, context);

				complexBooleanExpression(lineNo, context, bugs);
			}
		}
	}

	protected boolean isComplex(final String code, final int complexThreshold) {
		final int noAnds = noSubstrings(code, " && ") + noSubstrings(code, " and ");
		final int noOrs = noSubstrings(code, " || ") + noSubstrings(code, " or ");
		final int noNots = noSubstrings(code, " ! ") + noSubstrings(code, " not ");

		// This is just a rough heuristic
		// lots of and's or or's on their own is usually easy to understand
		// but combine them together and it gets hard to understand very quickly
		return (noAnds * noOrs + noNots + noAnds + noOrs) > complexThreshold;
	}

	protected int noSubstrings(final String string, final String substring) {
		int lastIndex = 0;
		int count = 0;

		while (lastIndex != -1) {
			lastIndex = string.indexOf(substring, lastIndex);

			if (lastIndex != -1) {
				count++;
				lastIndex += substring.length();
			}
		}

		return count;
	}

	public void complexBooleanExpression(final int lineNo, final Context context, final BugList bugs) {
		bugs.add(
				new BugInfo.BugInfoBuilder().setLine(lineNo).setMessageCode("COMPLEX_BOOLEAN_CHECK")
						.setSeverity(severity).setFilename(context.getFilename()).setMessage("Boolean expession at "
								+ lineNo + " is too complex. Consider simplifying or moving to a named method.")
						.build());
	}

}