NameValidator.java

/*******************************************************************************
 * Copyright (c) 2015 Jeff Martin.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the GNU Lesser General Public
 * License v3.0 which accompanies this distribution, and is available at
 * http://www.gnu.org/licenses/lgpl.html
 *
 * Contributors:
 * Jeff Martin - initial API and implementation
 ******************************************************************************/
package cuchaz.enigma.mapping;

import java.util.Arrays;
import java.util.List;
import java.util.regex.Pattern;

import javassist.bytecode.Descriptor;

public class NameValidator
{
	
	private static final Pattern IdentifierPattern;
	private static final Pattern ClassPattern;
	private static final List<String> ReservedWords = Arrays.asList("abstract",
		"continue", "for", "new", "switch", "assert", "default", "goto",
		"package", "synchronized", "boolean", "do", "if", "private", "this",
		"break", "double", "implements", "protected", "throw", "byte", "else",
		"import", "public", "throws", "case", "enum", "instanceof", "return",
		"transient", "catch", "extends", "int", "short", "try", "char",
		"final", "interface", "static", "void", "class", "finally", "long",
		"strictfp", "volatile", "const", "float", "native", "super", "while");
	
	static
	{
		
		// java allows all kinds of weird characters...
		StringBuilder startChars = new StringBuilder();
		StringBuilder partChars = new StringBuilder();
		for(int i = Character.MIN_CODE_POINT; i <= Character.MAX_CODE_POINT; i++)
		{
			if(Character.isJavaIdentifierStart(i))
				startChars.appendCodePoint(i);
			if(Character.isJavaIdentifierPart(i))
				partChars.appendCodePoint(i);
		}
		
		String identifierRegex = "[A-Za-z_<][A-Za-z0-9_>]*";
		IdentifierPattern = Pattern.compile(identifierRegex);
		ClassPattern =
			Pattern.compile(String.format("^(%s(\\.|/))*(%s)$",
				identifierRegex, identifierRegex));
	}
	
	public static String validateClassName(String name, boolean packageRequired)
	{
		if(name == null)
			return null;
		if(!ClassPattern.matcher(name).matches()
			|| ReservedWords.contains(name))
			throw new IllegalNameException(name,
				"This doesn't look like a legal class name");
		if(packageRequired && new ClassEntry(name).getPackageName() == null)
			throw new IllegalNameException(name, "Class must be in a package");
		return Descriptor.toJvmName(name);
	}
	
	public static String validateFieldName(String name)
	{
		if(name == null)
			return null;
		if(!IdentifierPattern.matcher(name).matches()
			|| ReservedWords.contains(name))
			throw new IllegalNameException(name,
				"This doesn't look like a legal identifier");
		return name;
	}
	
	public static String validateMethodName(String name)
	{
		return validateFieldName(name);
	}
	
	public static String validateArgumentName(String name)
	{
		return validateFieldName(name);
	}
}