JavaParser.java

/* 
  Copyright (C) 2013 Raquel Pau and Albert Coroleu.
 
 Walkmod 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 3 of the License, or
 (at your option) any later version.
 
 Walkmod 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 Walkmod.  If not, see <http://www.gnu.org/licenses/>.*/
package org.walkmod.javalang;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;

import org.walkmod.javalang.ast.CompilationUnit;

/**
 * <p>
 * This class was generated automatically by javacc, do not edit.
 * </p>
 * <p>
 * Parse Java 1.5 source code and creates Abstract Syntax Tree classes.
 * </p>
 * <p>
 * <b>Note:</b> To use this parser asynchronously, disable de parser cache by
 * calling the method {@link setCacheParser} with <code>false</code> as
 * argument.
 * </p>
 *
 * @author Julio Vilmar Gesser
 */
public final class JavaParser {

	private static ASTParser parser;

	private static boolean cacheParser = true;

	private JavaParser() {
	}

	/**
	 * Changes the way that the parser acts when starts to parse. If the parser
	 * cache is enabled, only one insance of this object will be used in every
	 * call to parse methods. If this parser is intend to be used asynchonously,
	 * the cache must be disabled setting this flag to <code>false</code>. By
	 * default, the cache is enabled.
	 * 
	 * @param value
	 *            <code>false</code> to disable the parser instance cache.
	 */
	public static void setCacheParser(boolean value) {
		cacheParser = value;
		if (!value) {
			parser = null;
		}
	}

	/**
	 * Parses the Java code contained in the {@link InputStream} and returns a
	 * {@link CompilationUnit} that represents it.
	 * 
	 * @param in
	 *            {@link InputStream} containing Java source code
	 * @param encoding
	 *            encoding of the source code
	 * @return CompilationUnit representing the Java source code
	 * @throws ParseException
	 *             if the source code has parser errors
	 */
	public static CompilationUnit parse(InputStream in, String encoding)
			throws ParseException {
		if (cacheParser) {
			if (parser == null) {
				parser = new ASTParser(in, encoding);
			} else {
				parser.reset(in, encoding);
			}
			return parser.CompilationUnit();
		}
		return new ASTParser(in, encoding).CompilationUnit();
	}

	/**
	 * Parses the Java code contained in the {@link InputStream} and returns a
	 * {@link CompilationUnit} that represents it.
	 * 
	 * @param in
	 *            {@link InputStream} containing Java source code
	 * @return CompilationUnit representing the Java source code
	 * @throws ParseException
	 *             if the source code has parser errors
	 */
	public static CompilationUnit parse(InputStream in) throws ParseException {
		return parse(in, null);
	}

	/**
	 * Parses the Java code contained in a {@link File} and returns a
	 * {@link CompilationUnit} that represents it.
	 * 
	 * @param file
	 *            {@link File} containing Java source code
	 * @param encoding
	 *            encoding of the source code
	 * @return CompilationUnit representing the Java source code
	 * @throws ParseException
	 *             if the source code has parser errors
	 * @throws IOException
	 */
	public static CompilationUnit parse(File file, String encoding)
			throws ParseException, IOException {
		FileInputStream in = new FileInputStream(file);
		try {
			return parse(in, encoding);
		} finally {
			in.close();
		}
	}

	/**
	 * Parses the Java code contained in a {@link File} and returns a
	 * {@link CompilationUnit} that represents it.
	 * 
	 * @param file
	 *            {@link File} containing Java source code
	 * @return CompilationUnit representing the Java source code
	 * @throws ParseException
	 *             if the source code has parser errors
	 * @throws IOException
	 */
	public static CompilationUnit parse(File file) throws ParseException,
			IOException {
		return parse(file, null);
	}
}