org.apache.cocoon.components.language.programming.java.Javac.java Source code

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Here is the source code for org.apache.cocoon.components.language.programming.java.Javac.java

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/*
 * Copyright 1999-2004 The Apache Software Foundation.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.cocoon.components.language.programming.java;

import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import java.util.NoSuchElementException;
import java.util.StringTokenizer;

import org.apache.cocoon.components.language.programming.CompilerError;
import org.apache.commons.lang.SystemUtils;

/**
 * This class wraps the Sun's Javac Compiler.
 *
 * @author <a href="mailto:stefano@apache.org">Stefano Mazzocchi</a>
 * @version CVS $Id: Javac.java 156687 2005-03-09 20:55:09Z antonio $
 * @since 2.0
 */

public class Javac extends AbstractJavaCompiler {

    public Javac() {
        // EMPTY
    }

    /**
     * Compile a source file yielding a loadable class file.
     *
     * <code>null</code> if it is the platform's default encoding
     * @exception IOException If an error occurs during compilation
     */
    public boolean compile() throws IOException {

        ByteArrayOutputStream err = new ByteArrayOutputStream();

        boolean result;
        if (!SystemUtils.IS_JAVA_1_3) { // For Java 1.4 and 1.5
            PrintWriter pw = new PrintWriter(err);
            result = com.sun.tools.javac.Main.compile(toStringArray(fillArguments(new ArrayList())), pw) == 0;
        } else {
            sun.tools.javac.Main compiler = new sun.tools.javac.Main(err, "javac");
            result = compiler.compile(toStringArray(fillArguments(new ArrayList())));
        }
        this.errors = new ByteArrayInputStream(err.toByteArray());
        return result;
    }

    /**
     * Parse the compiler error stream to produce a list of
     * <code>CompilerError</code>s
     *
     * @param input The error stream
     * @return The list of compiler error messages
     * @exception IOException If an error occurs during message collection
     */
    protected List parseStream(BufferedReader input) throws IOException {
        List errors = new ArrayList();
        String line = null;
        StringBuffer buffer = null;

        while (true) {
            // cleanup the buffer
            buffer = new StringBuffer(); // this is quicker than clearing it

            // most errors terminate with the '^' char
            do {
                if ((line = input.readLine()) == null) {
                    if (buffer.length() > 0) {
                        // There's an error which doesn't end with a '^'
                        errors.add(new CompilerError("\n" + buffer.toString()));
                    }
                    return errors;
                }
                buffer.append(line);
                buffer.append('\n');
            } while (!line.endsWith("^"));

            // add the error bean
            errors.add(parseModernError(buffer.toString()));
        }
    }

    /**
     * Parse an individual compiler error message with modern style.
     *
     * @param error The error text
     * @return A messaged <code>CompilerError</code>
     */
    private CompilerError parseModernError(String error) {
        StringTokenizer tokens = new StringTokenizer(error, ":");
        try {
            String file = tokens.nextToken();
            if (file.length() == 1)
                file = new StringBuffer(file).append(":").append(tokens.nextToken()).toString();
            int line = Integer.parseInt(tokens.nextToken());

            String message = tokens.nextToken("\n").substring(1);
            String context = tokens.nextToken("\n");
            String pointer = tokens.nextToken("\n");
            int startcolumn = pointer.indexOf("^");
            int endcolumn = context.indexOf(" ", startcolumn);
            if (endcolumn == -1) {
                endcolumn = context.length();
            }
            return new CompilerError(file, false, line, startcolumn, line, endcolumn, message);
        } catch (NoSuchElementException nse) {
            return new CompilerError("no more tokens - could not parse error message: " + error);
        } catch (Exception nse) {
            return new CompilerError("could not parse error message: " + error);
        }
    }

    public String toString() {
        return "Sun Javac Compiler";
    }
}