HeaderTask.java

/*
 * $Id: HeaderTask.java 4971 2009-02-02 06:44:38Z lsantha $
 *
 * Copyright (C) 2003-2009 JNode.org
 *
 * 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., 
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
 
package org.jnode.ant.taskdefs;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import org.apache.tools.ant.BuildException;

/**
 * @author Ewout Prangsma (epr@users.sourceforge.net)
 */
public class HeaderTask extends FileSetTask {

    private File headerFile;
    private String[] header;

    private boolean update = false;

    private boolean compareHeader(String[] lines, String[] header) {
        final int linesCnt = lines.length;
        final int hdrCnt = header.length;

        for (int i = 0; i < linesCnt; i++) {
            final String line = lines[i];
            if (i < hdrCnt) {
                if (!compareLine(line, header[i])) {
                    return false;
                }
            } else {
                String trimmedLine = line.trim();
                if (trimmedLine.startsWith("package")) {
                    return true;
                }
                if (trimmedLine.length() > 0) {
                    return false;
                }
            }
        }

        return false;
    }

    private boolean compareLine(String line, String hdrLine) {
        if ((line.indexOf('$') >= 0) && (hdrLine.indexOf('$') >= 0)) {
            return true;
        }
        return line.trim().equals(hdrLine.trim());
    }

    protected int doExecute() throws BuildException {
        if (headerFile == null) {
            throw new BuildException("HeaderFile must be set");
        }
        try {
            header = readFile(headerFile);
            return processFiles();
        } catch (IOException ex) {
            throw new BuildException(ex);
        }
    }

    public final File getHeaderFile() {
        return headerFile;
    }

    public final boolean isUpdate() {
        return update;
    }

    @Override
    protected boolean processFile(File file) throws IOException {
        final String[] inp = readFile(file);
        boolean fileUpdated = false;
        if (!compareHeader(inp, header)) {
            if (update) {
                log("Updating " + file);
                writeUpdateFile(file, inp, header);
                fileUpdated = true;
            } else {
                log("Wrong header in " + file);
            }
        }
        return fileUpdated;
    }

    private void writeUpdateFile(File file, String[] lines, String[] header) throws IOException {
        PrintWriter out = new PrintWriter(new FileWriter(file));
        try {
            final int hdrCnt = header.length;
            for (int i = 0; i < hdrCnt; i++) {
                out.println(header[i]);
            }

            final int linesCnt = lines.length;
            boolean write = false;
            for (int i = 0; i < linesCnt; i++) {
                final String line = lines[i];
                String trimmedLine = line.trim();
                if (trimmedLine.startsWith("package")) {
                    write = true;
                }
                if (write) {
                    out.println(lines[i]);
                }
            }
        } finally {
            out.close();
        }
    }


    private String[] readFile(File file) throws IOException {
        final BufferedReader in = new BufferedReader(new FileReader(file));
        try {
            final ArrayList<String> lines = new ArrayList<String>();
            String line;
            while ((line = in.readLine()) != null) {
                lines.add(line);
            }
            return lines.toArray(new String[lines.size()]);
        } finally {
            in.close();
        }
    }

    public final void setHeaderFile(File headerFile) {
        this.headerFile = headerFile;
    }

    public final void setUpdate(boolean update) {
        this.update = update;
    }
}