added NewlineAtEndOfFile check, contributed by Christopher Lenz

src/checkstyle/com/puppycrawl/tools/checkstyle/checks/LineSeparatorOption.java

@@ -0,0 +1,91 @@
+////////////////////////////////////////////////////////////////////////////////
+// checkstyle: Checks Java source code for adherence to a set of rules.
+// Copyright (C) 2001-2002  Oliver Burn
+//
+// 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+////////////////////////////////////////////////////////////////////////////////
+package com.puppycrawl.tools.checkstyle.checks;
+
+import java.util.Map;
+import java.util.HashMap;
+
+/**
+ * Represents the options for line separator settings.
+ *
+ * @author lkuehne
+ * @see NewlineAtEndOfFileCheck
+ */
+public final class LineSeparatorOption extends AbstractOption
+{
+    /** maps from a string representation to an option */
+    private static final Map STR_TO_OPT = new HashMap();
+
+    /** Windows-style line separators **/
+    public static final LineSeparatorOption CRLF =
+      new LineSeparatorOption("crlf", "\r\n");
+
+    /** Mac-style line separators **/
+    public static final LineSeparatorOption CR =
+        new LineSeparatorOption("cr", "\r");
+
+    /** Unix-style line separators **/
+    public static final LineSeparatorOption LF =
+        new LineSeparatorOption("lf", "\n");
+
+    /** System default line separators **/
+    public static final LineSeparatorOption SYSTEM = new LineSeparatorOption(
+        "system", System.getProperty("line.separator"));
+
+    /** the line separator representation */
+    private final String mLineSeparator;
+
+    /**
+     * Creates a new <code>LineSeparatorOption</code> instance.
+     * @param aStrRep the string representation
+     * @param aSep the line separator, e.g. "\r\n"
+     */
+    private LineSeparatorOption(String aStrRep, String aSep)
+    {
+        super(aStrRep);
+        mLineSeparator = aSep;
+    }
+
+    /**
+     * @param aBytes a bytes array to check
+     * @return if aBytes is equal to the byte representation
+     * of this line separator
+     */
+    public boolean matches(byte[] aBytes)
+    {
+        final String s = new String(aBytes);
+        return s.equals(mLineSeparator);
+    }
+
+    /**
+     * @return the length of the file separator,
+     * e.g. 1 for CR, 2 for CRLF, ...
+     */
+    public int length()
+    {
+        return mLineSeparator.length();
+    }
+
+    /** @see com.puppycrawl.tools.checkstyle.checks.AbstractOption */
+    protected Map getStrToOpt()
+    {
+        return STR_TO_OPT;
+    }
+
+}

src/checkstyle/com/puppycrawl/tools/checkstyle/checks/NewlineAtEndOfFileCheck.java

@@ -0,0 +1,170 @@
+////////////////////////////////////////////////////////////////////////////////
+// checkstyle: Checks Java source code for adherence to a set of rules.
+// Copyright (C) 2001-2002  Oliver Burn
+//
+// 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+////////////////////////////////////////////////////////////////////////////////
+package com.puppycrawl.tools.checkstyle.checks;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.RandomAccessFile;
+
+import com.puppycrawl.tools.checkstyle.Defn;
+import com.puppycrawl.tools.checkstyle.api.AbstractFileSetCheck;
+import com.puppycrawl.tools.checkstyle.api.LocalizedMessage;
+import com.puppycrawl.tools.checkstyle.api.MessageDispatcher;
+import com.puppycrawl.tools.checkstyle.api.LocalizedMessages;
+import org.apache.commons.beanutils.ConversionException;
+
+/**
+ * <p>
+ * Checks that there is a newline at the end of each file.
+ * </p>
+ * <p> 
+ * An example of how to configure the check is:
+ * </p>
+ * <pre>
+ * &lt;module name="NewlineAtEndOfFile"/&gt;</pre>
+ * <p>
+ * This will check against the platform-specific default line separator.
+ * </p>
+ * <p>
+ * It is also possible to enforce the use of a specific line-separator across
+ * platforms, with the 'lineSeparator' property:
+ * </p>
+ * <pre>
+ * &lt;module name="NewlineAtEndOfFile"&gt;
+ *   &lt;property name="lineSeparator" value="lf"/&gt;
+ * &lt;/module&gt;</pre>
+ * <p>
+ * Valid values for the 'lineSeparator' property are 'system' (system default),
+ * 'crlf' (windows), 'cr' (mac) and 'lf' (unix).
+ * </p>
+ * 
+ * @author Christopher Lenz
+ * @author lkuehne
+ * @version 1.0
+ */
+public class NewlineAtEndOfFileCheck
+    extends AbstractFileSetCheck
+{
+    /** the line separator to check against. */
+    private LineSeparatorOption mLineSeparator =
+        LineSeparatorOption.SYSTEM;
+
+    /** @see com.puppycrawl.tools.checkstyle.api.Check */
+    public int[] getDefaultTokens()
+    {
+        return new int[0];
+    }
+
+    /**
+     * @see com.puppycrawl.tools.checkstyle.api.FileSetCheck#process
+     */
+    public void process(File[] aFiles)
+    {
+        final File[] files = filter(aFiles);
+        final MessageDispatcher dispatcher = getMessageDispatcher();
+        for (int i = 0; i < files.length; i++) {
+            final File file = files[i];
+            final String path = file.getPath();
+            dispatcher.fireFileStarted(path);
+            RandomAccessFile randomAccessFile = null;
+            try {
+                randomAccessFile = new RandomAccessFile(file, "r");
+                if (!endsWithNewline(randomAccessFile)) {
+                    log(0, "noNewlineAtEOF", path);
+                }
+            }
+            catch (IOException e) {
+                logIOException(e);
+            }
+            finally {
+                if (randomAccessFile != null) {
+                    try {
+                        randomAccessFile.close();
+                    }
+                    catch (IOException e) {
+                        logIOException(e);
+                    }
+                }
+            }
+            final LocalizedMessages messageList = getMessageCollector();
+            final LocalizedMessage[] messages = messageList.getMessages();
+            dispatcher.fireErrors(path, messages);
+            dispatcher.fireFileFinished(path);
+        }
+    }
+
+    /**
+     * Sets the line separator to one of 'crlf', 'lf' or 'cr'.
+     * 
+     * @param aLineSeparator The line separator to set
+     * @throws IllegalArgumentException If the specified line separator is not 
+     *         one of 'crlf', 'lf' or 'cr'
+     */
+    public void setLineSeparator(String aLineSeparator)
+    {
+        AbstractOption option =
+            LineSeparatorOption.SYSTEM.decode(aLineSeparator);
+
+        if (option == null) {
+            throw new ConversionException("unable to parse " + aLineSeparator);
+        }
+
+        mLineSeparator = (LineSeparatorOption) option;
+    }
+
+    /**
+     * Checks whether the content provided by the Reader ends with the platform
+     * specific line separator.
+     * @param aRandomAccessFile The reader for the content to check
+     * @return boolean Whether the content ends with a line separator
+     * @throws IOException When an IO error occurred while reading from the
+     *         provided reader
+     */
+    private boolean endsWithNewline(RandomAccessFile aRandomAccessFile)
+        throws IOException
+    {
+        final int len = mLineSeparator.length();
+        if (aRandomAccessFile.length() < len) {
+            return false;
+        }
+        aRandomAccessFile.seek(aRandomAccessFile.length() - len);
+        final byte lastBytes[] = new byte[len];
+        aRandomAccessFile.read(lastBytes);
+        return mLineSeparator.matches(lastBytes);
+    }
+
+    /**
+     * Helper method to log an IO exception.
+     * @param aEx the exception that occured
+     */
+    private void logIOException(IOException aEx)
+    {
+        String[] args = null;
+        String key = "general.fileNotFound";
+        if (!(aEx instanceof FileNotFoundException)) {
+            args = new String[] {aEx.getMessage()};
+            key = "general.exception";
+        }
+        LocalizedMessage message =
+            new LocalizedMessage(0, Defn.CHECKSTYLE_BUNDLE, key, args);
+        getMessageCollector().add(message);
+    }
+
+}