This FileFilter will format a file as a hex dump.

src/com/webcodepro/applecommander/storage/HexDumpFileFilter.java

@@ -0,0 +1,110 @@
+/*
+ * AppleCommander - An Apple ][ image utility.
+ * Copyright (C) 2002-2003 by Robert Greene
+ * robgreene at users.sourceforge.net
+ *
+ * This program is free software; you can redistribute it and/or modify it 
+ * under the terms of the GNU General Public License as published by the 
+ * Free Software Foundation; either version 2 of the License, or (at your 
+ * option) any later version.
+ *
+ * This program 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 General Public License 
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License along 
+ * with this program; if not, write to the Free Software Foundation, Inc., 
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+package com.webcodepro.applecommander.storage;
+
+import java.io.ByteArrayOutputStream;
+import java.io.PrintWriter;
+
+/**
+ * Filter the given file data to be the appropriate length.
+ * <p>
+ * Date created: Nov 2, 2002 9:07:52 PM
+ * @author: Rob Greene
+ */
+public class HexDumpFileFilter implements FileFilter {
+	/**
+	 * This is the number of bytes to display per line.
+	 */
+	private static final int BYTES_PER_LINE = 16;
+	/**
+	 * This is the ASCII space character as used by the Apple ][.
+	 * The high bit is off.
+	 */
+	private static final int APPLE_SPACE = 0x20;
+	
+	/**
+	 * Constructor for BinaryFileFilter.
+	 */
+	public HexDumpFileFilter() {
+		super();
+	}
+
+	/**
+	 * Create the hex dump format.  This is in the general form of:<br>
+	 * MMMMMM: HH HH HH HH HH HH HH HH  HH HH HH HH HH HH HH HH  AAAAAAAA AAAAAAAA<br>
+	 * Where MMMMMM = memory address, HH = hex byte, and
+	 * A = ASCII character.
+	 * @see com.webcodepro.applecommander.storage.FileFilter#filter(byte[])
+	 */
+	public byte[] filter(FileEntry fileEntry) {
+		byte[] fileData = fileEntry.getFileData();
+		ByteArrayOutputStream output = new ByteArrayOutputStream();
+		PrintWriter printer = new PrintWriter(output);
+		printer.print(" Offset  ");
+		printer.print("Hex Data                                          ");
+		printer.println("Characters");
+		printer.print("=======  ");
+		printer.print("================================================  ");
+		printer.println("=================");
+		for (int offset=0; offset<fileData.length; offset+= BYTES_PER_LINE) {
+			printer.print("$");
+			printer.print(AppleUtil.getFormatted3ByteAddress(offset));
+			printer.print("  ");
+			for (int b=0; b<BYTES_PER_LINE; b++) {
+				if (b == BYTES_PER_LINE / 2) printer.print(' ');
+				int index = offset+b;
+				printer.print( (index < fileData.length) ?
+					AppleUtil.getFormattedByte(fileData[index]) : "..");
+				printer.print(' ');
+			}
+			printer.print(' ');
+			for (int a=0; a<BYTES_PER_LINE; a++) {
+				if (a == BYTES_PER_LINE / 2) printer.print(' ');
+				int index = offset+a;
+				if (index < fileData.length) {
+					char ch = (char) (fileData[index] & 0x7f);
+					if ((byte)ch >= (byte)APPLE_SPACE) {
+						printer.print(ch);
+					} else {
+						printer.print('.');
+					}
+				} else {
+					printer.print(' ');
+				}
+			}
+			printer.println();
+		}
+		printer.println("** END **");
+		printer.flush();
+		printer.close();
+		return output.toByteArray();
+	}
+
+	/**
+	 * Give suggested file name.
+	 */
+	public String getSuggestedFileName(FileEntry fileEntry) {
+		String fileName = fileEntry.getFilename().trim();
+		if (!fileName.toLowerCase().endsWith(".txt")) {
+			fileName = fileName + ".txt";
+		}
+		return fileName;
+	}
+}