HexDump.java

/*
 * Copyright (c) 2013 Allogy Interactive.
 *
 * 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 com.sun.pdfview;

import java.io.IOException;
import java.io.RandomAccessFile;

public class HexDump {

    public static void printData(byte[] data) {
        char[] parts = new char[17];
        int partsloc = 0;
        for (int i = 0; i < data.length; i++) {
            int d = ((int) data[i]) & 0xff;
            if (d == 0) {
                parts[partsloc++] = '.';
            } else if (d < 32 || d >= 127) {
                parts[partsloc++] = '?';
            } else {
                parts[partsloc++] = (char) d;
            }
            if (i % 16 == 0) {
                int start = Integer.toHexString(data.length).length();
                int end = Integer.toHexString(i).length();

                for (int j = start; j > end; j--) {
                    System.out.print("0");
                }
                System.out.print(Integer.toHexString(i) + ": ");
            }
            if (d < 16) {
                System.out.print("0" + Integer.toHexString(d));
            } else {
                System.out.print(Integer.toHexString(d));
            }
            if ((i & 15) == 15 || i == data.length - 1) {
                System.out.println("      " + new String(parts));
                partsloc = 0;
            } else if ((i & 7) == 7) {
                System.out.print("  ");
                parts[partsloc++] = ' ';
            } else if ((i & 1) == 1) {
                System.out.print(" ");
            }
        }
        System.out.println();
    }

    public static void main(String args[]) {
        if (args.length != 1) {
            System.out.println("Usage: ");
            System.out.println("    HexDump <filename>");
            System.exit(-1);
        }

        try {
            RandomAccessFile raf = new RandomAccessFile(args[0], "r");

            int size = (int) raf.length();
            byte[] data = new byte[size];

            raf.readFully(data);
            printData(data);
        } catch (IOException ioe) {
            ioe.printStackTrace();
        }
    }
}