Package com.webcodepro.applecommander.util

Class AppleUtil

java.lang.Object
com.webcodepro.applecommander.util.AppleUtil
public class AppleUtil extends Object
This class contains helper methods for dealing with Apple2 data.

Date created: Oct 5, 2002 4:16:16 PM

  • Constructor Summary

    Constructors
    Constructor
    Description
    AppleUtil()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    static void
    changeImageOrderByBlock(ImageOrder sourceOrder, ImageOrder targetOrder)
    Change ImageOrder from source order to target order by copying block by block.
    static void
    changeImageOrderByTrackAndSector(ImageOrder sourceOrder, ImageOrder targetOrder)
    Change ImageOrder from source order to target order by copying sector by sector.
    static byte
    clearBit(byte byt, int bit)
    Clear a specific bit (turn it off).
    static int
    convertFormattedWord(String word)
    Convert a typical Apple formatted word.
    static int
    get3ByteValue(byte[] buffer, int offset)
    Compute the value of a 3 byte value.
    static byte[]
    getApplesoftFloat(double number)
    Convert a double number to an Applesoft float.
    static int
    getBitCount(byte byt)
    Count the number of bits set in a byte.
    static String
    getFormatted3ByteAddress(int addr)
    Format a 3 byte value as hexadecimal.
    static String
    getFormattedByte(int byt)
    Format a byte value as hexadecimal.
    static String
    getFormattedWord(int word)
    Format a word value as hexadecimal.
    static String
    getHexDump(byte[] bytes)
    Generate a simple hex dump from the given byte array.
    static String
    getHexDump(int address, byte[] bytes)
     
    static long
    getLongValue(byte[] buffer, int offset)
    Compute the value of a 4 byte value.
    static String
    getNiceFilename(String filename)
    Make a "nice" filename.
    static Date
    getPascalDate(byte[] buffer, int offset)
    Extract a Pascal date from the buffer.
    Bits 0-3: month (1-12)
    Bits 4-8: day (1-31)
    Bits 9-15: year (0-99)
    static String
    getPascalString(byte[] buffer, int offset)
    Extract a Pascal string from the buffer.
    static Date
    getProdosDate(byte[] buffer, int offset)
    Extract a ProDOS date from the buffer.
    static String
    getProdosString(byte[] buffer, int offset)
    Extract a ProDOS string from the buffer.
    static double
    getSaneNumber(byte[] buffer, int offset)
    Pull a SANE formatted number from the buffer and return it as a Java double datatype.
    static int
    getSignedWordValue(byte[] buffer, int offset)
    Compute the signed value of a word.
    static String
    getString(byte[] buffer, int offset, int length)
    Extract a string from the buffer.
    static int
    getUnsignedByte(byte value)
    Extract out an unsigned byte as an int.
    static int
    getUnsignedByte(byte[] buffer, int offset)
    Extract out an unsigned byte as an int.
    static int
    getWordValue(byte[] buffer, int offset)
    Compute the value of a word.
    static int
    getWordValue(byte low, byte high)
    Compute the value of a word.
    static boolean
    isBitSet(byte byt, int bit)
    Determine if a specific bit is set.
    protected static boolean
    sameBlocksPerDisk(ImageOrder sourceOrder, ImageOrder targetOrder)
    Answers true if the two disks have the same number of blocks per disk.
    protected static boolean
    sameSectorsPerDisk(ImageOrder sourceOrder, ImageOrder targetOrder)
    Answers true if the two disks have the same sectors per disk.
    static void
    set3ByteValue(byte[] buffer, int offset, int value)
    Set the value of a 3 byte value.
    static byte
    setBit(byte byt, int bit)
    Set a specific bit (turn it on).
    static void
    setPascalDate(byte[] buffer, int offset, Date date)
    Set a Pascal data to the buffer.
    Bits 0-3: month (1-12)
    Bits 4-8: day (1-31)
    Bits 9-15: year (0-99)
    static void
    setPascalString(byte[] buffer, int offset, String string, int maxLength)
    Set a Pascal string into the buffer.
    static void
    setProdosDate(byte[] buffer, int offset, Date date)
    Set a ProDOS date into the buffer.
    static void
    setProdosString(byte[] buffer, int offset, String string, int maxLength)
    Sets a ProDOS string into the buffer.
    static void
    setString(byte[] buffer, int offset, String string)
    Create an Apple string that is the same length as the given string.
    static void
    setString(byte[] buffer, int offset, String string, int length)
    Create an Apple string that is space delimited.
    static void
    setString(byte[] buffer, int offset, String string, int length, boolean highBitOn)
    Create an Apple string that is space delimited.
    static void
    setWordValue(byte[] buffer, int offset, int value)
    Set a word value.
    static byte[]
    unpackBytes(byte[] compressedData)
    Mimic the Apple IIGS UnPackBytes method call.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • AppleUtil

      public AppleUtil()

  • Method Details

    • getWordValue

      public static int getWordValue(byte[] buffer, int offset)
      Compute the value of a word. Pulls value from buffer given the offset. A word is two bytes, in standard Apple LO/HI format.

    • getWordValue

      public static int getWordValue(byte low, byte high)
      Compute the value of a word.

    • getSignedWordValue

      public static int getSignedWordValue(byte[] buffer, int offset)
      Compute the signed value of a word.

    • setWordValue

      public static void setWordValue(byte[] buffer, int offset, int value)
      Set a word value.

    • get3ByteValue

      public static int get3ByteValue(byte[] buffer, int offset)
      Compute the value of a 3 byte value. This may be ProDOS specific. Pulls value from buffer given the offset. Stored in standard Apple LO/HI format.

    • getLongValue

      public static long getLongValue(byte[] buffer, int offset)
      Compute the value of a 4 byte value. This is specific to DC42 processing. Pulls value from buffer given the offset, MSB first.

    • set3ByteValue

      public static void set3ByteValue(byte[] buffer, int offset, int value)
      Set the value of a 3 byte value.

    • getUnsignedByte

      public static int getUnsignedByte(byte value)
      Extract out an unsigned byte as an int. All Java bytes are signed; need to convert to an int and remove the sign.

    • getUnsignedByte

      public static int getUnsignedByte(byte[] buffer, int offset)
      Extract out an unsigned byte as an int. All Java bytes are signed; need to convert to an int and remove the sign.

    • getBitCount

      public static int getBitCount(byte byt)
      Count the number of bits set in a byte.

    • isBitSet

      public static boolean isBitSet(byte byt, int bit)
      Determine if a specific bit is set.

    • setBit

      public static byte setBit(byte byt, int bit)
      Set a specific bit (turn it on).

    • clearBit

      public static byte clearBit(byte byt, int bit)
      Clear a specific bit (turn it off).

    • getString

      public static String getString(byte[] buffer, int offset, int length)
      Extract a string from the buffer.

    • setString

      public static void setString(byte[] buffer, int offset, String string, int length)
      Create an Apple string that is space delimited.

    • setString

      public static void setString(byte[] buffer, int offset, String string, int length, boolean highBitOn)
      Create an Apple string that is space delimited.

    • setString

      public static void setString(byte[] buffer, int offset, String string)
      Create an Apple string that is the same length as the given string.

    • getPascalString

      public static String getPascalString(byte[] buffer, int offset)
      Extract a Pascal string from the buffer.

    • setPascalString

      public static void setPascalString(byte[] buffer, int offset, String string, int maxLength)
      Set a Pascal string into the buffer.

    • getPascalDate

      public static Date getPascalDate(byte[] buffer, int offset)
      Extract a Pascal date from the buffer.
      Bits 0-3: month (1-12)
      Bits 4-8: day (1-31)
      Bits 9-15: year (0-99)

    • setPascalDate

      public static void setPascalDate(byte[] buffer, int offset, Date date)
      Set a Pascal data to the buffer.
      Bits 0-3: month (1-12)
      Bits 4-8: day (1-31)
      Bits 9-15: year (0-99)

    • getProdosString

      public static String getProdosString(byte[] buffer, int offset)
      Extract a ProDOS string from the buffer.

    • setProdosString

      public static void setProdosString(byte[] buffer, int offset, String string, int maxLength)
      Sets a ProDOS string into the buffer.

    • getFormattedByte

      public static String getFormattedByte(int byt)
      Format a byte value as hexadecimal.

    • getFormattedWord

      public static String getFormattedWord(int word)
      Format a word value as hexadecimal.

    • getFormatted3ByteAddress

      public static String getFormatted3ByteAddress(int addr)
      Format a 3 byte value as hexadecimal.

    • convertFormattedWord

      public static int convertFormattedWord(String word)
      Convert a typical Apple formatted word. This is essentially a hex string that may start with a '$' and has 1 - 4 digits.

    • getProdosDate

      public static Date getProdosDate(byte[] buffer, int offset)
      Extract a ProDOS date from the buffer.

    • setProdosDate

      public static void setProdosDate(byte[] buffer, int offset, Date date)
      Set a ProDOS date into the buffer.

    • getNiceFilename

      public static String getNiceFilename(String filename)
      Make a "nice" filename. Some of the Apple ][ file names have characters that are unpalatable - such as "/" or "\" or ":" which are directory separators along with other characters that are not allowed by various operating systems. This method just sanitizes the filename.

    • unpackBytes

      public static byte[] unpackBytes(byte[] compressedData)
      Mimic the Apple IIGS UnPackBytes method call. The compression is very similar the RLE, but has the following coding conventions:
      00xx xxxx = 1 to 64 bytes follow (all different)
      01xx xxxx = 3, 5, 6, or 7 repeats of next byte
      10xx xxxx = 1 to 64 repeats of next 4 bytes
      11xx xxxx = 1 to 64 repeats of next byte taken as 4 bytes
      The 6 data bits are stored as length-1; hence 000000 is a length of 1 and 111111 is a length of 64.

    • getSaneNumber

      public static double getSaneNumber(byte[] buffer, int offset)
      Pull a SANE formatted number from the buffer and return it as a Java double datatype. Fortunately, SANE is the IEEE 754 format which _is_ Java's double datatype. The Double class has an intrinsic longBitsToDouble method to do this. The SANE/IEEE 754 format is setup as such: 
         E SSSSSSSSSSS FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF...F
      
   0 1........11 12....................................63
      Where E is the sign bit, S is the exponent bits and F is the fraction bits. The format is discussed within the Double class documentation as around the web. Be aware that the fraction bits are base 2. Meaning that a fraction of .101 is, in reality, a binary fraction. In decimal, this is 1/2 + 0/4 + 1/8 = 5/8 or .625. See http://www.psc.edu/general/software/packages/ieee/ieee.html for an example.

      Note: SANE numbers, as stored by AppleWorks are in typical low/high format.

    • getApplesoftFloat

      public static byte[] getApplesoftFloat(double number)
      Convert a double number to an Applesoft float. This is a 5 byte number. See "Applesoft: Internals" for more details and review the Merlin-generated Applesoft source code.

      Since the number is 5 bytes long, a float will not work - hence the double. Some precision is lost, but (hopefully) nothing significant!

      More specifically, the mapping is as follows:
      (Applesoft)
      EEEEEEEE SFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF
      (IEEE 754 - Java)
      SEEEEEEE EEEEFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF
      The mapping will blank the following Double bits:
      S000EEEE EEEEFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFF0000 00000000 00000000

    • getHexDump

      public static String getHexDump(byte[] bytes)
      Generate a simple hex dump from the given byte array.

      This is in the general form of:
      MMMMMM: HH HH HH HH HH HH HH HH HH HH HH HH HH HH HH HH AAAAAAAA AAAAAAAA
      Where MMMMMM = memory address, HH = hex byte, and A = ASCII character.

    • getHexDump

      public static String getHexDump(int address, byte[] bytes)

    • changeImageOrderByTrackAndSector

      public static void changeImageOrderByTrackAndSector(ImageOrder sourceOrder, ImageOrder targetOrder)
      Change ImageOrder from source order to target order by copying sector by sector.

    • sameSectorsPerDisk

      protected static boolean sameSectorsPerDisk(ImageOrder sourceOrder, ImageOrder targetOrder)
      Answers true if the two disks have the same sectors per disk.

    • changeImageOrderByBlock

      public static void changeImageOrderByBlock(ImageOrder sourceOrder, ImageOrder targetOrder)
      Change ImageOrder from source order to target order by copying block by block.

    • sameBlocksPerDisk

      protected static boolean sameBlocksPerDisk(ImageOrder sourceOrder, ImageOrder targetOrder)
      Answers true if the two disks have the same number of blocks per disk.