ERXMacBinarySwissArmyKnife (Project Wonder Reference Documentation)

java.lang.Object
- er.extensions.components.ERXMacBinarySwissArmyKnife

```
public class ERXMacBinarySwissArmyKnife
extends Object
```
Useful for extracting files from binhexed files, ie when a Mac user uploads a file.

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`_AT` Offsets in header where the fields are located.
`static int`	`CRC_AT` Offsets in header where the fields are located.
`static int`	`FILE_CREATOR_AT` Offsets in header where the fields are located.
`static int`	`FILE_TYPE_AT` Offsets in header where the fields are located.
`static int`	`FINDER_FLAGS1_AT` Offsets in header where the fields are located.
`static int`	`FINDER_FLAGS2_AT` Offsets in header where the fields are located.
`static int`	`FINDER_FLAGS3_AT` Offsets in header where the fields are located.
`static int`	`FINDER_HORZ_AT` Offsets in header where the fields are located.
`static int`	`FINDER_VERT_AT` Offsets in header where the fields are located.
`static int`	`FINDER_WINDOW_AT` Offsets in header where the fields are located.
`static int`	`FLAG_LOCKED_AT` Offsets in header where the fields are located.
`static int`	`LEN_COMMENT_AT` Offsets in header where the fields are located.
`static int`	`LEN_DATA_FORK_AT` Offsets in header where the fields are located.
`static int`	`LEN_RES_FORK_AT` Offsets in header where the fields are located.
`static int`	`LEN_SECONDARY_AT` Offsets in header where the fields are located.
`protected static int[]`	`levelMasks` Bit-masks for different levels.
`static long`	`LIMIT_DATAFORK` Enforce this limit on data-fork length, due either to Mac OS API or field-width.
`static int`	`LIMIT_NAME` Enforce this limit on name-length, regardless of available space in header.
`static int`	`LIMIT_RESFORK` Enforce this limit on resource-fork length, due either to Mac OS API or field-width.
`static int`	`MACBINARY_HEADER_LEN` Length of a MacBinary header, always the first component of the file, and the only required element.
`static int`	`MB1_VERSION` Possible values in VERSION_TARGET_AT and VERSION_MIN_AT byte-sized fields.
`static int`	`MB2_VERSION` Possible values in VERSION_TARGET_AT and VERSION_MIN_AT byte-sized fields.
`static int`	`MB3_SIGNATURE` Distinctive int-sized value in MB3_SIGNATURE_AT field, only present for MB-3 format.
`static int`	`MB3_SIGNATURE_AT` Offsets in header where the fields are located.
`static int`	`MB3_VERSION` Possible values in VERSION_TARGET_AT and VERSION_MIN_AT byte-sized fields.
`static int`	`NAME_BYTES_AT` Offsets in header where the fields are located.
`static int`	`NAME_LEN_AT` Offsets in header where the fields are located.
`static int`	`NAME_SCRIPT_AT` Offsets in header where the fields are located.
`protected static boolean`	`strict`
`static int`	`VERSION_MIN_AT` Offsets in header where the fields are located.
`static int`	`VERSION_OBSOLETE_AT` Offsets in header where the fields are located.
`static int`	`VERSION_TARGET_AT` Offsets in header where the fields are located.
`static int`	`WHEN_CREATED_AT` Offsets in header where the fields are located.
`static int`	`WHEN_MODIFIED_AT` Offsets in header where the fields are located.
`static int`	`ZERO_1_AT` Offsets in header where the fields are located.
`static int`	`ZERO_2_AT` Offsets in header where the fields are located.
`static int`	`ZERO_3_AT` Offsets in header where the fields are located.

Constructor Summary

Constructors
Constructor and Description

ERXMacBinarySwissArmyKnife()

ERXMacBinarySwissArmyKnife(NSData fileData)

Constructors
Constructor and Description
`ERXMacBinarySwissArmyKnife()`
`ERXMacBinarySwissArmyKnife(NSData fileData)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`int`	`calcCRC()` Calculate and return a CRC over the header.
`int`	`calcCRC2()` Calculate and return an alternative header CRC.
`static int`	`calculateCRC(int seed, byte[] bytes, int offset, int count)` Calculate a MacBinary CRC using the given starting seed, and proceeding over the given range of bytes.
`int`	`checkFormat(boolean strictFormat)`
`byte[]`	`getByteArray()` Get the internal byte-array.
`byte`	`getByteAt(int offset)` Return the signed byte at the given offset.
`int`	`getCRC()` Return the header CRC, as embedded in the header itself.
`int`	`getDataForkLength()` Get the data-fork length from the header.
`int`	`getIntAt(int offset)` Return the signed int at the given offset.
`long`	`getLongAt(int offset)` Return the signed long at the given offset.
`int`	`getResourceForkLength()` Get the resource-fork length from the header.
`short`	`getShortAt(int offset)` Return the signed short at the given offset.
`int`	`getUByteAt(int offset)` Return an int holding the unsigned byte at the given offset.
`long`	`getUIntAt(int offset)` Return a long holding the unsigned int at the given offset.
`int`	`getUShortAt(int offset)` Return an int holding the unsigned short at the given offset.
`boolean`	`isMacBinary(NSData fileData)`
`boolean`	`isValidCRC()` Calculate and check the header CRC.
`void`	`putByteAt(byte value, int offset)` Put the given byte at the supplied offset.
`void`	`putBytesAt(byte[] data, int offset)` Put all the given bytes at the supplied offset.
`void`	`putBytesAt(byte[] data, int offset, int count)` Put the given bytes at the supplied offset.
`void`	`putIntAt(int value, int offset)` Put the given int at the supplied offset.
`void`	`putLongAt(long value, int offset)` Put the given long at the supplied offset.
`void`	`putShortAt(short value, int offset)` Put the given short at the supplied offset.
`void`	`setByteArray(byte[] bytes)` Use the given array to hold bytes.
`void`	`setCRC()` Calculate and set the CRC over the header bytes previously set, invoking calcCRC() to calculate the 16-bit value to store.
`NSData`	`unwrapMacBinary(NSData fileContents)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - ZERO_1_AT
```
public static final int ZERO_1_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - NAME_LEN_AT
```
public static final int NAME_LEN_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - NAME_BYTES_AT
```
public static final int NAME_BYTES_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - FILE_TYPE_AT
```
public static final int FILE_TYPE_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - FILE_CREATOR_AT
```
public static final int FILE_CREATOR_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - FINDER_FLAGS1_AT
```
public static final int FINDER_FLAGS1_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - ZERO_2_AT
```
public static final int ZERO_2_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - FINDER_VERT_AT
```
public static final int FINDER_VERT_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - FINDER_HORZ_AT
```
public static final int FINDER_HORZ_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - FINDER_WINDOW_AT
```
public static final int FINDER_WINDOW_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - FLAG_LOCKED_AT
```
public static final int FLAG_LOCKED_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - ZERO_3_AT
```
public static final int ZERO_3_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - LEN_DATA_FORK_AT
```
public static final int LEN_DATA_FORK_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - LEN_RES_FORK_AT
```
public static final int LEN_RES_FORK_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - WHEN_CREATED_AT
```
public static final int WHEN_CREATED_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - WHEN_MODIFIED_AT
```
public static final int WHEN_MODIFIED_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - LEN_COMMENT_AT
```
public static final int LEN_COMMENT_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - FINDER_FLAGS2_AT
```
public static final int FINDER_FLAGS2_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - MB3_SIGNATURE_AT
```
public static final int MB3_SIGNATURE_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - NAME_SCRIPT_AT
```
public static final int NAME_SCRIPT_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - FINDER_FLAGS3_AT
```
public static final int FINDER_FLAGS3_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - LEN_SECONDARY_AT
```
public static final int LEN_SECONDARY_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - VERSION_TARGET_AT
```
public static final int VERSION_TARGET_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - VERSION_MIN_AT
```
public static final int VERSION_MIN_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - CRC_AT
```
public static final int CRC_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - VERSION_OBSOLETE_AT
```
public static final int VERSION_OBSOLETE_AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - _AT
```
public static final int _AT
```
    Offsets in header where the fields are located.
    
    See Also:
    
    Constant Field Values
  - MB1_VERSION
```
public static final int MB1_VERSION
```
    Possible values in VERSION_TARGET_AT and VERSION_MIN_AT byte-sized fields.
    
    See Also:
    
    Constant Field Values
  - MB2_VERSION
```
public static final int MB2_VERSION
```
    Possible values in VERSION_TARGET_AT and VERSION_MIN_AT byte-sized fields.
    
    See Also:
    
    Constant Field Values
  - MB3_VERSION
```
public static final int MB3_VERSION
```
    Possible values in VERSION_TARGET_AT and VERSION_MIN_AT byte-sized fields.
    
    See Also:
    
    Constant Field Values
  - MB3_SIGNATURE
```
public static final int MB3_SIGNATURE
```
    Distinctive int-sized value in MB3_SIGNATURE_AT field, only present for MB-3 format.
    
    See Also:
    
    Constant Field Values
  - levelMasks
```
protected static final int[] levelMasks
```
    Bit-masks for different levels. The mask at 0 clears only the "do not restore" flags, but none of the "reserved" bits. "Reserved" bits are cleared to zero in the other masks -- you may not want
  - MACBINARY_HEADER_LEN
```
public static final int MACBINARY_HEADER_LEN
```
    Length of a MacBinary header, always the first component of the file, and the only required element. A MacBinary file must be at least this length.
    
    See Also:
    
    Constant Field Values
  - LIMIT_DATAFORK
```
public static final long LIMIT_DATAFORK
```
    Enforce this limit on data-fork length, due either to Mac OS API or field-width.
    
    See Also:
    
    Constant Field Values
  - LIMIT_RESFORK
```
public static final int LIMIT_RESFORK
```
    Enforce this limit on resource-fork length, due either to Mac OS API or field-width.
    
    See Also:
    
    Constant Field Values
  - LIMIT_NAME
```
public static final int LIMIT_NAME
```
    Enforce this limit on name-length, regardless of available space in header.
    
    See Also:
    
    Constant Field Values
  - strict
```
protected static boolean strict
```
- Constructor Detail
  - ERXMacBinarySwissArmyKnife
```
public ERXMacBinarySwissArmyKnife()
```
  - ERXMacBinarySwissArmyKnife
```
public ERXMacBinarySwissArmyKnife(NSData fileData)
```
- Method Detail
  - isMacBinary
```
public boolean isMacBinary(NSData fileData)
```
  - unwrapMacBinary
```
public NSData unwrapMacBinary(NSData fileContents)
```
  - checkFormat
```
public int checkFormat(boolean strictFormat)
```
  - getByteAt
```
public byte getByteAt(int offset)
```
    Return the signed byte at the given offset.
  - getUByteAt
```
public int getUByteAt(int offset)
```
    Return an int holding the unsigned byte at the given offset.
  - getShortAt
```
public short getShortAt(int offset)
```
    Return the signed short at the given offset.
  - getUShortAt
```
public int getUShortAt(int offset)
```
    Return an int holding the unsigned short at the given offset.
  - getIntAt
```
public int getIntAt(int offset)
```
    Return the signed int at the given offset.
  - getUIntAt
```
public long getUIntAt(int offset)
```
    Return a long holding the unsigned int at the given offset.
  - getLongAt
```
public long getLongAt(int offset)
```
    Return the signed long at the given offset.
  - putByteAt
```
public void putByteAt(byte value,
                      int offset)
```
    Put the given byte at the supplied offset.
  - putBytesAt
```
public void putBytesAt(byte[] data,
                       int offset)
```
    Put all the given bytes at the supplied offset.
  - putBytesAt
```
public void putBytesAt(byte[] data,
                       int offset,
                       int count)
```
    Put the given bytes at the supplied offset.
  - putShortAt
```
public void putShortAt(short value,
                       int offset)
```
    Put the given short at the supplied offset.
  - putIntAt
```
public void putIntAt(int value,
                     int offset)
```
    Put the given int at the supplied offset.
  - putLongAt
```
public void putLongAt(long value,
                      int offset)
```
    Put the given long at the supplied offset.
  - getByteArray
```
public final byte[] getByteArray()
```
    Get the internal byte-array.
  - setByteArray
```
public final void setByteArray(byte[] bytes)
```
    Use the given array to hold bytes. Accepts null and/or zero-length arrays without error, though a subsequent get or put will throw an exception.
  - getDataForkLength
```
public int getDataForkLength()
```
    Get the data-fork length from the header.
  - getResourceForkLength
```
public int getResourceForkLength()
```
    Get the resource-fork length from the header.
  - calculateCRC
```
public static int calculateCRC(int seed,
                               byte[] bytes,
                               int offset,
                               int count)
```
    Calculate a MacBinary CRC using the given starting seed, and proceeding over the given range of bytes. The returned CRC value is a 16-bit result in an int, because it's unsigned.
  - setCRC
```
public void setCRC()
```
    Calculate and set the CRC over the header bytes previously set, invoking calcCRC() to calculate the 16-bit value to store. You should only invoke this after setting every other field of interest, such as name and name-encoding, data-fork len, res-fork len, secondary-header len, etc. Since the CRC is calculated internally, there is no parameter to this method, even though it's a "setter" method.
    In most cases, you will find finishHeader() more useful since it finishes all the assembly for a particular header-format you select.
  - isValidCRC
```
public boolean isValidCRC()
```
    Calculate and check the header CRC.
  - calcCRC
```
public int calcCRC()
```
    Calculate and return a CRC over the header. The CRC value is in the low 16-bits of the returned int.
  - calcCRC2
```
public int calcCRC2()
```
    Calculate and return an alternative header CRC. Where calcCRC() calculates over the first 124 bytes of the header, this calculates over the first 126 bytes of the header. I'm guessing that with a valid CRC-value in the header, the returned value is zero, but I don't know enough about CRC theory and practice to assert that confidently. This is more of a Greg's-hacky-toy than anything that might actually be useful.
  - getCRC
```
public int getCRC()
```
    Return the header CRC, as embedded in the header itself.

Class ERXMacBinarySwissArmyKnife

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

ZERO_1_AT

NAME_LEN_AT

NAME_BYTES_AT

FILE_TYPE_AT

FILE_CREATOR_AT

FINDER_FLAGS1_AT

ZERO_2_AT

FINDER_VERT_AT

FINDER_HORZ_AT

FINDER_WINDOW_AT

FLAG_LOCKED_AT

ZERO_3_AT

LEN_DATA_FORK_AT

LEN_RES_FORK_AT

WHEN_CREATED_AT

WHEN_MODIFIED_AT

LEN_COMMENT_AT

FINDER_FLAGS2_AT

MB3_SIGNATURE_AT

NAME_SCRIPT_AT

FINDER_FLAGS3_AT

LEN_SECONDARY_AT

VERSION_TARGET_AT

VERSION_MIN_AT

CRC_AT

VERSION_OBSOLETE_AT

_AT

MB1_VERSION

MB2_VERSION

MB3_VERSION

MB3_SIGNATURE

levelMasks

MACBINARY_HEADER_LEN

LIMIT_DATAFORK

LIMIT_RESFORK

LIMIT_NAME

strict

Constructor Detail

ERXMacBinarySwissArmyKnife

ERXMacBinarySwissArmyKnife

Method Detail

isMacBinary

unwrapMacBinary

checkFormat

getByteAt

getUByteAt

getShortAt

getUShortAt

getIntAt

getUIntAt

getLongAt

putByteAt

putBytesAt

putBytesAt

putShortAt

putIntAt

putLongAt

getByteArray

setByteArray

getDataForkLength

getResourceForkLength

calculateCRC

setCRC

isValidCRC

calcCRC

calcCRC2

getCRC