Field Detail

• registry

  private static final Map<Integer,Class<? extends ExtraField>> registry

• WINZIP_AES_ID

  static final int WINZIP_AES_ID

  The Header ID for a WinZip AES Extra Field.

  See Also:

  Constant Field Values

• ZIP64_HEADER_ID

  static final int ZIP64_HEADER_ID

  The Header ID for a ZIP64 Extended Information Extra Field.

  See Also:

  Constant Field Values

Constructor Detail

• ExtraField

  ExtraField()

Method Detail

• create

  static ExtraField create(int headerId)

  A static factory method which creates a new Extra Field based on the given Header ID. The returned Extra Field still requires proper initialization, for example by calling readFrom(byte[], int, int).

  Parameters:

  headerId - An unsigned short integer (two bytes) which indicates the type of the returned Extra Field.

  Returns:

  A new Extra Field

  Throws:

  IllegalArgumentException - If headerID is out of range.

  See Also:

  register(java.lang.Class<? extends de.schlichtherle.truezip.zip.ExtraField>)

• getDataBlock

  final byte[] getDataBlock()

  Returns a protective copy of the Data Block.

  See Also:

  getDataSize()

• getDataSize

  abstract int getDataSize()

  Returns the Data Size of this Extra Field. The Data Size is an unsigned short integer (two bytes) which indicates the length of the Data Block in bytes and does not include its own size in this Extra Field. This property may be initialized by calling readFrom(byte[], int, int).

  Returns:

  The size of the Data Block in bytes or 0 if unknown.

  See Also:

  getDataBlock()

• getHeaderId

  abstract int getHeaderId()

  Returns the Header ID (type) of this Extra Field. The Header ID is an unsigned short integer (two bytes) which must be constant during the life cycle of this object.

• readFrom

  abstract void readFrom(byte[] data,
              int off,
              int size)

  Initializes this Extra Field by deserializing a Data Block of size bytes from the byte array data at the zero based offset off. Upon return, this Extra Field shall not access data subsequently and getDataSize() must equal size.

  Parameters:

  data - The byte array to read the Data Block from.

  off - The zero based offset in the byte array where the first byte of the Data Block is read from.

  size - The length of the Data Block in bytes.

  Throws:

  IndexOutOfBoundsException - If the byte array data does not hold at least size bytes at the zero based offset off.

  RuntimeException - If size is illegal or the deserialized Data Block contains illegal data.

  See Also:

  getDataSize()

• register

  static void register(Class<? extends ExtraField> c)

  Registers a concrete implementation of this abstract base class for use with the static factory method create(int).

  Parameters:

  c - the implementation class of this abstract base class.

  Throws:

  IllegalArgumentException - if c cannot get instantiated, is not a subclass of ExtraField or its Header ID is out of range. A more descriptive exception may be associated to it as its cause.

  See Also:

  create(int)

• writeTo

  abstract void writeTo(byte[] data,
             int off)

  Serializes a Data Block of getDataSize() bytes to the byte array data at the zero based offset off. Upon return, this Extra Field shall not access data subsequently.

  Parameters:

  data - The byte array to write the Data Block to.

  off - The zero based offset in the byte array where the first byte of the Data Block is written to.

  Throws:

  IndexOutOfBoundsException - If the byte array data does not hold at least getDataSize() bytes at the zero based offset off.

  See Also:

  getDataSize()