## org.apache.tools.zip
Interface ZipExtraField

All Known Implementing Classes:
  AsiExtraField, JarMarker, UnrecognizedExtraField

    public interface ZipExtraField

General format of extra field data.

Extra fields usually appear twice per file, once in the local file data and once in the central directory. Usually they are the same, but they don't have to be. `java.util.zip.ZipOutputStream` will only use the local file data in both places.

Method Summary
`byte[]` `getCentralDirectoryData()` The actual data to put central directory - without Header-ID or length specifier.
`ZipShort` `getCentralDirectoryLength()` Length of the extra field in the central directory - without Header-ID or length specifier.
`ZipShort` `getHeaderId()` The Header-ID.
`byte[]` `getLocalFileDataData()` The actual data to put into local file data - without Header-ID or length specifier.
`ZipShort` `getLocalFileDataLength()` Length of the extra field in the local file data - without Header-ID or length specifier.
`void` `parseFromLocalFileData(byte[] data, int offset, int length)` Populate data from this array as if it was in local file data.

Method Detail

### getHeaderId

    ZipShort getHeaderId()

  The Header-ID.

  Returns:
    the header id
  Since:
    1.1

### getLocalFileDataLength

    ZipShort getLocalFileDataLength()

  Length of the extra field in the local file data - without Header-ID or length specifier.

  Returns:
    the length of the field in the local file data
  Since:
    1.1

### getCentralDirectoryLength

    ZipShort getCentralDirectoryLength()

  Length of the extra field in the central directory - without Header-ID or length specifier.

  Returns:
    the length of the field in the central directory
  Since:
    1.1

### getLocalFileDataData

    byte[] getLocalFileDataData()

  The actual data to put into local file data - without Header-ID or length specifier.

  Returns:
    the data
  Since:
    1.1

### getCentralDirectoryData

    byte[] getCentralDirectoryData()

  The actual data to put central directory - without Header-ID or length specifier.

  Returns:
    the data
  Since:
    1.1

### parseFromLocalFileData

    void parseFromLocalFileData(byte[] data,
                                int offset,
                                int length)
                                throws java.util.zip.ZipException

  Populate data from this array as if it was in local file data.

  Parameters:
    `data` - an array of bytes
    `offset` - the start offset
    `length` - the number of bytes in the array from offset
  Throws:
    `java.util.zip.ZipException` - on error
  Since:
    1.1