Package org.apache.tools.zip

# Interface ZipExtraField

All Known Subinterfaces:
  `CentralDirectoryParsingZipExtraField`

All Known Implementing Classes:
  `AbstractUnicodeExtraField`, `AsiExtraField`, `JarMarker`, `UnicodeCommentExtraField`, `UnicodePathExtraField`, `UnparseableExtraFieldData`, `UnrecognizedExtraField`, `Zip64ExtendedInformationExtraField`

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

Modifier and Type
Method
Description
`byte[]`
`getCentralDirectoryData()`
The actual data to put into 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 Details

### 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 into central directory - without Header-ID or length specifier.

Returns:
  the data
Since:
  1.1

### parseFromLocalFileData

void parseFromLocalFileData(byte[] data, int offset, int length) throws 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:
  `ZipException` - on error
Since:
  1.1