java.util.zip (Java Platform SE 8 )
Keywords: java.util.zip package
Date: 2026-04-24

compact3

# Package java.util.zip

Provides classes for reading and writing the standard ZIP and GZIP file formats.

See: Description

- Interface Summary
  Interface | Description
  --- | ---
  Checksum | An interface representing a data checksum.

- Class Summary
  Class | Description
  --- | ---
  Adler32 | A class that can be used to compute the Adler-32 checksum of a data stream.
  CheckedInputStream | An input stream that also maintains a checksum of the data being read.
  CheckedOutputStream | An output stream that also maintains a checksum of the data being written.
  CRC32 | A class that can be used to compute the CRC-32 of a data stream.
  Deflater | This class provides support for general purpose compression using the popular ZLIB compression library.
  DeflaterInputStream | Implements an input stream filter for compressing data in the "deflate" compression format.
  DeflaterOutputStream | This class implements an output stream filter for compressing data in the "deflate" compression format.
  GZIPInputStream | This class implements a stream filter for reading compressed data in the GZIP file format.
  GZIPOutputStream | This class implements a stream filter for writing compressed data in the GZIP file format.
  Inflater | This class provides support for general purpose decompression using the popular ZLIB compression library.
  InflaterInputStream | This class implements a stream filter for uncompressing data in the "deflate" compression format.
  InflaterOutputStream | Implements an output stream filter for uncompressing data stored in the "deflate" compression format.
  ZipEntry | This class is used to represent a ZIP file entry.
  ZipFile | This class is used to read entries from a zip file.
  ZipInputStream | This class implements an input stream filter for reading files in the ZIP file format.
  ZipOutputStream | This class implements an output stream filter for writing files in the ZIP file format.

- Exception Summary
  Exception | Description
  --- | ---
  DataFormatException | Signals that a data format error has occurred.
  ZipException | Signals that a Zip exception of some sort has occurred.

- Error Summary
  Error | Description
  --- | ---
  ZipError | Signals that an unrecoverable error has occurred.

## Package java.util.zip Description

Provides classes for reading and writing the standard ZIP and GZIP file formats. Also includes classes for compressing and decompressing data using the DEFLATE compression algorithm, which is used by the ZIP and GZIP file formats. Additionally, there are utility classes for computing the CRC-32 and Adler-32 checksums of arbitrary input streams.

## Package Specification

- Info-ZIP Application Note 970311 - a detailed description of the Info-ZIP format upon which the `java.util.zip` classes are based.

- An implementation may optionally support the ZIP64(tm) format extensions defined by the PKWARE ZIP File Format Specification. The ZIP64(tm) format extensions are used to overcome the size limitations of the original ZIP format.

- APPENDIX D of PKWARE ZIP File Format Specification - Language Encoding Flag (EFS) to encode ZIP entry filename and comment fields using UTF-8.

- ZLIB Compressed Data Format Specification version 3.3 (pdf) (RFC 1950)

- DEFLATE Compressed Data Format Specification version 1.3 (pdf) (RFC 1951)

- GZIP file format specification version 4.3 (pdf) (RFC 1952)

- CRC-32 checksum is described in RFC 1952 (above)

- Adler-32 checksum is described in RFC 1950 (above)

Since:
  JDK1.1

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