de.schlichtherle.util.zip
Class ZipFile

java.lang.Object
  de.schlichtherle.util.zip.BasicZipFile
      de.schlichtherle.util.zip.ZipFile

public class ZipFile
extends BasicZipFile

Drop-in replacement for java.util.zip.ZipFile.

Where the constructors of this class accept a charset parameter, this is used to decode comments and entry names in the ZIP file. However, if an entry has bit 11 set in its General Purpose Bit Flag, then this parameter is ignored and "UTF-8" is used for this entry. This is in accordance to Appendix D of PKWARE's ZIP File Format Specification.

This class is able to skip a preamble like the one found in self extracting archives.

The entries returned by this class are instances of de.schlichtherle.util.zip.ZipEntry instead of java.util.zip.ZipEntry.

Note that there is no getName() method because this method would be meaningless when reading archive data from a ReadOnlyFile.

This class is thread-safe.

Version:

TrueZIP 6.7

Author:

Christian Schlichtherle

See Also:

ZipOutputStream

Field Summary

Fields inherited from class de.schlichtherle.util.zip.BasicZipFile

DEFAULT_CHARSET

Constructor Summary

ZipFile(File file)
Opens the given file for reading its ZIP contents, assuming UTF-8 charset for file names.

ZipFile(File file, String charset)
Opens the given file for reading its ZIP contents, assuming the specified charset for file names.

ZipFile(File file, String charset, boolean preambled, boolean postambled)
Opens the given file for reading its ZIP contents, assuming the specified charset for file names.

ZipFile(ReadOnlyFile rof)
Opens the given read only file for reading its ZIP contents, assuming UTF-8 charset for file names.

ZipFile(ReadOnlyFile rof, String charset)
Opens the given read only file for reading its ZIP contents, assuming the specified charset for file names.

ZipFile(ReadOnlyFile rof, String charset, boolean preambled, boolean postambled)
Opens the given read only file for reading its ZIP contents, assuming the specified charset for file names.

ZipFile(String name)
Opens the given file for reading its ZIP contents, assuming UTF-8 charset for file names.

ZipFile(String name, String charset)
Opens the given file for reading its ZIP contents, assuming the specified charset for file names.

ZipFile(String name, String charset, boolean preambled, boolean postambled)
Opens the given file for reading its ZIP contents, assuming the specified charset for file names.

Method Summary

boolean	busy() Returns true if and only if some input streams are open to read from this ZIP compatible file.
void	close() Closes the file.
Enumeration	entries() Enumerates clones of all entries in this ZIP file.
ZipEntry	getEntry(String name) Returns a clone of the ZipEntry for the given name or null if no entry with that name exists.
protected InputStream	getInputStream(String name, boolean check, boolean inflate) Returns an InputStream for reading the inflated or deflated data of the given entry.
InputStream	getPostambleInputStream() Returns an InputStream to read the postamble of this ZIP compatible file.
InputStream	getPreambleInputStream() Returns an InputStream to read the preamble of this ZIP compatible file.

Methods inherited from class de.schlichtherle.util.zip.BasicZipFile

createReadOnlyFile, createZipEntry, getCharset, getCheckedInputStream, getCheckedInputStream, getComment, getEncoding, getInputStream, getInputStream, getInputStream, getInputStream, getPostambleLength, getPreambleLength, length, offsetsConsiderPreamble, size

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ZipFile

public ZipFile(String name)
        throws NullPointerException,
               FileNotFoundException,
               ZipException,
               IOException

Opens the given file for reading its ZIP contents, assuming UTF-8 charset for file names.

Parameters:

name - Name of the file.

Throws:

NullPointerException - If name is null.

FileNotFoundException - If the file cannot get opened for reading.

ZipException - If the file is not ZIP compatible.

IOException - On any other I/O related issue.

ZipFile

public ZipFile(String name,
               String charset)
        throws NullPointerException,
               UnsupportedEncodingException,
               FileNotFoundException,
               ZipException,
               IOException

Opens the given file for reading its ZIP contents, assuming the specified charset for file names.

Parameters:

name - Name of the file.

charset - The charset to use for comments and entry names.

Throws:

NullPointerException - If name or charset is null.

UnsupportedEncodingException - If charset is not supported by this JVM.

FileNotFoundException - If the file cannot get opened for reading.

ZipException - If the file is not ZIP compatible.

IOException - On any other I/O related issue.

ZipFile

public ZipFile(String name,
               String charset,
               boolean preambled,
               boolean postambled)
        throws NullPointerException,
               UnsupportedEncodingException,
               FileNotFoundException,
               ZipException,
               IOException

Opens the given file for reading its ZIP contents, assuming the specified charset for file names.

Parameters:

name - Name of the file.

charset - The charset to use for comments and entry names.

preambled - If this is true, then the ZIP compatible file may have a preamble. Otherwise, the ZIP compatible file must start with either a Local File Header (LFH) signature or an End Of Central Directory (EOCD) Header, causing this constructor to fail fast if the file is actually a false positive ZIP compatible file, i.e. not compatible to the ZIP File Format Specification. This may be used to read Self Extracting ZIP files (SFX), which usually contain the application code required for extraction in a preamble. This parameter is true by default.

postambled - If this is true, then the ZIP compatible file may have a postamble of arbitrary length. Otherwise, the ZIP compatible file must not have a postamble which exceeds 64KB size, including the End Of Central Directory record (i.e. including the ZIP file comment), causing this constructor to fail fast if the file is actually a false positive ZIP compatible file, i.e. not compatible to the ZIP File Format Specification. This may be used to read Self Extracting ZIP files (SFX) with large postambles. This parameter is false by default.

Throws:

NullPointerException - If name or charset is null.

UnsupportedEncodingException - If charset is not supported by this JVM.

FileNotFoundException - If the file cannot get opened for reading.

ZipException - If the file is not ZIP compatible.

IOException - On any other I/O related issue.

ZipFile

public ZipFile(File file)
        throws NullPointerException,
               FileNotFoundException,
               ZipException,
               IOException

Opens the given file for reading its ZIP contents, assuming UTF-8 charset for file names.

Parameters:

file - The file.

Throws:

NullPointerException - If file is null.

FileNotFoundException - If the file cannot get opened for reading.

ZipException - If the file is not ZIP compatible.

IOException - On any other I/O related issue.

ZipFile

public ZipFile(File file,
               String charset)
        throws NullPointerException,
               UnsupportedEncodingException,
               FileNotFoundException,
               ZipException,
               IOException

Opens the given file for reading its ZIP contents, assuming the specified charset for file names.

Parameters:

file - The file.

charset - The charset to use for comments and entry names.

Throws:

NullPointerException - If file or charset is null.

UnsupportedEncodingException - If charset is not supported by this JVM.

FileNotFoundException - If the file cannot get opened for reading.

ZipException - If the file is not ZIP compatible.

IOException - On any other I/O related issue.

ZipFile

public ZipFile(File file,
               String charset,
               boolean preambled,
               boolean postambled)
        throws NullPointerException,
               UnsupportedEncodingException,
               FileNotFoundException,
               ZipException,
               IOException

Opens the given file for reading its ZIP contents, assuming the specified charset for file names.

Parameters:

file - The file.

charset - The charset to use for comments and entry names.

preambled - If this is true, then the ZIP compatible file may have a preamble. Otherwise, the ZIP compatible file must start with either a Local File Header (LFH) signature or an End Of Central Directory (EOCD) Header, causing this constructor to fail fast if the file is actually a false positive ZIP compatible file, i.e. not compatible to the ZIP File Format Specification. This may be used to read Self Extracting ZIP files (SFX), which usually contain the application code required for extraction in a preamble. This parameter is true by default.

postambled - If this is true, then the ZIP compatible file may have a postamble of arbitrary length. Otherwise, the ZIP compatible file must not have a postamble which exceeds 64KB size, including the End Of Central Directory record (i.e. including the ZIP file comment), causing this constructor to fail fast if the file is actually a false positive ZIP compatible file, i.e. not compatible to the ZIP File Format Specification. This may be used to read Self Extracting ZIP files (SFX) with large postambles. This parameter is false by default.

Throws:

NullPointerException - If file or charset is null.

UnsupportedEncodingException - If charset is not supported by this JVM.

FileNotFoundException - If the file cannot get opened for reading.

ZipException - If the file is not ZIP compatible.

IOException - On any other I/O related issue.

ZipFile

public ZipFile(ReadOnlyFile rof)
        throws NullPointerException,
               FileNotFoundException,
               ZipException,
               IOException

Opens the given read only file for reading its ZIP contents, assuming UTF-8 charset for file names.

Parameters:

rof - The read only file. Note that this constructor never closes this file.

Throws:

NullPointerException - If rof is null.

FileNotFoundException - If the file cannot get opened for reading.

ZipException - If the file is not ZIP compatible.

IOException - On any other I/O related issue.

ZipFile

public ZipFile(ReadOnlyFile rof,
               String charset)
        throws NullPointerException,
               UnsupportedEncodingException,
               FileNotFoundException,
               ZipException,
               IOException

Opens the given read only file for reading its ZIP contents, assuming the specified charset for file names.

Parameters:

rof - The read only file. Note that this constructor never closes this file.

charset - The charset to use for comments and entry names.

Throws:

NullPointerException - If rof or charset is null.

UnsupportedEncodingException - If charset is not supported by this JVM.

FileNotFoundException - If the file cannot get opened for reading.

ZipException - If the file is not ZIP compatible.

IOException - On any other I/O related issue.

ZipFile

public ZipFile(ReadOnlyFile rof,
               String charset,
               boolean preambled,
               boolean postambled)
        throws NullPointerException,
               UnsupportedEncodingException,
               FileNotFoundException,
               ZipException,
               IOException

Opens the given read only file for reading its ZIP contents, assuming the specified charset for file names.

Parameters:

rof - The read only file. Note that this constructor never closes this file.

charset - The charset to use for comments and entry names.

preambled - If this is true, then the ZIP compatible file may have a preamble. Otherwise, the ZIP compatible file must start with either a Local File Header (LFH) signature or an End Of Central Directory (EOCD) Header, causing this constructor to fail fast if the file is actually a false positive ZIP compatible file, i.e. not compatible to the ZIP File Format Specification. This may be used to read Self Extracting ZIP files (SFX), which usually contain the application code required for extraction in a preamble. This parameter is true by default.

postambled - If this is true, then the ZIP compatible file may have a postamble of arbitrary length. Otherwise, the ZIP compatible file must not have a postamble which exceeds 64KB size, including the End Of Central Directory record (i.e. including the ZIP file comment), causing this constructor to fail fast if the file is actually a false positive ZIP compatible file, i.e. not compatible to the ZIP File Format Specification. This may be used to read Self Extracting ZIP files (SFX) with large postambles. This parameter is false by default.

Throws:

NullPointerException - If rof or charset is null.

UnsupportedEncodingException - If charset is not supported by this JVM.

FileNotFoundException - If the file cannot get opened for reading.

ZipException - If the file is not ZIP compatible.

IOException - On any other I/O related issue.

Method Detail

entries

public Enumeration entries()

Enumerates clones of all entries in this ZIP file.

Overrides:

entries in class BasicZipFile

getEntry

public ZipEntry getEntry(String name)

Returns a clone of the ZipEntry for the given name or null if no entry with that name exists.

Overrides:

getEntry in class BasicZipFile

Parameters:

name - Name of the ZIP entry.

getPreambleInputStream

public InputStream getPreambleInputStream()
                                   throws IOException

Description copied from class: BasicZipFile

Returns an InputStream to read the preamble of this ZIP compatible file.

Note that the returned stream is a lightweight stream, i.e. there is no external resource such as a ReadOnlyFile allocated for it. Instead, all streams returned by this method share the underlying ReadOnlyFile of this ZipFile. This allows to close this object (and hence the underlying ReadOnlyFile) without cooperation of the returned streams, which is important if the application wants to work on the underlying file again (e.g. update or delete it).

Overrides:

getPreambleInputStream in class BasicZipFile

Throws:

ZipException - If this ZIP file has been closed.

IOException

getPostambleInputStream

public InputStream getPostambleInputStream()
                                    throws IOException

Description copied from class: BasicZipFile

Returns an InputStream to read the postamble of this ZIP compatible file.

Note that the returned stream is a lightweight stream, i.e. there is no external resource such as a ReadOnlyFile allocated for it. Instead, all streams returned by this method share the underlying ReadOnlyFile of this ZipFile. This allows to close this object (and hence the underlying ReadOnlyFile) without cooperation of the returned streams, which is important if the application wants to work on the underlying file again (e.g. update or delete it).

Overrides:

getPostambleInputStream in class BasicZipFile

Throws:

ZipException - If this ZIP file has been closed.

IOException

busy

public boolean busy()

Description copied from class: BasicZipFile

Returns true if and only if some input streams are open to read from this ZIP compatible file.

Overrides:

busy in class BasicZipFile

getInputStream

protected InputStream getInputStream(String name,
                                     boolean check,
                                     boolean inflate)
                              throws IOException

Description copied from class: BasicZipFile

Returns an InputStream for reading the inflated or deflated data of the given entry.

If the BasicZipFile.close() method is called on this instance, all input streams returned by this method are closed, too.

Overrides:

getInputStream in class BasicZipFile

Parameters:

name - The name of the entry to get the stream for - may not be null!

check - Whether or not the entry's CRC-32 value is checked. If and only if this parameter is true, two additional checks are performed for the ZIP entry:

1. All entry headers are checked to have consistent declarations of the CRC-32 value for the inflated entry data.
2. When calling InputStream.close() on the returned entry stream, the CRC-32 value computed from the inflated entry data is checked against the declared CRC-32 values. This is independent from the inflate parameter.

If any of these checks fail, a CRC32Exception is thrown.

This parameter should be false for most applications, and is the default for the sibling of this class in java.util.zip.ZipFile.

inflate - Whether or not the entry data should be inflated. If false, the entry data is not inflated, even if the entry data is deflated. This parameter should be true for most applications.

Returns:

A stream to read the entry data from or null if the entry does not exist.

Throws:

CRC32Exception - If the declared CRC-32 values of the inflated entry data are inconsistent across the entry headers.

ZipException - If this file is not compatible to the ZIP File Format Specification.

IOException - If the entry cannot get read from this ZipFile.

close

public void close()
           throws IOException

Description copied from class: BasicZipFile

Closes the file. This closes any open input streams reading from this ZIP file.

Overrides:

close in class BasicZipFile

Throws:

IOException - if an error occurs closing the file.