Class ZipFile

All Implemented Interfaces:
Closeable, AutoCloseable
Direct Known Subclasses:
JarFile
public class ZipFile
extends Object
implements Closeable

This class is used to read entries from a zip file.

Unless otherwise noted, passing a null argument to a constructor or method in this class will cause a NullPointerException to be thrown.

API Note:
To release resources used by this ZipFile, the close() method should be called explicitly or by try-with-resources. Subclasses are responsible for the cleanup of resources acquired by the subclass. Subclasses that override finalize() in order to perform cleanup should be modified to use alternative cleanup mechanisms such as Cleaner and remove the overriding finalize method.
Implementation Requirements:
If this ZipFile has been subclassed and the close method has been overridden, the close method will be called by the finalization when ZipFile is unreachable. But the subclasses should not depend on this specific implementation; the finalization is not reliable and the finalize method is deprecated to be removed.
Since:
1.1

Field Summary

Fields
Modifier and Type Field Description
static int CENATT
static int CENATX
static int CENCOM
static int CENCRC
static int CENDSK
static int CENEXT
static int CENFLG
static int CENHDR
static int CENHOW
static int CENLEN
static int CENNAM
static int CENOFF
static long CENSIG
static int CENSIZ
static int CENTIM
static int CENVEM
static int CENVER
static int ENDCOM
static int ENDHDR
static int ENDOFF
static long ENDSIG
static int ENDSIZ
static int ENDSUB
static int ENDTOT
static int EXTCRC
static int EXTHDR
static int EXTLEN
static long EXTSIG
static int EXTSIZ
static int LOCCRC
static int LOCEXT
static int LOCFLG
static int LOCHDR
static int LOCHOW
static int LOCLEN
static int LOCNAM
static long LOCSIG
static int LOCSIZ
static int LOCTIM
static int LOCVER
static int OPEN_DELETE

Mode flag to open a zip file and mark it for deletion.

static int OPEN_READ

Mode flag to open a zip file for reading.

Constructor Summary

Constructors
Constructor Description
ZipFile​(File file)

Opens a ZIP file for reading given the specified File object.

ZipFile​(File file, int mode)

Opens a new ZipFile to read from the specified File object in the specified mode.

ZipFile​(File file, int mode, Charset charset)

Opens a new ZipFile to read from the specified File object in the specified mode.

ZipFile​(File file, Charset charset)

Opens a ZIP file for reading given the specified File object.

ZipFile​(String name)

Opens a zip file for reading.

ZipFile​(String name, Charset charset)

Opens a zip file for reading.

Method Summary

All Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type Method Description
void close()

Closes the ZIP file.

Enumeration<? extends ZipEntry> entries()

Returns an enumeration of the ZIP file entries.

protected void finalize()

Deprecated, for removal: This API element is subject to removal in a future version.

The finalize method has been deprecated and will be removed.
String getComment()

Returns the zip file comment, or null if none.

ZipEntry getEntry​(String name)

Returns the zip file entry for the specified name, or null if not found.

InputStream getInputStream​(ZipEntry entry)

Returns an input stream for reading the contents of the specified zip file entry.

String getName()

Returns the path name of the ZIP file.

int size()

Returns the number of entries in the ZIP file.

Stream<? extends ZipEntry> stream()

Returns an ordered Stream over the ZIP file entries.

Methods declared in class java.lang.Object

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

Field Detail

OPEN_READ

public static final int OPEN_READ

Mode flag to open a zip file for reading.

See Also:
Constant Field Values

OPEN_DELETE

public static final int OPEN_DELETE

Mode flag to open a zip file and mark it for deletion. The file will be deleted some time between the moment that it is opened and the moment that it is closed, but its contents will remain accessible via the ZipFile object until either the close method is invoked or the virtual machine exits.

See Also:
Constant Field Values

LOCSIG

public static final long LOCSIG
See Also:
Constant Field Values

EXTSIG

public static final long EXTSIG
See Also:
Constant Field Values

CENSIG

public static final long CENSIG
See Also:
Constant Field Values

ENDSIG

public static final long ENDSIG
See Also:
Constant Field Values

LOCHDR

public static final int LOCHDR
See Also:
Constant Field Values

EXTHDR

public static final int EXTHDR
See Also:
Constant Field Values

CENHDR

public static final int CENHDR
See Also:
Constant Field Values

ENDHDR

public static final int ENDHDR
See Also:
Constant Field Values

LOCVER

public static final int LOCVER
See Also:
Constant Field Values

LOCFLG

public static final int LOCFLG
See Also:
Constant Field Values

LOCHOW

public static final int LOCHOW
See Also:
Constant Field Values

LOCTIM

public static final int LOCTIM
See Also:
Constant Field Values

LOCCRC

public static final int LOCCRC
See Also:
Constant Field Values

LOCSIZ

public static final int LOCSIZ
See Also:
Constant Field Values

LOCLEN

public static final int LOCLEN
See Also:
Constant Field Values

LOCNAM

public static final int LOCNAM
See Also:
Constant Field Values

LOCEXT

public static final int LOCEXT
See Also:
Constant Field Values

EXTCRC

public static final int EXTCRC
See Also:
Constant Field Values

EXTSIZ

public static final int EXTSIZ
See Also:
Constant Field Values

EXTLEN

public static final int EXTLEN
See Also:
Constant Field Values

CENVEM

public static final int CENVEM
See Also:
Constant Field Values

CENVER

public static final int CENVER
See Also:
Constant Field Values

CENFLG

public static final int CENFLG
See Also:
Constant Field Values

CENHOW

public static final int CENHOW
See Also:
Constant Field Values

CENTIM

public static final int CENTIM
See Also:
Constant Field Values

CENCRC

public static final int CENCRC
See Also:
Constant Field Values

CENSIZ

public static final int CENSIZ
See Also:
Constant Field Values

CENLEN

public static final int CENLEN
See Also:
Constant Field Values

CENNAM

public static final int CENNAM
See Also:
Constant Field Values

CENEXT

public static final int CENEXT
See Also:
Constant Field Values

CENCOM

public static final int CENCOM
See Also:
Constant Field Values

CENDSK

public static final int CENDSK
See Also:
Constant Field Values

CENATT

public static final int CENATT
See Also:
Constant Field Values

CENATX

public static final int CENATX
See Also:
Constant Field Values

CENOFF

public static final int CENOFF
See Also:
Constant Field Values

ENDSUB

public static final int ENDSUB
See Also:
Constant Field Values

ENDTOT

public static final int ENDTOT
See Also:
Constant Field Values

ENDSIZ

public static final int ENDSIZ
See Also:
Constant Field Values

ENDOFF

public static final int ENDOFF
See Also:
Constant Field Values

ENDCOM

public static final int ENDCOM
See Also:
Constant Field Values

Constructor Detail

ZipFile

public ZipFile​(String name)
        throws IOException

Opens a zip file for reading.

First, if there is a security manager, its checkRead method is called with the name argument as its argument to ensure the read is allowed.

The UTF-8 charset is used to decode the entry names and comments.

Parameters:
name - the name of the zip file
Throws:
ZipException - if a ZIP format error has occurred
IOException - if an I/O error has occurred
SecurityException - if a security manager exists and its checkRead method doesn't allow read access to the file.
See Also:
SecurityManager.checkRead(java.lang.String)

ZipFile

public ZipFile​(File file,
               int mode)
        throws IOException

Opens a new ZipFile to read from the specified File object in the specified mode. The mode argument must be either OPEN_READ or OPEN_READ | OPEN_DELETE.

First, if there is a security manager, its checkRead method is called with the name argument as its argument to ensure the read is allowed.

The UTF-8 charset is used to decode the entry names and comments

Parameters:
file - the ZIP file to be opened for reading
mode - the mode in which the file is to be opened
Throws:
ZipException - if a ZIP format error has occurred
IOException - if an I/O error has occurred
SecurityException - if a security manager exists and its checkRead method doesn't allow read access to the file, or its checkDelete method doesn't allow deleting the file when the OPEN_DELETE flag is set.
IllegalArgumentException - if the mode argument is invalid
Since:
1.3
See Also:
SecurityManager.checkRead(java.lang.String)

ZipFile

public ZipFile​(File file)
        throws ZipException,
               IOException

Opens a ZIP file for reading given the specified File object.

The UTF-8 charset is used to decode the entry names and comments.

Parameters:
file - the ZIP file to be opened for reading
Throws:
ZipException - if a ZIP format error has occurred
IOException - if an I/O error has occurred

ZipFile

public ZipFile​(File file,
               int mode,
               Charset charset)
        throws IOException

Opens a new ZipFile to read from the specified File object in the specified mode. The mode argument must be either OPEN_READ or OPEN_READ | OPEN_DELETE.

First, if there is a security manager, its checkRead method is called with the name argument as its argument to ensure the read is allowed.

Parameters:
file - the ZIP file to be opened for reading
mode - the mode in which the file is to be opened
charset - the charset to be used to decode the ZIP entry name and comment that are not encoded by using UTF-8 encoding (indicated by entry's general purpose flag).
Throws:
ZipException - if a ZIP format error has occurred
IOException - if an I/O error has occurred
SecurityException - if a security manager exists and its checkRead method doesn't allow read access to the file,or its checkDelete method doesn't allow deleting the file when the OPEN_DELETE flag is set
IllegalArgumentException - if the mode argument is invalid
Since:
1.7
See Also:
SecurityManager.checkRead(java.lang.String)

ZipFile

public ZipFile​(String name,
               Charset charset)
        throws IOException

Opens a zip file for reading.

First, if there is a security manager, its checkRead method is called with the name argument as its argument to ensure the read is allowed.

Parameters:
name - the name of the zip file
charset - the charset to be used to decode the ZIP entry name and comment that are not encoded by using UTF-8 encoding (indicated by entry's general purpose flag).
Throws:
ZipException - if a ZIP format error has occurred
IOException - if an I/O error has occurred
SecurityException - if a security manager exists and its checkRead method doesn't allow read access to the file
Since:
1.7
See Also:
SecurityManager.checkRead(java.lang.String)

ZipFile

public ZipFile​(File file,
               Charset charset)
        throws IOException

Opens a ZIP file for reading given the specified File object.

Parameters:
file - the ZIP file to be opened for reading
charset - The charset to be used to decode the ZIP entry name and comment (ignored if the language encoding bit of the ZIP entry's general purpose bit flag is set).
Throws:
ZipException - if a ZIP format error has occurred
IOException - if an I/O error has occurred
Since:
1.7

Method Detail

getComment

public String getComment()

Returns the zip file comment, or null if none.

Returns:
the comment string for the zip file, or null if none
Throws:
IllegalStateException - if the zip file has been closed
Since:
1.7

getEntry

public ZipEntry getEntry​(String name)

Returns the zip file entry for the specified name, or null if not found.

Parameters:
name - the name of the entry
Returns:
the zip file entry, or null if not found
Throws:
IllegalStateException - if the zip file has been closed

getInputStream

public InputStream getInputStream​(ZipEntry entry)
                           throws IOException

Returns an input stream for reading the contents of the specified zip file entry.

Closing this ZIP file will, in turn, close all input streams that have been returned by invocations of this method.

Parameters:
entry - the zip file entry
Returns:
the input stream for reading the contents of the specified zip file entry.
Throws:
ZipException - if a ZIP format error has occurred
IOException - if an I/O error has occurred
IllegalStateException - if the zip file has been closed

getName

public String getName()

Returns the path name of the ZIP file.

Returns:
the path name of the ZIP file

entries

public Enumeration<? extends ZipEntry> entries()

Returns an enumeration of the ZIP file entries.

Returns:
an enumeration of the ZIP file entries
Throws:
IllegalStateException - if the zip file has been closed

stream

public Stream<? extends ZipEntry> stream()

Returns an ordered Stream over the ZIP file entries. Entries appear in the Stream in the order they appear in the central directory of the ZIP file.

Returns:
an ordered Stream of entries in this ZIP file
Throws:
IllegalStateException - if the zip file has been closed
Since:
1.8

size

public int size()

Returns the number of entries in the ZIP file.

Returns:
the number of entries in the ZIP file
Throws:
IllegalStateException - if the zip file has been closed

close

public void close()
           throws IOException

Closes the ZIP file.

Closing this ZIP file will close all of the input streams previously returned by invocations of the getInputStream method.

Specified by:
close in interface AutoCloseable
Specified by:
close in interface Closeable
Throws:
IOException - if an I/O error has occurred

finalize

@Deprecated(since="9",
            forRemoval=true)
protected void finalize()
                 throws IOException
Deprecated, for removal: This API element is subject to removal in a future version.
The finalize method has been deprecated and will be removed. It is implemented as a no-op. Subclasses that override finalize in order to perform cleanup should be modified to use alternative cleanup mechanisms and to remove the overriding finalize method. The recommended cleanup for ZipFile object is to explicitly invoke close method when it is no longer in use, or use try-with-resources. If the close is not invoked explicitly the resources held by this object will be released when the instance becomes unreachable.

Ensures that the system resources held by this ZipFile object are released when there are no more references to it.

Overrides:
finalize in class Object
Throws:
IOException - if an I/O error has occurred
See Also:
WeakReference, PhantomReference