JarFile JDK 1.6)

Description

public class JarFile

The JarFile class is used to read the contents of a jar file from any file that can be opened with java.io.RandomAccessFile.

The JarFile class is used to read the contents of a jar file from any file that can be opened with java.io.RandomAccessFile. It extends the class java.util.zip.ZipFile with support for reading an optional Manifest entry. The Manifest can be used to specify meta-information about the jar file and its entries.

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

See also: Manifest ZipFile JarEntry

Constructors

public JarFile (File file) throws IOException

Creates a new JarFile to read from the specified File object.

Creates a new JarFile to read from the specified
File object. The JarFile will be verified if
it is signed.
Parameters:
- file - the jar file to be opened for reading
Throws:
- IOException - if an I/O error has occurred
- SecurityException - if access to the file is denied by the SecurityManager

public JarFile (File file, boolean verify) throws IOException

Creates a new JarFile to read from the specified File object.

Creates a new JarFile to read from the specified
File object.
Parameters:
- file - the jar file to be opened for reading
- verify - whether or not to verify the jar file if it is signed.
Throws:
- IOException - if an I/O error has occurred
- SecurityException - if access to the file is denied by the SecurityManager.

public JarFile (File file, boolean verify, int mode) throws IOException

Creates a new JarFile to read from the specified File object in the specified mode.

Creates a new JarFile to read from the specified
File object in the specified mode. The mode argument
must be either OPEN_READ or OPEN_READ | OPEN_DELETE.
Parameters:
- file - the jar file to be opened for reading
- verify - whether or not to verify the jar file if it is signed.
- mode - the mode in which the file is to be opened
Throws:
- IOException - if an I/O error has occurred
- IllegalArgumentException - if the mode argument is invalid
- SecurityException - if access to the file is denied by the SecurityManager
Since: 1.3

public JarFile (String name) throws IOException

Creates a new JarFile to read from the specified file name.

Creates a new JarFile to read from the specified
file name. The JarFile will be verified if
it is signed.
Parameters:
- name - the name of the jar file to be opened for reading
Throws:
- IOException - if an I/O error has occurred
- SecurityException - if access to the file is denied by the SecurityManager

public JarFile (String name, boolean verify) throws IOException

Creates a new JarFile to read from the specified file name.

Creates a new JarFile to read from the specified
file name.
Parameters:
- name - the name of the jar file to be opened for reading
- verify - whether or not to verify the jar file if it is signed.
Throws:
- IOException - if an I/O error has occurred
- SecurityException - if access to the file is denied by the SecurityManager

Methods

Hide/Show inherited methods

public void close () throws IOException [Inherited From ZipFile]

Closes the ZIP file.

public Enumeration<JarEntry> entries () [Overrides ZipFile]

Returns an enumeration of the zip file entries.

protected void finalize () throws IOException [Inherited From ZipFile]

Ensures that the close method of this ZIP file is called when there are no more references to it.

Since the time when GC would invoke this method is undetermined, it is strongly recommended that applications invoke the close method as soon they have finished accessing this ZipFile. This will prevent holding up system resources for an undetermined length of time.
Throws:
- IOException - if an I/O error has occurred
See Also: ZipFile.close(),

public ZipEntry getEntry (String name) [Overrides ZipFile]

Returns the ZipEntry for the given entry name or null if not found.

Returns the ZipEntry for the given entry name or
null if not found.
Returns: the ZipEntry for the given entry name or null if not found
Parameters:
- name - the jar file entry name
Throws:
- IllegalStateException - may be thrown if the jar file has been closed
See Also: ZipEntry,

publicsynchronized InputStream getInputStream (ZipEntry ze) throws IOException [Overrides ZipFile]

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

public JarEntry getJarEntry (String name)

Returns the JarEntry for the given entry name or null if not found.

Returns the JarEntry for the given entry name or
null if not found.
Returns: the JarEntry for the given entry name or null if not found.
Parameters:
- name - the jar file entry name
Throws:
- IllegalStateException - may be thrown if the jar file has been closed
See Also: JarEntry,

public Manifest getManifest () throws IOException

Returns the jar file manifest, or null if none.

Returns the jar file manifest, or null if none.
Returns: the jar file manifest, or null if none
Throws:
- IllegalStateException - may be thrown if the jar file has been closed

public String getName () [Inherited From ZipFile]

Returns the path name of the ZIP file.

pack-private boolean hasClassPathAttribute () throws IOException

public int size () [Inherited From ZipFile]

Returns the number of entries in the ZIP file.