JarFile
Class JarFile
- java.lang.Object
-
- java.util.zip.ZipFile
-
- java.util.jar.JarFile
- All Implemented Interfaces:
- Closeable, AutoCloseable
public class JarFile extends ZipFile
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. If the verify flag is on when opening a signed jar file, the content of the file is verified against its signature embedded inside the file. Please note that the verification process does not include validating the signer's certificate. A caller should inspect the return value of JarEntry.getCodeSigners()
to further determine if the signature can be trusted.
Fields
MANIFEST_NAME
public static final String MANIFEST_NAME
The JAR manifest file name.
LOCSIG
public static final long LOCSIG
EXTSIG
public static final long EXTSIG
CENSIG
public static final long CENSIG
ENDSIG
public static final long ENDSIG
LOCHDR
public static final int LOCHDR
EXTHDR
public static final int EXTHDR
CENHDR
public static final int CENHDR
ENDHDR
public static final int ENDHDR
LOCVER
public static final int LOCVER
LOCFLG
public static final int LOCFLG
LOCHOW
public static final int LOCHOW
LOCTIM
public static final int LOCTIM
LOCCRC
public static final int LOCCRC
LOCSIZ
public static final int LOCSIZ
LOCLEN
public static final int LOCLEN
LOCNAM
public static final int LOCNAM
LOCEXT
public static final int LOCEXT
EXTCRC
public static final int EXTCRC
EXTSIZ
public static final int EXTSIZ
EXTLEN
public static final int EXTLEN
CENVEM
public static final int CENVEM
CENVER
public static final int CENVER
CENFLG
public static final int CENFLG
CENHOW
public static final int CENHOW
CENTIM
public static final int CENTIM
CENCRC
public static final int CENCRC
CENSIZ
public static final int CENSIZ
CENLEN
public static final int CENLEN
CENNAM
public static final int CENNAM
CENEXT
public static final int CENEXT
CENCOM
public static final int CENCOM
CENDSK
public static final int CENDSK
CENATT
public static final int CENATT
CENATX
public static final int CENATX
CENOFF
public static final int CENOFF
ENDSUB
public static final int ENDSUB
ENDTOT
public static final int ENDTOT
ENDSIZ
public static final int ENDSIZ
ENDOFF
public static final int ENDOFF
ENDCOM
public static final int ENDCOM
Constructors
JarFile
public JarFile(String name) throws IOException
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
JarFile
public JarFile(String name, boolean verify) throws IOException
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
JarFile
public JarFile(File file) throws IOException
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
JarFile
public JarFile(File file, boolean verify) throws IOException
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.
JarFile
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. 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 themode
argument is invalid -
SecurityException
- if access to the file is denied by the SecurityManager - Since:
- 1.3
Methods
getManifest
public Manifest getManifest() throws IOException
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 -
IOException
- if an I/O error has occurred
getJarEntry
public JarEntry getJarEntry(String name)
Returns the JarEntry
for the given entry name or null
if not found.
- Parameters:
-
name
- the jar file entry name - Returns:
- the
JarEntry
for the given entry name ornull
if not found. - Throws:
-
IllegalStateException
- may be thrown if the jar file has been closed - See Also:
JarEntry
getEntry
public ZipEntry getEntry(String name)
Returns the ZipEntry
for the given entry name or null
if not found.
- Overrides:
-
getEntry
in classZipFile
- Parameters:
-
name
- the jar file entry name - Returns:
- the
ZipEntry
for the given entry name ornull
if not found - Throws:
-
IllegalStateException
- may be thrown if the jar file has been closed - See Also:
ZipEntry
entries
public Enumeration<JarEntry> entries()
Returns an enumeration of the zip file entries.
stream
public Stream<JarEntry> stream()
Description copied from class: ZipFile
Return 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.
getInputStream
public InputStream getInputStream(ZipEntry ze) throws IOException
Returns an input stream for reading the contents of the specified zip file entry.
- Overrides:
-
getInputStream
in classZipFile
- Parameters:
-
ze
- the zip file entry - Returns:
- an input stream for reading the contents of the specified zip file entry
- Throws:
-
ZipException
- if a zip file format error has occurred -
IOException
- if an I/O error has occurred -
SecurityException
- if any of the jar file entries are incorrectly signed. -
IllegalStateException
- may be thrown if the jar file has been closed
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Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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