java.util.jar
Class JarFile

java.lang.Object
  java.util.zip.ZipFile
      java.util.jar.JarFile

All Implemented Interfaces:

ZipConstants

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.

Since:

1.2

Author:

David Connelly

See Also:

Manifest, ZipFile, JarEntry

Nested Class Summary

private class

JarFile.JarFileEntry

Nested classes inherited from class java.util.zip.ZipFile

Field Summary

private boolean	computedHasClassPathAttribute
private boolean	hasClassPathAttribute
private static String	javaHome
private JarVerifier	jv
private boolean	jvInitialized
private static int[]	lastOcc
private Manifest	man
private JarEntry	manEntry
static String	MANIFEST_NAME The JAR manifest file name.
private boolean	manLoaded
private static int[]	optoSft
private static char[]	src
private boolean	verify

Fields inherited from class java.util.zip.ZipFile

CENATT, CENATX, CENCOM, CENCRC, CENDSK, CENEXT, CENFLG, CENHDR, CENHOW, CENLEN, CENNAM, CENOFF, CENSIG, CENSIZ, CENTIM, CENVEM, CENVER, ENDCOM, ENDHDR, ENDOFF, ENDSIG, ENDSIZ, ENDSUB, ENDTOT, EXTCRC, EXTHDR, EXTLEN, EXTSIG, EXTSIZ, LOCCRC, LOCEXT, LOCFLG, LOCHDR, LOCHOW, LOCLEN, LOCNAM, LOCSIG, LOCSIZ, LOCTIM, LOCVER, OPEN_DELETE, OPEN_READ

Constructor Summary

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

JarFile(File file, boolean verify)
Creates a new JarFile to read from the specified File object.

JarFile(File file, boolean verify, int mode)
Creates a new JarFile to read from the specified File object in the specified mode.

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

JarFile(String name, boolean verify)
Creates a new JarFile to read from the specified file name.

Method Summary

Enumeration	entries() Returns an enumeration of the ZIP file entries.
private byte[]	getBytes(ZipEntry ze)
ZipEntry	getEntry(String name) Returns the ZipEntry for the given entry name or null if not found.
InputStream	getInputStream(ZipEntry ze) Returns an input stream for reading the contents of the specified ZIP file entry.
JarEntry	getJarEntry(String name) Returns the JarEntry for the given entry name or null if not found.
Manifest	getManifest() Returns the JAR file manifest, or null if none.
private String[]	getMetaInfEntryNames()
(package private) boolean	hasClassPathAttribute()
private void	initializeVerifier()
private boolean	isKnownToNotHaveClassPathAttribute()
private void	maybeInstantiateVerifier()

Methods inherited from class java.util.zip.ZipFile

close, finalize, getName, size

Methods inherited from class java.lang.Object

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

Field Detail

man

private Manifest man

manEntry

private JarEntry manEntry

manLoaded

private boolean manLoaded

jv

private JarVerifier jv

jvInitialized

private boolean jvInitialized

verify

private boolean verify

computedHasClassPathAttribute

private boolean computedHasClassPathAttribute

hasClassPathAttribute

private boolean hasClassPathAttribute

MANIFEST_NAME

public static final String MANIFEST_NAME

The JAR manifest file name.

See Also:

Constant Field Values

lastOcc

private static int[] lastOcc

optoSft

private static int[] optoSft

src

private static char[] src

javaHome

private static String javaHome

Constructor Detail

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 JarFile 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 JarFile 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 JarFile 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

Method Detail

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:

IOException

getMetaInfEntryNames

private String[] getMetaInfEntryNames()

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 or null if not found.

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 class ZipFile

Parameters:

name - the JAR file entry name

Returns:

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

See Also:

ZipEntry

entries

public Enumeration entries()

Returns an enumeration of the ZIP file entries.

Overrides:

entries in class ZipFile

Returns:

an enumeration of the ZIP file entries

maybeInstantiateVerifier

private void maybeInstantiateVerifier()
                               throws IOException

Throws:

IOException

initializeVerifier

private void initializeVerifier()

getBytes

private byte[] getBytes(ZipEntry ze)
                 throws IOException

Throws:

IOException

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 class ZipFile

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 format error has occurred

IOException - if an I/O error has occurred

SecurityException - if any of the JarFile entries are incorrectly signed.

hasClassPathAttribute

boolean hasClassPathAttribute()
                        throws IOException

Throws:

IOException

isKnownToNotHaveClassPathAttribute

private boolean isKnownToNotHaveClassPathAttribute()