JavaTM 2 Platform Std. Ed. v1.6.0
java.net
Class JarURLConnection
java.lang.Object
java.net.URLConnection
java.net.JarURLConnection
public abstract class JarURLConnection - extends URLConnection
A URL Connection to a Java ARchive (JAR) file or an entry in a JAR
file.
The syntax of a JAR URL is:
jar:<url>!/{entry}
for example:
jar:http://www.foo.com/bar/baz.jar!/COM/foo/Quux.class
Jar URLs should be used to refer to a JAR file or entries in
a JAR file. The example above is a JAR URL which refers to a JAR
entry. If the entry name is omitted, the URL refers to the whole
JAR file:
jar:http://www.foo.com/bar/baz.jar!/
Users should cast the generic URLConnection to a
JarURLConnection when they know that the URL they created is a JAR
URL, and they need JAR-specific functionality. For example:
URL url = new URL("jar:file:/home/duke/duke.jar!/");
JarURLConnection jarConnection = (JarURLConnection)url.openConnection();
Manifest manifest = jarConnection.getManifest();
JarURLConnection instances can only be used to read from JAR files.
It is not possible to get a OutputStream to modify or write
to the underlying JAR file using this class.
Examples:
- A Jar entry
jar:http://www.foo.com/bar/baz.jar!/COM/foo/Quux.class
- A Jar file
jar:http://www.foo.com/bar/baz.jar!/
- A Jar directory
jar:http://www.foo.com/bar/baz.jar!/COM/foo/
!/ is refered to as the separator.
When constructing a JAR url via new URL(context, spec) ,
the following rules apply:
- if there is no context URL and the specification passed to the
URL constructor doesn't contain a separator, the URL is considered
to refer to a JarFile.
- if there is a context URL, the context URL is assumed to refer
to a JAR file or a Jar directory.
- if the specification begins with a '/', the Jar directory is
ignored, and the spec is considered to be at the root of the Jar
file.
Examples:
- context: jar:http://www.foo.com/bar/jar.jar!/,
spec:baz/entry.txt
- url:jar:http://www.foo.com/bar/jar.jar!/baz/entry.txt
- context: jar:http://www.foo.com/bar/jar.jar!/baz,
spec:entry.txt
- url:jar:http://www.foo.com/bar/jar.jar!/baz/entry.txt
- context: jar:http://www.foo.com/bar/jar.jar!/baz,
spec:/entry.txt
- url:jar:http://www.foo.com/bar/jar.jar!/entry.txt
- Since:
- 1.2
- See Also:
URL ,
URLConnection ,
JarFile ,
JarInputStream ,
Manifest ,
ZipEntry
Constructor Summary |
protected |
JarURLConnection(URL url)
Creates the new JarURLConnection to the specified URL. |
Methods inherited from class java.net.URLConnection |
addRequestProperty, connect, getAllowUserInteraction, getConnectTimeout, getContent, getContent, getContentEncoding, getContentLength, getContentType, getDate, getDefaultAllowUserInteraction, getDefaultRequestProperty, getDefaultUseCaches, getDoInput, getDoOutput, getExpiration, getFileNameMap, getHeaderField, getHeaderField, getHeaderFieldDate, getHeaderFieldInt, getHeaderFieldKey, getHeaderFields, getIfModifiedSince, getInputStream, getLastModified, getOutputStream, getPermission, getReadTimeout, getRequestProperties, getRequestProperty, getURL, getUseCaches, guessContentTypeFromName, guessContentTypeFromStream, setAllowUserInteraction, setConnectTimeout, setContentHandlerFactory, setDefaultAllowUserInteraction, setDefaultRequestProperty, setDefaultUseCaches, setDoInput, setDoOutput, setFileNameMap, setIfModifiedSince, setReadTimeout, setRequestProperty, setUseCaches, toString |
jarFileURLConnection
protected URLConnection jarFileURLConnection
- The connection to the JAR file URL, if the connection has been
initiated. This should be set by connect.
JarURLConnection
protected JarURLConnection(URL url)
throws MalformedURLException
- Creates the new JarURLConnection to the specified URL.
- Parameters:
url - the URL
- Throws:
MalformedURLException - if no legal protocol
could be found in a specification string or the
string could not be parsed.
getJarFileURL
public URL getJarFileURL()
- Returns the URL for the Jar file for this connection.
- Returns:
- the URL for the Jar file for this connection.
getEntryName
public String getEntryName()
- Return the entry name for this connection. This method
returns null if the JAR file URL corresponding to this
connection points to a JAR file and not a JAR file entry.
- Returns:
- the entry name for this connection, if any.
getJarFile
public abstract JarFile getJarFile()
throws IOException
- Return the JAR file for this connection.
- Returns:
- the JAR file for this connection. If the connection is
a connection to an entry of a JAR file, the JAR file object is
returned
- Throws:
IOException - if an IOException occurs while trying to
connect to the JAR file for this connection.- See Also:
URLConnection.connect()
getManifest
public Manifest getManifest()
throws IOException
- Returns the Manifest for this connection, or null if none.
- Returns:
- the manifest object corresponding to the JAR file object
for this connection.
- Throws:
IOException - if getting the JAR file for this
connection causes an IOException to be trown.- See Also:
getJarFile()
getJarEntry
public JarEntry getJarEntry()
throws IOException
- Return the JAR entry object for this connection, if any. This
method returns null if the JAR file URL corresponding to this
connection points to a JAR file and not a JAR file entry.
- Returns:
- the JAR entry object for this connection, or null if
the JAR URL for this connection points to a JAR file.
- Throws:
IOException - if getting the JAR file for this
connection causes an IOException to be trown.- See Also:
getJarFile() ,
getJarEntry()
getAttributes
public Attributes getAttributes()
throws IOException
- Return the Attributes object for this connection if the URL
for it points to a JAR file entry, null otherwise.
- Returns:
- the Attributes object for this connection if the URL
for it points to a JAR file entry, null otherwise.
- Throws:
IOException - if getting the JAR entry causes an
IOException to be thrown.- See Also:
getJarEntry()
getMainAttributes
public Attributes getMainAttributes()
throws IOException
- Returns the main Attributes for the JAR file for this
connection.
- Returns:
- the main Attributes for the JAR file for this
connection.
- Throws:
IOException - if getting the manifest causes an
IOException to be thrown.- See Also:
getJarFile() ,
getManifest()
getCertificates
public Certificate[] getCertificates()
throws IOException
- Return the Certificate object for this connection if the URL
for it points to a JAR file entry, null otherwise. This method
can only be called once
the connection has been completely verified by reading
from the input stream until the end of the stream has been
reached. Otherwise, this method will return
null
- Returns:
- the Certificate object for this connection if the URL
for it points to a JAR file entry, null otherwise.
- Throws:
IOException - if getting the JAR entry causes an
IOException to be thrown.- See Also:
getJarEntry()
Copyright 2003 Sun Microsystems, Inc. All rights reserved
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