URLStreamHandler (Java Platform SE 8 ) (original) (raw)

java.lang.Object
- java.net.URLStreamHandler

public abstract class URLStreamHandler
extends Object
The abstract class URLStreamHandler is the common superclass for all stream protocol handlers. A stream protocol handler knows how to make a connection for a particular protocol type, such as http or https.
In most cases, an instance of a URLStreamHandler subclass is not created directly by an application. Rather, the first time a protocol name is encountered when constructing aURL, the appropriate stream protocol handler is automatically loaded.
Since:
JDK1.0
See Also:
URL.URL(java.lang.String, java.lang.String, int, java.lang.String)

Constructor Summary

Constructors

Constructor	Description
URLStreamHandler()

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods Deprecated Methods

Modifier and Type	Method	Description
protected boolean	equals(URL u1,URL u2)	Provides the default equals calculation.
protected int	getDefaultPort()	Returns the default port for a URL parsed by this handler.
protected InetAddress	getHostAddress(URL u)	Get the IP address of our host.
protected int	hashCode(URL u)	Provides the default hash calculation.
protected boolean	hostsEqual(URL u1,URL u2)	Compares the host components of two URLs.
protected abstract URLConnection	openConnection(URL u)	Opens a connection to the object referenced by theURL argument.
protected URLConnection	openConnection(URL u,Proxy p)	Same as openConnection(URL), except that the connection will be made through the specified proxy; Protocol handlers that do not support proxying will ignore the proxy parameter and make a normal connection.
protected void	parseURL(URL u,String spec, int start, int limit)	Parses the string representation of a URL into aURL object.
protected boolean	sameFile(URL u1,URL u2)	Compare two urls to see whether they refer to the same file, i.e., having the same protocol, host, port, and path.
protected void	setURL(URL u,String protocol,String host, int port,String file,String ref)	Deprecated.
protected void	setURL(URL u,String protocol,String host, int port,String authority,String userInfo,String path,String query,String ref)	Sets the fields of the URL argument to the indicated values.
protected String	toExternalForm(URL u)	Converts a URL of a specific protocol to aString.

   * ### Methods inherited from class java.lang.[Object](../../java/lang/Object.html "class in java.lang")  
   `[clone](../../java/lang/Object.html#clone--), [equals](../../java/lang/Object.html#equals-java.lang.Object-), [finalize](../../java/lang/Object.html#finalize--), [getClass](../../java/lang/Object.html#getClass--), [hashCode](../../java/lang/Object.html#hashCode--), [notify](../../java/lang/Object.html#notify--), [notifyAll](../../java/lang/Object.html#notifyAll--), [toString](../../java/lang/Object.html#toString--), [wait](../../java/lang/Object.html#wait--), [wait](../../java/lang/Object.html#wait-long-), [wait](../../java/lang/Object.html#wait-long-int-)`

Constructor Detail

 * #### URLStreamHandler  
 public URLStreamHandler()

Method Detail

* #### openConnection  
protected abstract [URLConnection](../../java/net/URLConnection.html "class in java.net") openConnection([URL](../../java/net/URL.html "class in java.net") u)  
                                         throws [IOException](../../java/io/IOException.html "class in java.io")  
Opens a connection to the object referenced by the`URL` argument. This method should be overridden by a subclass.  
If for the handler's protocol (such as HTTP or JAR), there exists a public, specialized URLConnection subclass belonging to one of the following packages or one of their subpackages: java.lang, java.io, java.util, java.net, the connection returned will be of that subclass. For example, for HTTP an HttpURLConnection will be returned, and for JAR a JarURLConnection will be returned.  
Parameters:  
`u` \- the URL that this connects to.  
Returns:  
a `URLConnection` object for the `URL`.  
Throws:  
`[IOException](../../java/io/IOException.html "class in java.io")` \- if an I/O error occurs while opening the connection.  
* #### openConnection  
protected [URLConnection](../../java/net/URLConnection.html "class in java.net") openConnection([URL](../../java/net/URL.html "class in java.net") u,  
                                       [Proxy](../../java/net/Proxy.html "class in java.net") p)  
                                throws [IOException](../../java/io/IOException.html "class in java.io")  
Same as openConnection(URL), except that the connection will be made through the specified proxy; Protocol handlers that do not support proxying will ignore the proxy parameter and make a normal connection. Calling this method preempts the system's default ProxySelector settings.  
Parameters:  
`u` \- the URL that this connects to.  
`p` \- the proxy through which the connection will be made. If direct connection is desired, Proxy.NO\_PROXY should be specified.  
Returns:  
a `URLConnection` object for the `URL`.  
Throws:  
`[IOException](../../java/io/IOException.html "class in java.io")` \- if an I/O error occurs while opening the connection.  
`[IllegalArgumentException](../../java/lang/IllegalArgumentException.html "class in java.lang")` \- if either u or p is null, or p has the wrong type.  
`[UnsupportedOperationException](../../java/lang/UnsupportedOperationException.html "class in java.lang")` \- if the subclass that implements the protocol doesn't support this method.  
Since:  
1.5  
* #### parseURL  
protected void parseURL([URL](../../java/net/URL.html "class in java.net") u,  
                        [String](../../java/lang/String.html "class in java.lang") spec,  
                        int start,  
                        int limit)  
Parses the string representation of a `URL` into a`URL` object.  
 If there is any inherited context, then it has already been copied into the `URL` argument.  
 The `parseURL` method of `URLStreamHandler` parses the string representation as if it were an`http` specification. Most URL protocol families have a similar parsing. A stream protocol handler for a protocol that has a different syntax must override this routine.  
Parameters:  
`u` \- the `URL` to receive the result of parsing the spec.  
`spec` \- the `String` representing the URL that must be parsed.  
`start` \- the character index at which to begin parsing. This is just past the '`:`' (if there is one) that specifies the determination of the protocol name.  
`limit` \- the character position to stop parsing at. This is the end of the string or the position of the "`#`" character, if present. All information after the sharp sign indicates an anchor.  
* #### getDefaultPort  
protected int getDefaultPort()  
Returns the default port for a URL parsed by this handler. This method is meant to be overidden by handlers with default port numbers.  
Returns:  
the default port for a `URL` parsed by this handler.  
Since:  
1.3  
* #### equals  
protected boolean equals([URL](../../java/net/URL.html "class in java.net") u1,  
                         [URL](../../java/net/URL.html "class in java.net") u2)  
Provides the default equals calculation. May be overidden by handlers for other protocols that have different requirements for equals(). This method requires that none of its arguments is null. This is guaranteed by the fact that it is only called by java.net.URL class.  
Parameters:  
`u1` \- a URL object  
`u2` \- a URL object  
Returns:  
`true` if the two urls are considered equal, ie. they refer to the same fragment in the same file.  
Since:  
1.3  
* #### hashCode  
protected int hashCode([URL](../../java/net/URL.html "class in java.net") u)  
Provides the default hash calculation. May be overidden by handlers for other protocols that have different requirements for hashCode calculation.  
Parameters:  
`u` \- a URL object  
Returns:  
an `int` suitable for hash table indexing  
Since:  
1.3  
* #### sameFile  
protected boolean sameFile([URL](../../java/net/URL.html "class in java.net") u1,  
                           [URL](../../java/net/URL.html "class in java.net") u2)  
Compare two urls to see whether they refer to the same file, i.e., having the same protocol, host, port, and path. This method requires that none of its arguments is null. This is guaranteed by the fact that it is only called indirectly by java.net.URL class.  
Parameters:  
`u1` \- a URL object  
`u2` \- a URL object  
Returns:  
true if u1 and u2 refer to the same file  
Since:  
1.3  
* #### getHostAddress  
protected [InetAddress](../../java/net/InetAddress.html "class in java.net") getHostAddress([URL](../../java/net/URL.html "class in java.net") u)  
Get the IP address of our host. An empty host field or a DNS failure will result in a null return.  
Parameters:  
`u` \- a URL object  
Returns:  
an `InetAddress` representing the host IP address.  
Since:  
1.3  
* #### hostsEqual  
protected boolean hostsEqual([URL](../../java/net/URL.html "class in java.net") u1,  
                             [URL](../../java/net/URL.html "class in java.net") u2)  
Compares the host components of two URLs.  
Parameters:  
`u1` \- the URL of the first host to compare  
`u2` \- the URL of the second host to compare  
Returns:  
`true` if and only if they are equal, `false` otherwise.  
Since:  
1.3  
* #### toExternalForm  
protected [String](../../java/lang/String.html "class in java.lang") toExternalForm([URL](../../java/net/URL.html "class in java.net") u)  
Converts a `URL` of a specific protocol to a`String`.  
Parameters:  
`u` \- the URL.  
Returns:  
a string representation of the `URL` argument.  
* #### setURL  
protected void setURL([URL](../../java/net/URL.html "class in java.net") u,  
                      [String](../../java/lang/String.html "class in java.lang") protocol,  
                      [String](../../java/lang/String.html "class in java.lang") host,  
                      int port,  
                      [String](../../java/lang/String.html "class in java.lang") authority,  
                      [String](../../java/lang/String.html "class in java.lang") userInfo,  
                      [String](../../java/lang/String.html "class in java.lang") path,  
                      [String](../../java/lang/String.html "class in java.lang") query,  
                      [String](../../java/lang/String.html "class in java.lang") ref)  
Sets the fields of the `URL` argument to the indicated values. Only classes derived from URLStreamHandler are able to use this method to set the values of the URL fields.  
Parameters:  
`u` \- the URL to modify.  
`protocol` \- the protocol name.  
`host` \- the remote host value for the URL.  
`port` \- the port on the remote machine.  
`authority` \- the authority part for the URL.  
`userInfo` \- the userInfo part of the URL.  
`path` \- the path component of the URL.  
`query` \- the query part for the URL.  
`ref` \- the reference.  
Throws:  
`[SecurityException](../../java/lang/SecurityException.html "class in java.lang")` \- if the protocol handler of the URL is different from this one  
Since:  
1.3  
See Also:  
[URL.set(java.lang.String, java.lang.String, int, java.lang.String, java.lang.String)](../../java/net/URL.html#set-java.lang.String-java.lang.String-int-java.lang.String-java.lang.String-)  
* #### setURL  
[@Deprecated](../../java/lang/Deprecated.html "annotation in java.lang")  
protected void setURL([URL](../../java/net/URL.html "class in java.net") u,  
                                  [String](../../java/lang/String.html "class in java.lang") protocol,  
                                  [String](../../java/lang/String.html "class in java.lang") host,  
                                  int port,  
                                  [String](../../java/lang/String.html "class in java.lang") file,  
                                  [String](../../java/lang/String.html "class in java.lang") ref)  
Deprecated.  
Sets the fields of the `URL` argument to the indicated values. Only classes derived from URLStreamHandler are able to use this method to set the values of the URL fields.  
Parameters:  
`u` \- the URL to modify.  
`protocol` \- the protocol name. This value is ignored since 1.2.  
`host` \- the remote host value for the URL.  
`port` \- the port on the remote machine.  
`file` \- the file.  
`ref` \- the reference.  
Throws:  
`[SecurityException](../../java/lang/SecurityException.html "class in java.lang")` \- if the protocol handler of the URL is different from this one

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URLStreamHandler (Java Platform SE 8 ) (original) (raw)

Constructor Summary

Method Summary

Constructor Detail

Method Detail