Package net.sf.saxon.resource

Class ResourceLoader

java.lang.Object

net.sf.saxon.resource.ResourceLoader

public class ResourceLoader
extends Object

The class provides a static method for loading resources from a URL. This method follows HTTP 301 and 302 redirects.

Field Summary

Fields

Modifier and Type	Field	Description
static int	MAX_REDIRECTS	The maximum number of redirects to follow before throwing an IOException.

Constructor Summary

Constructors

Constructor	Description
ResourceLoader()

Method Summary

Modifier and Type	Method	Description
static BufferedReader	getReaderFromStream(InputStream inputStream, String resourceEncoding)	Get a reader corresponding to a binary input stream and an encoding.
static StreamSource	typedStreamSource(Configuration config, String url)
static URLConnection	urlConnection(URL url)	Open a URLConnection to the resource identified by the URI.
static Reader	urlReader(Configuration config, String url, String requestedEncoding)	Open a reader to retrieve the content identified by the URI.
static InputStream	urlStream(Configuration config, String url)	Open a stream to retrieve the content identified by the URI.

Methods inherited from class java.lang.Object

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

Field Details

MAX_REDIRECTS

public static int MAX_REDIRECTS

The maximum number of redirects to follow before throwing an IOException. If you allow the underlying Java URL class to follow redirects, it gives up after 20 hops.

Constructor Details

ResourceLoader

public ResourceLoader()

Method Details

urlConnection

public static URLConnection urlConnection(URL url)
                                   throws IOException

Open a URLConnection to the resource identified by the URI. For HTTP URIs, this method will follow up to MAX_REDIRECTS redirects or until it detects a loop; the connection returned in this case is to the first resource that did not return a 301 or 302 response code.

Parameters:

url - The URL to retrieve.

Returns:

An InputStream for the resource content.

Throws:

IOException - If more than MAX_REDIRECTS are occur or if a loop is detected.

urlStream

public static InputStream urlStream(Configuration config,
 String url)
                             throws IOException

Open a stream to retrieve the content identified by the URI. If the URI is a classpath: URI, then it will be retrieved with the configuration's dynamic loader. For HTTP URIs, this method will follow up to MAX_REDIRECTS redirects or until it detects a loop. This method automatically accepts and decompresses gzip encoded responses.

Parameters:

config - The current configuration.

url - The URL to retrieve.

Returns:

An InputStream for the resource content.

Throws:

IOException - If more than MAX_REDIRECTS are occur or if a loop is detected.

typedStreamSource

public static StreamSource typedStreamSource(Configuration config,
 String url)
                                      throws IOException

Throws:

IOException

urlReader

public static Reader urlReader(Configuration config,
 String url,
 String requestedEncoding)
                        throws IOException

Open a reader to retrieve the content identified by the URI. This handles HTTP redirects in the same way as urlStream(net.sf.saxon.Configuration, java.lang.String), but then it also wraps the stream in a Reader, using the logic prescribed for the fn:unparsed-text function.

Parameters:

url - The URL to retrieve.

requestedEncoding - The requested encoding. This is used only as a fallback, following the rules of the fn:unparsed-text specification

Returns:

A Reader for the resource content.

Throws:

IOException - If more than MAX_REDIRECTS are occur or if a loop is detected.

getReaderFromStream

public static BufferedReader getReaderFromStream(InputStream inputStream,
 String resourceEncoding)
                                          throws UnsupportedEncodingException

Get a reader corresponding to a binary input stream and an encoding. The mapping is such that any encoding errors that are detected lead to a fatal error, rather than being repaired or ignored

Parameters:

inputStream - the input stream. Non-null.

resourceEncoding - the encoding. Non-null

Returns:

a corresponding reader.

Throws:

UnsupportedEncodingException - if there's a problem with the encoding