public abstract class ContentHandler extends Object
ContentHandler
is the superclass of all classes that read an Object
from a URLConnection
. An application does not generally call the getContent
method in this class directly. Instead, an application calls the getContent
method in class URL
or in URLConnection
. The application's content handler factory (an instance of a class that implements the interface ContentHandlerFactory
set up by a call to setContentHandlerFactory
) is called with a String
giving the MIME type of the object being received on the socket. The factory returns an instance of a subclass of ContentHandler
, and its getContent
method is called to create the object.
If no content handler could be found, URLConnection will look for a content handler in a user-definable set of places. Users can define a vertical-bar delimited set of class prefixes to search through by defining the java.content.handler.pkgs
system property. The class name must be of the form:
{package-prefix}.{major}.{minor}If no user-defined content handler is found, then the system tries to load a specific content-type handler from one of the built-in handlers, if one exists.where {major}.{minor} is formed by taking the content-type string, replacing all slash characters with a
period
('.'), and all other non-alphanumeric characters with the underscore character '_
'. The alphanumeric characters are specifically the 26 uppercase ASCII letters 'A
' through 'Z
', the 26 lowercase ASCII letters 'a
' through 'z
', and the 10 ASCII digits '0
' through '9
'.e.g. YoyoDyne.experimental.text.plain
If the loading of the content handler class would be performed by a classloader that is outside of the delegation chain of the caller, the JVM will need the RuntimePermission "getClassLoader".
Constructor | Description |
---|---|
ContentHandler() |
Constructor for subclasses to call. |
Modifier and Type | Method | Description |
---|---|---|
abstract Object |
getContent |
Given a URL connect stream positioned at the beginning of the representation of an object, this method reads that stream and creates an object from it. |
Object |
getContent |
Given a URL connect stream positioned at the beginning of the representation of an object, this method reads that stream and creates an object that matches one of the types specified. |
public ContentHandler()
public abstract Object getContent(URLConnection urlc) throws IOException
urlc
- a URL connection.ContentHandler
.IOException
- if an I/O error occurs while reading the object.public Object getContent(URLConnection urlc, Class[] classes) throws IOException
getContent(URLConnection)
and screen the return type for a match of the suggested types.urlc
- a URL connection.classes
- an array of types requestedContentHandler
that is the first match of the suggested types or null
if none of the requested are supported.IOException
- if an I/O error occurs while reading the object.
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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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https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/net/ContentHandler.html