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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package javax.imageio.spi;
import java.util.Locale;
import javax.imageio.spi.RegisterableService;
import javax.imageio.spi.ServiceRegistry;
/**
* A superinterface for functionality common to all Image I/O service
* provider interfaces (SPIs). For more information on service
* provider classes, see the class comment for the
* <code>IIORegistry</code> class.
*
* @see IIORegistry
* @see javax.imageio.spi.ImageReaderSpi
* @see javax.imageio.spi.ImageWriterSpi
* @see javax.imageio.spi.ImageTranscoderSpi
* @see javax.imageio.spi.ImageInputStreamSpi
*
*/
public abstract class IIOServiceProvider implements RegisterableService {
/**
* A <code>String</code> to be returned from
* <code>getVendorName</code>, initially <code>null</code>.
* Constructors should set this to a non-<code>null</code> value.
*/
protected String vendorName;
/**
* A <code>String</code> to be returned from
* <code>getVersion</code>, initially null. Constructors should
* set this to a non-<code>null</code> value.
*/
protected String version;
/**
* Constructs an <code>IIOServiceProvider</code> with a given
* vendor name and version identifier.
*
* @param vendorName the vendor name.
* @param version a version identifier.
*
* @exception IllegalArgumentException if <code>vendorName</code>
* is <code>null</code>.
* @exception IllegalArgumentException if <code>version</code>
* is <code>null</code>.
*/
public IIOServiceProvider(String vendorName,
String version) {
if (vendorName == null) {
throw new IllegalArgumentException("vendorName == null!");
}
if (version == null) {
throw new IllegalArgumentException("version == null!");
}
this.vendorName = vendorName;
this.version = version;
}
/**
* Constructs a blank <code>IIOServiceProvider</code>. It is up
* to the subclass to initialize instance variables and/or
* override method implementations in order to ensure that the
* <code>getVendorName</code> and <code>getVersion</code> methods
* will return non-<code>null</code> values.
*/
public IIOServiceProvider() {
}
/**
* A callback that will be called exactly once after the Spi class
* has been instantiated and registered in a
* <code>ServiceRegistry</code>. This may be used to verify that
* the environment is suitable for this service, for example that
* native libraries can be loaded. If the service cannot function
* in the environment where it finds itself, it should deregister
* itself from the registry.
*
* <p> Only the registry should call this method.
*
* <p> The default implementation does nothing.
*
* @see ServiceRegistry#registerServiceProvider(Object provider)
*/
public void onRegistration(ServiceRegistry registry,
Class<?> category) {}
/**
* A callback that will be whenever the Spi class has been
* deregistered from a <code>ServiceRegistry</code>.
*
* <p> Only the registry should call this method.
*
* <p> The default implementation does nothing.
*
* @see ServiceRegistry#deregisterServiceProvider(Object provider)
*/
public void onDeregistration(ServiceRegistry registry,
Class<?> category) {}
/**
* Returns the name of the vendor responsible for creating this
* service provider and its associated implementation. Because
* the vendor name may be used to select a service provider,
* it is not localized.
*
* <p> The default implementation returns the value of the
* <code>vendorName</code> instance variable.
*
* @return a non-<code>null</code> <code>String</code> containing
* the name of the vendor.
*/
public String getVendorName() {
return vendorName;
}
/**
* Returns a string describing the version
* number of this service provider and its associated
* implementation. Because the version may be used by transcoders
* to identify the service providers they understand, this method
* is not localized.
*
* <p> The default implementation returns the value of the
* <code>version</code> instance variable.
*
* @return a non-<code>null</code> <code>String</code> containing
* the version of this service provider.
*/
public String getVersion() {
return version;
}
/**
* Returns a brief, human-readable description of this service
* provider and its associated implementation. The resulting
* string should be localized for the supplied
* <code>Locale</code>, if possible.
*
* @param locale a <code>Locale</code> for which the return value
* should be localized.
*
* @return a <code>String</code> containing a description of this
* service provider.
*/
public abstract String getDescription(Locale locale);
}