001/* IIOServiceProvider.java -- General service provider for image I/O.
002   Copyright (C) 2004, 2005  Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038
039package javax.imageio.spi;
040
041import java.util.Locale;
042
043
044/**
045 * An abstract superclass for service providers that perform image I/O.
046 *
047 * @since 1.4
048 *
049 * @author Sascha Brawer (brawer@dandelis.ch)
050 */
051public abstract class IIOServiceProvider
052  implements RegisterableService
053{
054  /**
055   * The vendor of this service provider, or <code>null</code> if the
056   * subclass constructor did not set this field.
057   *
058   * @see #getVendorName()
059   */
060  protected String vendorName;
061
062
063  /**
064   * The version of this service provider, or <code>null</code> if the
065   * subclass constructor did not set this field.
066   *
067   * @see #getVersion()
068   */
069  protected String version;
070
071
072  /**
073   * Constructs a general <code>IIOServiceProvider</code>, given the
074   * vendor name and a version string.
075   *
076   * @throws IllegalArgumentException if <code>vendorName</code>
077   * or <code>version</code> is <code>null</code>.
078   */
079  public IIOServiceProvider(String vendorName, String version)
080  {
081    if (vendorName == null || version == null)
082      throw new IllegalArgumentException();
083
084    this.vendorName = vendorName;
085    this.version = version;
086  }
087
088
089  /**
090   * Constructs a general <code>IIOServiceProvider</code> without
091   * specifying a vendor name and a version string. The subclass
092   * constructor should set the {@link #vendorName} and {@link
093   * #version} to non-null values.
094   */
095  public IIOServiceProvider()
096  {
097  }
098
099
100  /**
101   * Informs this service provider that it has been registered in a
102   * {@link ServiceRegistry}. If this provider gets registered as an
103   * implementor for several service categories, its
104   * <code>onRegistration</code> method will be called multiple times.
105   * The default implementation does nothing.
106   *
107   * @param registry the registry to which this service provider has
108   * been added.
109   *
110   * @param category the service category for which this provider has
111   * been registered as an implementor.
112   */
113  public void onRegistration(ServiceRegistry registry, Class<?> category)
114  {
115  }
116
117
118  /**
119   * Informs this service provider that it has been de-registered from
120   * a {@link ServiceRegistry}. If this provider had been registered
121   * as an implementor for several service categories, its
122   * <code>onDeregistration</code> method will be called multiple
123   * times. The default implementation does nothing.
124   *
125   * @param registry the registry from which this service provider has
126   * been removed.
127   *
128   * @param category the service category for which this provider has
129   * been registered as an implementor.
130   */
131  public void onDeregistration(ServiceRegistry registry, Class<?> category)
132  {
133  }
134
135
136  /**
137   * Returns the name of the vendor of this service provider.
138   */
139  public String getVendorName()
140  {
141    return vendorName;
142  }
143
144
145  /**
146   * Returns an identifier string for the version of this service
147   * provider.
148   */
149  public String getVersion()
150  {
151    return version;
152  }
153
154
155  /**
156   * Returns a short description of this service provider that can be
157   * presented to a human user.
158   *
159   * @param locale the locale for which the description string should
160   * be localized.
161   */
162  public abstract String getDescription(Locale locale);
163}