jaroslav@110: /**
jaroslav@358:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
jaroslav@110:  *
jaroslav@551:  * Copyright 2013-2014 Oracle and/or its affiliates. All rights reserved.
jaroslav@110:  *
jaroslav@358:  * Oracle and Java are registered trademarks of Oracle and/or its affiliates.
jaroslav@358:  * Other names may be trademarks of their respective owners.
jaroslav@110:  *
jaroslav@358:  * The contents of this file are subject to the terms of either the GNU
jaroslav@358:  * General Public License Version 2 only ("GPL") or the Common
jaroslav@358:  * Development and Distribution License("CDDL") (collectively, the
jaroslav@358:  * "License"). You may not use this file except in compliance with the
jaroslav@358:  * License. You can obtain a copy of the License at
jaroslav@358:  * http://www.netbeans.org/cddl-gplv2.html
jaroslav@358:  * or nbbuild/licenses/CDDL-GPL-2-CP. See the License for the
jaroslav@358:  * specific language governing permissions and limitations under the
jaroslav@358:  * License.  When distributing the software, include this License Header
jaroslav@358:  * Notice in each file and include the License file at
jaroslav@358:  * nbbuild/licenses/CDDL-GPL-2-CP.  Oracle designates this
jaroslav@358:  * particular file as subject to the "Classpath" exception as provided
jaroslav@358:  * by Oracle in the GPL Version 2 section of the License file that
jaroslav@358:  * accompanied this code. If applicable, add the following below the
jaroslav@358:  * License Header, with the fields enclosed by brackets [] replaced by
jaroslav@358:  * your own identifying information:
jaroslav@358:  * "Portions Copyrighted [year] [name of copyright owner]"
jaroslav@358:  *
jaroslav@358:  * Contributor(s):
jaroslav@358:  *
jaroslav@358:  * The Original Software is NetBeans. The Initial Developer of the Original
jaroslav@551:  * Software is Oracle. Portions Copyright 2013-2014 Oracle. All Rights Reserved.
jaroslav@358:  *
jaroslav@358:  * If you wish your version of this file to be governed by only the CDDL
jaroslav@358:  * or only the GPL Version 2, indicate your decision by adding
jaroslav@358:  * "[Contributor] elects to include this software in this distribution
jaroslav@358:  * under the [CDDL or GPL Version 2] license." If you do not indicate a
jaroslav@358:  * single choice of license, a recipient has the option to distribute
jaroslav@358:  * your version of this file under either the CDDL, the GPL Version 2 or
jaroslav@358:  * to extend the choice of license to its licensees as provided above.
jaroslav@358:  * However, if you add GPL Version 2 code and therefore, elected the GPL
jaroslav@358:  * Version 2 license, then the option applies only if the new code is
jaroslav@358:  * made subject to such option by the copyright holder.
jaroslav@110:  */
jtulach@838: package org.netbeans.html.context.spi;
jaroslav@110: 
jtulach@1057: import java.lang.annotation.Documented;
jtulach@886: import java.lang.annotation.ElementType;
jtulach@886: import java.lang.annotation.Retention;
jtulach@886: import java.lang.annotation.RetentionPolicy;
jtulach@886: import java.lang.annotation.Target;
jtulach@927: import java.util.HashSet;
jaroslav@574: import java.util.ServiceLoader;
jtulach@927: import java.util.Set;
jaroslav@110: import net.java.html.BrwsrCtx;
jaroslav@362: import org.netbeans.html.context.impl.CtxImpl;
jaroslav@110: 
jaroslav@538: /** Factory class to assign various technologies 
jaroslav@538:  * to a {@link BrwsrCtx browser context}. Start with {@link #newBuilder()}
jaroslav@538:  * and then assign technologies with {@link Builder#register(java.lang.Class, java.lang.Object, int)}
jaroslav@538:  * method.
jaroslav@110:  *
jtulach@655:  * @author Jaroslav Tulach
jaroslav@110:  */
jaroslav@110: public final class Contexts {
jaroslav@110:     private Contexts() {
jaroslav@110:     }
jaroslav@110: 
jaroslav@110:     /** Creates new, empty builder for creation of {@link BrwsrCtx}. At the
jaroslav@534:      * end call the {@link Builder#build()} method to generate the context.
jtulach@886:      * 
jtulach@886:      * @param context instances of various classes or names of {@link Id technologies} 
jtulach@886:      *    to be preferred and used in the built {@link BrwsrCtx context}.
jtulach@886:      * @return new instance of the builder
jtulach@886:      * @since 1.1
jtulach@886:      */
jtulach@886:     public static Builder newBuilder(Object... context) {
jtulach@886:         return new Builder(context);
jtulach@886:     }
jtulach@886:     /** Creates new, empty builder for creation of {@link BrwsrCtx}. At the
jtulach@886:      * end call the {@link Builder#build()} method to generate the context.
jtulach@886:      * Simply calls {@link #newBuilder(java.lang.Object...) newBuilder(new Object[0])}.
jtulach@886:      * 
jaroslav@110:      * @return new instance of the builder
jaroslav@110:      */
jaroslav@110:     public static Builder newBuilder() {
jtulach@886:         return newBuilder(new Object[0]);
jaroslav@110:     }
jaroslav@110: 
jaroslav@110:     /** Seeks for the specified technology in the provided context.
jaroslav@110:      * 
jaroslav@110:      * @param <Tech> type of the technology
jaroslav@110:      * @param context the context to seek in 
jaroslav@110:      *    (previously filled with ({@link Builder#register(java.lang.Class, java.lang.Object, int)})
jaroslav@110:      * @param technology class that identifies the technology
jaroslav@534:      * @return the technology in the context or <code>null</code>
jaroslav@110:      */
jaroslav@110:     public static <Tech> Tech find(BrwsrCtx context, Class<Tech> technology) {
jaroslav@110:         return CtxImpl.find(context, technology);
jaroslav@110:     }
jaroslav@110: 
jaroslav@574:     /** Seeks {@link ServiceLoader} for all registered instances of
jtulach@838:      * {@link Provider} and asks them to {@link Provider#fillContext(org.netbeans.html.context.spi.Contexts.Builder, java.lang.Class) fill
jaroslav@574:      * the builder}.
jaroslav@574:      * 
jaroslav@574:      * @param requestor the application class for which to find the context
jaroslav@574:      * @param cb the context builder to register technologies into
jaroslav@574:      * @return <code>true</code>, if some instances of the provider were
jaroslav@574:      *    found, <code>false</code> otherwise
jaroslav@574:      * @since 0.7.6
jaroslav@574:      */
jaroslav@574:     public static boolean fillInByProviders(Class<?> requestor, Contexts.Builder cb) {
jaroslav@574:         boolean found = false;
jaroslav@574:         ClassLoader l;
jaroslav@574:         try {
jaroslav@574:             l = requestor.getClassLoader();
jaroslav@574:         } catch (SecurityException ex) {
jaroslav@574:             l = null;
jaroslav@574:         }
jtulach@927:         Set<Class<?>> classes = new HashSet<Class<?>>();
jaroslav@574:         for (Provider cp : ServiceLoader.load(Provider.class, l)) {
jtulach@927:             if (!classes.add(cp.getClass())) {
jtulach@927:                 continue;
jtulach@927:             }
jaroslav@574:             cp.fillContext(cb, requestor);
jaroslav@574:             found = true;
jaroslav@574:         }
jaroslav@574:         try {
jaroslav@574:             for (Provider cp : ServiceLoader.load(Provider.class, Provider.class.getClassLoader())) {
jtulach@927:                 if (!classes.add(cp.getClass())) {
jtulach@927:                     continue;
jtulach@927:                 }
jaroslav@574:                 cp.fillContext(cb, requestor);
jaroslav@574:                 found = true;
jaroslav@574:             }
jaroslav@574:         } catch (SecurityException ex) {
jaroslav@574:             if (!found) {
jaroslav@574:                 throw ex;
jaroslav@574:             }
jaroslav@574:         }
jaroslav@574:         if (!found) {
jaroslav@574:             for (Provider cp : ServiceLoader.load(Provider.class)) {
jtulach@927:                 if (!classes.add(cp.getClass())) {
jtulach@927:                     continue;
jtulach@927:                 }
jaroslav@574:                 cp.fillContext(cb, requestor);
jaroslav@574:                 found = true;
jaroslav@574:             }
jaroslav@574:         }
jaroslav@574:         return found;
jaroslav@574:     }
jtulach@886:     
jtulach@886:     /** Identifies the technologies passed to {@link Builder context builder}
jtulach@886:      * by a name. Each implementation of a technology 
jtulach@886:      * {@link Builder#register(java.lang.Class, java.lang.Object, int) registered into a context}
jtulach@886:      * can be annotated with a name (or multiple names). Such implementation
jtulach@886:      * will later be 
jtulach@886:      * {@link Contexts#fillInByProviders(java.lang.Class, org.netbeans.html.context.spi.Contexts.Builder)  preferred during lookup}
jtulach@886:      * if their name(s) has been requested in when 
jtulach@886:      * {@link Contexts#newBuilder(java.lang.Object...)  creating a context}.
jtulach@886:      * @since 1.1
jtulach@886:      */
jtulach@886:     @Retention(RetentionPolicy.RUNTIME)
jtulach@886:     @Target(ElementType.TYPE)
jtulach@1057:     @Documented
jtulach@886:     public @interface Id {
jtulach@904:         /** Identifier(s) for the implementation. 
jtulach@904:          * 
jtulach@904:          * @return one of more identifiers giving this implementation name(s)
jtulach@904:          */
jtulach@886:         public String[] value();
jtulach@886:     }
jaroslav@574: 
jaroslav@110:     /** Implementors of various HTML technologies should
jtulach@790:      * register their implementation via <code>org.openide.util.lookup.ServiceProvider</code>, so
jtulach@790:      * {@link ServiceLoader} can find them, when their JARs are included
jaroslav@110:      * on the classpath of the running application.
jaroslav@110:      *
jtulach@655:      * @author Jaroslav Tulach
jaroslav@110:      */
jaroslav@110:     public static interface Provider {
jaroslav@110: 
jaroslav@110:         /** Register into the context if suitable technology is
jaroslav@110:          * available for the requesting class.
jaroslav@110:          * The provider should check if its own technology is available in current
jaroslav@110:          * scope (e.g. proper JDK, proper browser, etc.). The provider
jaroslav@110:          * can also find the right context depending on requestor's classloader, etc.
jaroslav@110:          * <p>
jaroslav@110:          * Providers should use {@link Builder} to enrich appropriately
jaroslav@110:          * the context.
jaroslav@110:          *
jaroslav@110:          * @param context the context builder to fill with technologies
jaroslav@110:          * @param requestor the application class requesting access the the HTML page
jaroslav@110:          * @see BrwsrCtx#findDefault(java.lang.Class)
jaroslav@110:          */
jaroslav@110:         void fillContext(Builder context, Class<?> requestor);
jaroslav@110:     }
jaroslav@110: 
jaroslav@110:     /** Support for providers of new {@link BrwsrCtx}. Providers of different
jaroslav@110:      * technologies should be of particular interest in this class. End users
jaroslav@110:      * designing their application with existing technologies should rather
jaroslav@110:      * point their attention to {@link BrwsrCtx} and co.
jaroslav@110:      *
jtulach@655:      * @author Jaroslav Tulach
jaroslav@110:      */
jaroslav@110:     public static final class Builder {
jtulach@886:         private final CtxImpl impl;
jaroslav@110: 
jtulach@886:         public Builder(Object[] context) {
jtulach@886:             this.impl = new CtxImpl(context);
jaroslav@110:         }
jaroslav@110:         
jaroslav@110:         /** Registers new technology into the context. Each technology is
jaroslav@110:          * exactly identified by its implementation class and can be associated
jaroslav@110:          * with (positive) priority. In case of presence of multiple technologies
jaroslav@110:          * with the same class, the one with higher lower priority takes precedence.
jaroslav@256:          * @param <Tech> type of technology to register
jaroslav@256:          * @param type the real class of the technology type
jaroslav@256:          * @param impl an instance of the technology class
jaroslav@256:          * @param position the lower position, the more important implementation 
jaroslav@256:          *    which will be consulted sooner when seeking for a {@link Contexts#find(net.java.html.BrwsrCtx, java.lang.Class)}
jaroslav@256:          *    an implementation
jaroslav@256:          * @return this builder
jaroslav@110:          */
jaroslav@256:         public <Tech> Builder register(Class<Tech> type, Tech impl, int position) {
jaroslav@589:             if (impl == null) {
jaroslav@589:                 return this;
jaroslav@589:             }
jaroslav@256:             if (position <= 0) {
jaroslav@110:                 throw new IllegalStateException();
jaroslav@110:             }
jaroslav@256:             this.impl.register(type, impl, position);
jaroslav@110:             return this;
jaroslav@110:         }
jaroslav@110: 
jaroslav@110:         /** Generates context based on values previously inserted into
jaroslav@110:          * this builder.
jaroslav@110:          *
jaroslav@110:          * @return new, immutable instance of {@link BrwsrCtx}
jaroslav@110:          */
jaroslav@110:         public BrwsrCtx build() {
jaroslav@110:             return impl.build();
jaroslav@110:         }
jaroslav@110:     }
jaroslav@110: }