MERGE PREP: Introduced base interface "Resource" to allow basic lookup API to be consolidated in ResourceSet.

Approach copied from "master".

Author: rickbw

src/main/java/crud/core/ReadableResource.java

@@ -29,7 +29,7 @@
  *
  * @author Rick Warren
  */
-public interface ReadableResource<E> extends AsyncCloseable {
+public interface ReadableResource<E> extends Resource {
 
     /**
      * Begin observation of the data elements. The {@link Observable} may be

src/main/java/crud/core/ReadableResourceSet.java

@@ -39,6 +39,7 @@ public interface ReadableResourceSet<K, E> extends ResourceSet<K, E> {
      *              obtained from a {@link DataBus} compatible with this
      *              {@link ReadableResourceSet}.
      */
+    @Override
     public @Nonnull ReadableResource<E> resource(@Nonnull K key, @Nonnull Session session);
 
 

src/main/java/crud/core/Resource.java

@@ -0,0 +1,27 @@
+/* Copyright 2015 Rick Warren
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package crud.core;
+
+
+/**
+ * An abstract stateful entity, whose value may be retrieved via the
+ * sub-interface {@link ReadableResource}, or modified via the sub-interface
+ * {@link WritableResource}.
+ *
+ * @author Rick Warren
+ */
+public interface Resource extends AsyncCloseable {
+    // empty
+}

src/main/java/crud/core/ResourceSet.java

@@ -38,6 +38,16 @@ public interface ResourceSet<K, E> {
      */
     public @Nonnull Id<K, E> getId();
 
+    /**
+     * Return a {@link Resource} identified by the given key, to be accessed
+     * in the context of the given {@link Session}.
+     *
+     * @throws ClassCastException               If the {@link Session} was not
+     *              obtained from a {@link DataBus} compatible with this
+     *              {@link WritableResourceSet}.
+     */
+    public @Nonnull Resource resource(@Nonnull K key, @Nonnull Session session);
+
 
     /**
      * Identifies a {@link ResourceSet}: a named collection of homogeneously-typed

src/main/java/crud/core/WritableResource.java

@@ -29,7 +29,7 @@
  *
  * @author Rick Warren
  */
-public interface WritableResource<E, R> extends AsyncCloseable {
+public interface WritableResource<E, R> extends Resource {
 
     /**
      * Write a single data element to the target middleware. Return to the

src/main/java/crud/core/WritableResourceSet.java

@@ -40,9 +40,8 @@ public interface WritableResourceSet<K, E, R> extends ResourceSet<K, E> {
      * @throws ClassCastException               If the {@link Session} was not
      *              obtained from a {@link DataBus} compatible with this
      *              {@link WritableResourceSet}.
-     * @throws UnsupportedOperationException    If this {@link WritableResourceSet} cannot
-     *              be written.
      */
+    @Override
     public @Nonnull WritableResource<E, R> resource(@Nonnull K key, @Nonnull Session session);
 
 

src/main/java/crud/sync/SyncReadableResource.java

@@ -17,15 +17,14 @@
 import javax.annotation.Nonnull;
 
 import crud.core.ReadableResource;
-import crud.implementer.AsyncResults;
 
 
 /**
  * @see ReadableResource
  *
  * @author Rick Warren
  */
-public class SyncReadableResource<E> extends SyncDelegateHolder<ReadableResource<E>> implements AutoCloseable {
+public class SyncReadableResource<E> extends SyncResource<ReadableResource<E>> {
 
     public SyncReadableResource(@Nonnull final ReadableResource<E> delegate) {
         super(delegate);
@@ -38,12 +37,4 @@ public Iterable<E> read() {
         return getDelegate().read().toBlocking().toIterable();
     }
 
-    /**
-     * @see ReadableResource#shutdown()
-     */
-    @Override
-    public void close() throws Exception {
-        AsyncResults.awaitShutdown(getDelegate());
-    }
-
 }

src/main/java/crud/sync/SyncReadableResourceSet.java

@@ -18,7 +18,6 @@
 
 import crud.core.ReadableResource;
 import crud.core.ReadableResourceSet;
-import crud.core.ReadableResourceSet.Id;
 import crud.core.Session;
 
 
@@ -27,7 +26,7 @@
  *
  * @author Rick Warren
  */
-public class SyncReadableResourceSet<K, E> extends SyncDelegateHolder<ReadableResourceSet<K, E>> {
+public class SyncReadableResourceSet<K, E> extends SyncResourceSet<K, E, ReadableResourceSet<K, E>> {
 
     public SyncReadableResourceSet(@Nonnull final ReadableResourceSet<K, E> delegate) {
         super(delegate);
@@ -36,13 +35,15 @@ public SyncReadableResourceSet(@Nonnull final ReadableResourceSet<K, E> delegate
     /**
      * @see ReadableResourceSet#getId()
      */
-    public @Nonnull Id<K, E> getId() {
+    @Override
+    public @Nonnull ReadableResourceSet.Id<K, E> getId() {
         return getDelegate().getId();
     }
 
     /**
      * @see ReadableResourceSet#resource(Object, Session)
      */
+    @Override
     public @Nonnull SyncReadableResource<E> resource(@Nonnull final K key, @Nonnull final SyncSession session) {
         final ReadableResource<E> delegateSource = getDelegate().resource(key, session.getDelegate());
         return new SyncReadableResource<>(delegateSource);

src/main/java/crud/sync/SyncResource.java

@@ -0,0 +1,37 @@
+/* Copyright 2015 Rick Warren
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package crud.sync;
+
+import crud.core.Resource;
+import crud.implementer.AsyncResults;
+
+
+public abstract class SyncResource<D extends Resource>
+extends SyncDelegateHolder<D>
+implements AutoCloseable {
+
+    /**
+     * @see Resource#shutdown()
+     */
+    @Override
+    public final void close() throws Exception {
+        AsyncResults.awaitShutdown(getDelegate());
+    }
+
+    /*package*/ SyncResource(final D delegate) {
+        super(delegate);
+    }
+
+}

src/main/java/crud/sync/SyncResourceSet.java

@@ -0,0 +1,45 @@
+/* Copyright 2015 Rick Warren
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package crud.sync;
+
+import javax.annotation.Nonnull;
+
+import crud.core.ResourceSet;
+import crud.core.Session;
+
+
+/**
+ * @see ResourceSet
+ */
+public abstract class SyncResourceSet<K, E, D extends ResourceSet<K, E>>
+extends SyncDelegateHolder<D> {
+
+    /**
+     * @see ResourceSet#getId()
+     */
+    public abstract @Nonnull ResourceSet.Id<K, E> getId();
+
+    /**
+     * @see ResourceSet#resource(Object, Session)
+     */
+    public abstract @Nonnull SyncResource<?> resource(
+            @Nonnull final K key,
+            @Nonnull final SyncSession session);
+
+    /*package*/ SyncResourceSet(final D delegate) {
+        super(delegate);
+    }
+
+}