Added DelegateStorableGenerator.

3 files changed, 188 insertions, 0 deletions

diff --git a/src/main/java/com/amazon/carbonado/gen/DelegateStorableGenerator.java b/src/main/java/com/amazon/carbonado/gen/DelegateStorableGenerator.java
new file mode 100644
index 0000000..4de28bd
--- /dev/null
+++ b/src/main/java/com/amazon/carbonado/gen/DelegateStorableGenerator.java
@@ -0,0 +1,149 @@
+/*

+ * Copyright 2008 Amazon Technologies, Inc. or its affiliates.

+ * Amazon, Amazon.com and Carbonado are trademarks or registered trademarks

+ * of Amazon Technologies, Inc. or its affiliates.  All rights reserved.

+ *

+ * 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 com.amazon.carbonado.gen;

+

+import java.util.EnumSet;

+import java.util.Map;

+

+import org.cojen.classfile.ClassFile;

+import org.cojen.classfile.CodeBuilder;

+import org.cojen.classfile.MethodInfo;

+import org.cojen.classfile.Modifiers;

+import org.cojen.classfile.TypeDesc;

+

+import org.cojen.util.ClassInjector;

+import org.cojen.util.KeyFactory;

+import org.cojen.util.SoftValuedHashMap;

+

+import com.amazon.carbonado.Storable;

+import com.amazon.carbonado.SupportException;

+

+/**

+ * Generates and caches concrete implementations of {@link Storable} types

+ * which delegate to {@link DelegateSupport}. The delegating classes extend

+ * those generated by {@link MasterStorableGenerator}.

+ *

+ * @author Brian S O'Neill

+ * @since 1.2

+ */

+public class DelegateStorableGenerator<S extends Storable> {

+    private static final Map<Object, Class> cCache;

+

+    static {

+        cCache = new SoftValuedHashMap();

+    }

+

+    /**

+     * Delegate class has a constructor that accepts a {@link DelegateSupport}

+     * instance.

+     *

+     * <pre>

+     * public &lt;init&gt;(DelegateSupport);

+     * </pre>

+     * 

+     */

+    public static <S extends Storable> Class<? extends S>

+        getDelegateClass(Class<S> type, EnumSet<MasterFeature> features)

+        throws SupportException

+    {

+        Object key = KeyFactory.createKey(new Object[] {type, features});

+

+        synchronized (cCache) {

+            Class<? extends S> generatedClass = (Class<? extends S>) cCache.get(key);

+            if (generatedClass != null) {

+                return generatedClass;

+            }

+            generatedClass = new DelegateStorableGenerator<S>(type, features)

+                .generateAndInjectClass();

+            cCache.put(key, generatedClass);

+            return generatedClass;

+        }

+    }

+

+    private final Class<S> mStorableType;

+

+    private final ClassInjector mClassInjector;

+    private final ClassFile mClassFile;

+

+    private DelegateStorableGenerator(Class<S> type, EnumSet<MasterFeature> features)

+        throws SupportException

+    {

+        mStorableType = type;

+

+        final Class<? extends S> abstractClass =

+            MasterStorableGenerator.getAbstractClass(mStorableType, features);

+

+        mClassInjector = ClassInjector.create(mStorableType.getName(),

+                                              abstractClass.getClassLoader());

+

+        mClassFile = new ClassFile(mClassInjector.getClassName(), abstractClass);

+        mClassFile.markSynthetic();

+        mClassFile.setSourceFile(DelegateStorableGenerator.class.getName());

+        mClassFile.setTarget("1.5");

+    }

+

+    private Class<? extends S> generateAndInjectClass() {

+        TypeDesc masterSupportType = TypeDesc.forClass(MasterSupport.class);

+        TypeDesc delegateSupportType = TypeDesc.forClass(DelegateSupport.class);

+

+        // Add constructor that accepts a DelegateSupport.

+        {

+            TypeDesc[] params = {delegateSupportType};

+            MethodInfo mi = mClassFile.addConstructor(Modifiers.PUBLIC, params);

+            CodeBuilder b = new CodeBuilder(mi);

+            b.loadThis();

+            b.loadLocal(b.getParameter(0));

+            b.invokeSuperConstructor(new TypeDesc[] {masterSupportType});

+            b.returnVoid();

+        }

+

+        // Implement abstract methods which all delegate to DelegateSupport instance.

+

+        generateDelegatedMethod

+            (MasterStorableGenerator.DO_TRY_LOAD_MASTER_METHOD_NAME, "doTryLoad");

+        generateDelegatedMethod

+            (MasterStorableGenerator.DO_TRY_INSERT_MASTER_METHOD_NAME, "doTryInsert");

+        generateDelegatedMethod

+            (MasterStorableGenerator.DO_TRY_UPDATE_MASTER_METHOD_NAME, "doTryUpdate");

+        generateDelegatedMethod

+            (MasterStorableGenerator.DO_TRY_DELETE_MASTER_METHOD_NAME, "doTryDelete");

+

+        Class<? extends S> generatedClass = mClassInjector.defineClass(mClassFile);

+

+        return generatedClass;

+    }

+

+    private void generateDelegatedMethod(String masterMethodName, String supportMethodName) {

+        TypeDesc triggerSupportType = TypeDesc.forClass(TriggerSupport.class);

+        TypeDesc delegateSupportType = TypeDesc.forClass(DelegateSupport.class);

+

+        TypeDesc[] storableParam = {TypeDesc.forClass(Storable.class)};

+

+        MethodInfo mi = mClassFile.addMethod

+            (Modifiers.PROTECTED, masterMethodName, TypeDesc.BOOLEAN, null);

+        CodeBuilder b = new CodeBuilder(mi);

+

+        b.loadThis();

+        b.loadField(StorableGenerator.SUPPORT_FIELD_NAME, triggerSupportType);

+        b.checkCast(delegateSupportType);

+        b.loadThis();

+        b.invokeInterface(delegateSupportType, supportMethodName, TypeDesc.BOOLEAN, storableParam);

+        b.returnValue(TypeDesc.BOOLEAN);

+    }

+}

diff --git a/src/main/java/com/amazon/carbonado/gen/DelegateSupport.java b/src/main/java/com/amazon/carbonado/gen/DelegateSupport.java
new file mode 100644
index 0000000..31f0288
--- /dev/null
+++ b/src/main/java/com/amazon/carbonado/gen/DelegateSupport.java
@@ -0,0 +1,38 @@
+/*

+ * Copyright 2008 Amazon Technologies, Inc. or its affiliates.

+ * Amazon, Amazon.com and Carbonado are trademarks or registered trademarks

+ * of Amazon Technologies, Inc. or its affiliates.  All rights reserved.

+ *

+ * 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 com.amazon.carbonado.gen;

+

+import com.amazon.carbonado.Storable;

+

+/**

+ * Provides runtime support for Storable classes generated by {@link DelegateStorableGenerator}.

+ *

+ * @author Brian S O'Neill

+ * @since 1.2

+ */

+public interface DelegateSupport<S extends Storable> extends MasterSupport<S> {

+    boolean doTryLoad(S storable);

+

+    boolean doTryInsert(S storable);

+

+    boolean doTryUpdate(S storable);

+

+    boolean doTryDelete(S storable);

+}

+

diff --git a/src/main/java/com/amazon/carbonado/gen/StorableGenerator.java b/src/main/java/com/amazon/carbonado/gen/StorableGenerator.java
index 5c8c93d..711ee58 100644
--- a/src/main/java/com/amazon/carbonado/gen/StorableGenerator.java
+++ b/src/main/java/com/amazon/carbonado/gen/StorableGenerator.java
@@ -78,6 +78,7 @@ import static com.amazon.carbonado.gen.CommonMethodNames.*;
  * @author Brian S O'Neill

  * @author Don Schneider

  * @see MasterStorableGenerator

+ * @see DelegateStorableGenerator

  * @since 1.2

  */

 public final class StorableGenerator<S extends Storable> {