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Posted to commits@cayenne.apache.org by aa...@apache.org on 2009/11/21 21:40:27 UTC

svn commit: r882988 - in /cayenne/sandbox/cayenne-di/src: main/java/org/apache/cayenne/di/spi/ test/java/org/apache/cayenne/di/mock/ test/java/org/apache/cayenne/di/spi/

Author: aadamchik
Date: Sat Nov 21 20:40:26 2009
New Revision: 882988

URL: http://svn.apache.org/viewvc?rev=882988&view=rev
Log:
playing with DI ideas

* fixing circular dependency during constructor injection

Added:
    cayenne/sandbox/cayenne-di/src/test/java/org/apache/cayenne/di/mock/MockImplementation1_DepOn2Constructor.java
    cayenne/sandbox/cayenne-di/src/test/java/org/apache/cayenne/di/mock/MockImplementation2_Constructor.java
Modified:
    cayenne/sandbox/cayenne-di/src/main/java/org/apache/cayenne/di/spi/ConstructorProvider.java
    cayenne/sandbox/cayenne-di/src/main/java/org/apache/cayenne/di/spi/FieldInjectingProvider.java
    cayenne/sandbox/cayenne-di/src/main/java/org/apache/cayenne/di/spi/InjectionStack.java
    cayenne/sandbox/cayenne-di/src/test/java/org/apache/cayenne/di/spi/DefaultInjectorCircularInjectionTest.java

Modified: cayenne/sandbox/cayenne-di/src/main/java/org/apache/cayenne/di/spi/ConstructorProvider.java
URL: http://svn.apache.org/viewvc/cayenne/sandbox/cayenne-di/src/main/java/org/apache/cayenne/di/spi/ConstructorProvider.java?rev=882988&r1=882987&r2=882988&view=diff
==============================================================================
--- cayenne/sandbox/cayenne-di/src/main/java/org/apache/cayenne/di/spi/ConstructorProvider.java (original)
+++ cayenne/sandbox/cayenne-di/src/main/java/org/apache/cayenne/di/spi/ConstructorProvider.java Sat Nov 21 20:40:26 2009
@@ -26,17 +26,16 @@
 
 import org.apache.cayenne.di.DIException;
 import org.apache.cayenne.di.Inject;
-import org.apache.cayenne.di.Injector;
 import org.apache.cayenne.di.Provider;
 
 class ConstructorProvider<T> implements Provider<T> {
 
     private Class<T> interfaceType;
     private Constructor<? extends T> constructor;
-    private Injector injector;
+    private DefaultInjector injector;
 
     ConstructorProvider(Class<T> interfaceType, Class<? extends T> implementation,
-            Injector injector) {
+            DefaultInjector injector) {
 
         initConstructor(implementation);
 
@@ -106,6 +105,7 @@
         Class<?>[] constructorParameters = constructor.getParameterTypes();
         Type[] genericTypes = constructor.getGenericParameterTypes();
         Object[] args = new Object[constructorParameters.length];
+        InjectionStack stack = injector.getInjectionStack();
 
         for (int i = 0; i < constructorParameters.length; i++) {
 
@@ -138,7 +138,14 @@
                 args[i] = injector.getProvider(objectClass);
             }
             else {
-                args[i] = injector.getInstance(parameter);
+
+                stack.push(DIUtil.toKey(parameter));
+                try {
+                    args[i] = injector.getInstance(parameter);
+                }
+                finally {
+                    stack.pop();
+                }
             }
         }
 

Modified: cayenne/sandbox/cayenne-di/src/main/java/org/apache/cayenne/di/spi/FieldInjectingProvider.java
URL: http://svn.apache.org/viewvc/cayenne/sandbox/cayenne-di/src/main/java/org/apache/cayenne/di/spi/FieldInjectingProvider.java?rev=882988&r1=882987&r2=882988&view=diff
==============================================================================
--- cayenne/sandbox/cayenne-di/src/main/java/org/apache/cayenne/di/spi/FieldInjectingProvider.java (original)
+++ cayenne/sandbox/cayenne-di/src/main/java/org/apache/cayenne/di/spi/FieldInjectingProvider.java Sat Nov 21 20:40:26 2009
@@ -71,51 +71,51 @@
                 object.getClass(),
                 new ArrayList<Field>());
 
-        injector.getInjectionStack().push(bindingKey);
+        InjectionStack stack = injector.getInjectionStack();
 
-        try {
+        for (Field field : injectableFields) {
+            Object value;
+            Class<?> fieldType = field.getType();
 
-            for (Field field : injectableFields) {
-                Object value;
-                Class<?> fieldType = field.getType();
-
-                if (Provider.class.equals(fieldType)) {
-
-                    Class<?> objectClass = DIUtil.parameterClass(field
-                            .getGenericType());
-
-                    if (objectClass == null) {
-                        String message = String.format(
-                                "Provider field %s.%s of type %s must be "
-                                        + "parameterized to be usable for injection",
-                                field.getDeclaringClass().getName(),
-                                field.getName(),
-                                fieldType.getName());
-                        throw new DIException(message);
-                    }
+            if (Provider.class.equals(fieldType)) {
 
-                    value = injector.getProvider(objectClass);
-                }
-                else {
-                    value = injector.getInstance(fieldType);
-                }
+                Class<?> objectClass = DIUtil.parameterClass(field.getGenericType());
 
-                try {
-                    field.set(object, value);
-                }
-                catch (Exception e) {
+                if (objectClass == null) {
                     String message = String.format(
-                            "Error injecting into field %s.%s of type %s",
+                            "Provider field %s.%s of type %s must be "
+                                    + "parameterized to be usable for injection",
                             field.getDeclaringClass().getName(),
                             field.getName(),
                             fieldType.getName());
-                    throw new DIException(message, e);
+                    throw new DIException(message);
                 }
+
+                value = injector.getProvider(objectClass);
+            }
+            else {
+                stack.push(bindingKey);
+                try {
+                    value = injector.getInstance(fieldType);
+                }
+                finally {
+                    stack.pop();
+                }
+            }
+
+            try {
+                field.set(object, value);
+            }
+            catch (Exception e) {
+                String message = String.format(
+                        "Error injecting into field %s.%s of type %s",
+                        field.getDeclaringClass().getName(),
+                        field.getName(),
+                        fieldType.getName());
+                throw new DIException(message, e);
             }
         }
-        finally {
-            injector.getInjectionStack().pop();
-        }
+
     }
 
 }

Modified: cayenne/sandbox/cayenne-di/src/main/java/org/apache/cayenne/di/spi/InjectionStack.java
URL: http://svn.apache.org/viewvc/cayenne/sandbox/cayenne-di/src/main/java/org/apache/cayenne/di/spi/InjectionStack.java?rev=882988&r1=882987&r2=882988&view=diff
==============================================================================
--- cayenne/sandbox/cayenne-di/src/main/java/org/apache/cayenne/di/spi/InjectionStack.java (original)
+++ cayenne/sandbox/cayenne-di/src/main/java/org/apache/cayenne/di/spi/InjectionStack.java Sat Nov 21 20:40:26 2009
@@ -49,9 +49,13 @@
         }
 
         if (localStack.contains(bindingKey)) {
-            throw new DIException("Circular dependency detected: "
-                    + localStack
-                    + ". You should try injecting a provider instead.");
+            String message = String
+                    .format(
+                            "Circular dependency detected when binding a key \"%s\". Nested keys: %s"
+                                    + ". To resolve it, you should inject a Provider instead of an object.",
+                            bindingKey,
+                            localStack);
+            throw new DIException(message);
         }
 
         localStack.add(bindingKey);

Added: cayenne/sandbox/cayenne-di/src/test/java/org/apache/cayenne/di/mock/MockImplementation1_DepOn2Constructor.java
URL: http://svn.apache.org/viewvc/cayenne/sandbox/cayenne-di/src/test/java/org/apache/cayenne/di/mock/MockImplementation1_DepOn2Constructor.java?rev=882988&view=auto
==============================================================================
--- cayenne/sandbox/cayenne-di/src/test/java/org/apache/cayenne/di/mock/MockImplementation1_DepOn2Constructor.java (added)
+++ cayenne/sandbox/cayenne-di/src/test/java/org/apache/cayenne/di/mock/MockImplementation1_DepOn2Constructor.java Sat Nov 21 20:40:26 2009
@@ -0,0 +1,36 @@
+/*****************************************************************
+ *   Licensed to the Apache Software Foundation (ASF) under one
+ *  or more contributor license agreements.  See the NOTICE file
+ *  distributed with this work for additional information
+ *  regarding copyright ownership.  The ASF licenses this file
+ *  to you 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 org.apache.cayenne.di.mock;
+
+import org.apache.cayenne.di.Inject;
+
+public class MockImplementation1_DepOn2Constructor implements MockInterface1 {
+
+    private MockInterface2 interface2;
+
+    // this creates a circular dependency when MockImplementation2 is bound to
+    // MockInterface2.
+    public MockImplementation1_DepOn2Constructor(@Inject MockInterface2 interface2) {
+        this.interface2 = interface2;
+    }
+
+    public String getName() {
+        return interface2.getName();
+    }
+}

Added: cayenne/sandbox/cayenne-di/src/test/java/org/apache/cayenne/di/mock/MockImplementation2_Constructor.java
URL: http://svn.apache.org/viewvc/cayenne/sandbox/cayenne-di/src/test/java/org/apache/cayenne/di/mock/MockImplementation2_Constructor.java?rev=882988&view=auto
==============================================================================
--- cayenne/sandbox/cayenne-di/src/test/java/org/apache/cayenne/di/mock/MockImplementation2_Constructor.java (added)
+++ cayenne/sandbox/cayenne-di/src/test/java/org/apache/cayenne/di/mock/MockImplementation2_Constructor.java Sat Nov 21 20:40:26 2009
@@ -0,0 +1,38 @@
+/*****************************************************************
+ *   Licensed to the Apache Software Foundation (ASF) under one
+ *  or more contributor license agreements.  See the NOTICE file
+ *  distributed with this work for additional information
+ *  regarding copyright ownership.  The ASF licenses this file
+ *  to you 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 org.apache.cayenne.di.mock;
+
+import org.apache.cayenne.di.Inject;
+
+public class MockImplementation2_Constructor implements MockInterface2 {
+
+    private MockInterface1 service;
+
+    public MockImplementation2_Constructor(@Inject MockInterface1 service) {
+        this.service = service;
+    }
+
+    public String getAlteredName() {
+        return "altered_" + service.getName();
+    }
+
+    public String getName() {
+        return "MockImplementation2Name";
+    }
+}

Modified: cayenne/sandbox/cayenne-di/src/test/java/org/apache/cayenne/di/spi/DefaultInjectorCircularInjectionTest.java
URL: http://svn.apache.org/viewvc/cayenne/sandbox/cayenne-di/src/test/java/org/apache/cayenne/di/spi/DefaultInjectorCircularInjectionTest.java?rev=882988&r1=882987&r2=882988&view=diff
==============================================================================
--- cayenne/sandbox/cayenne-di/src/test/java/org/apache/cayenne/di/spi/DefaultInjectorCircularInjectionTest.java (original)
+++ cayenne/sandbox/cayenne-di/src/test/java/org/apache/cayenne/di/spi/DefaultInjectorCircularInjectionTest.java Sat Nov 21 20:40:26 2009
@@ -24,8 +24,10 @@
 import org.apache.cayenne.di.DIException;
 import org.apache.cayenne.di.Module;
 import org.apache.cayenne.di.mock.MockImplementation1_DepOn2;
+import org.apache.cayenne.di.mock.MockImplementation1_DepOn2Constructor;
 import org.apache.cayenne.di.mock.MockImplementation1_DepOn2Provider;
 import org.apache.cayenne.di.mock.MockImplementation2;
+import org.apache.cayenne.di.mock.MockImplementation2_Constructor;
 import org.apache.cayenne.di.mock.MockInterface1;
 import org.apache.cayenne.di.mock.MockInterface2;
 
@@ -71,4 +73,30 @@
         MockInterface1 service = injector.getInstance(MockInterface1.class);
         assertEquals("MockImplementation2Name", service.getName());
     }
+
+    public void testConstructorInjection_CircularDependency() {
+
+        Module module = new Module() {
+
+            public void configure(Binder binder) {
+                binder.bind(MockInterface1.class).to(
+                        MockImplementation1_DepOn2Constructor.class);
+                binder.bind(MockInterface2.class).to(
+                        MockImplementation2_Constructor.class);
+            }
+        };
+
+        DefaultInjector injector = new DefaultInjector(module);
+
+        try {
+            injector.getInstance(MockInterface1.class);
+            fail("Circular dependency is not detected.");
+        }
+        catch (DIException e) {
+            // expected
+        }
+        catch (StackOverflowError e) {
+            fail("Circular dependency is not detected, causing stack overflow");
+        }
+    }
 }