Injector: Separate @Inject into two annotations for clarity

common/injector/src/main/java/com/speedment/common/injector/annotation/Inject.java

@@ -16,7 +16,6 @@
  */
 package com.speedment.common.injector.annotation;
 
-import com.speedment.common.injector.State;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Inherited;
 import java.lang.annotation.Retention;
@@ -25,36 +24,11 @@
 
 /**
  * Annotes a field that should be set automatically using dependency injection.
- * Each injected field has a specified state that it is required to be in. It
- * is up to the injector to make sure that a type has been properly setup.
  * 
  * @author  Emil Forslund
  * @since   1.0.0
  */
 @Inherited
-@Target({ElementType.FIELD, ElementType.PARAMETER})
+@Target({ElementType.FIELD})
 @Retention(RetentionPolicy.RUNTIME)
-public @interface Inject {
-
-    /**
-     * The {@link State} that the injected value must be in before 
-     * it can be injected.
-     * <p>
-     * The default state is {@link State#STARTED}.
-     * 
-     * @return  the expected phase of the injected component
-     */
-    State value() default State.STARTED;
-
-    /**
-     * If the injector should throw an exception if no implementation
-     * for this value could be found. If {@code required} is false, then
-     * the value will simply be set to null.
-     * <p>
-     * The default is that every injected value is required.
-     * 
-     * @return  if this value is required
-     */
-    boolean required() default true;
-
-}
+public @interface Inject {}

common/injector/src/main/java/com/speedment/common/injector/annotation/WithState.java

@@ -0,0 +1,47 @@
+/**
+ *
+ * Copyright (c) 2006-2016, Speedment, Inc. 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.speedment.common.injector.annotation;
+
+import com.speedment.common.injector.State;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Inherited;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Annotes that the method parameter should be set to 
+ * something with a certain state.
+ * 
+ * @author  Emil Forslund
+ * @since   1.0.0
+ */
+@Inherited
+@Target(ElementType.PARAMETER)
+@Retention(RetentionPolicy.RUNTIME)
+public @interface WithState {
+
+    /**
+     * The {@link State} that the injected value must be in before 
+     * it can be injected.
+     * <p>
+     * The default state is {@link State#CREATED}.
+     * 
+     * @return  the expected phase of the injected component
+     */
+    State value() default State.CREATED;
+}

common/injector/src/main/java/com/speedment/common/injector/internal/InjectorImpl.java

@@ -53,6 +53,7 @@
 import java.util.Optional;
 import java.util.Properties;
 import com.speedment.common.injector.annotation.IncludeInjectable;
+import com.speedment.common.injector.annotation.WithState;
 import com.speedment.common.logger.Logger;
 import com.speedment.common.logger.LoggerManager;
 import java.util.LinkedHashMap;
@@ -128,7 +129,7 @@ public void stop() {
                             .map(Execution::getMethod)
                             .forEach(m -> {
                                 final Object[] params = Stream.of(m.getParameters())
-                                    .map(p -> findIn(p.getType(), p.getAnnotation(Inject.class).required()))
+                                    .map(p -> findIn(p.getType(), p.getAnnotation(WithState.class) != null))
                                     .toArray(Object[]::new);
 
                                 m.setAccessible(true);
@@ -222,7 +223,7 @@ private <T> void injectFields(T instance) {
             if (Injector.class.isAssignableFrom(field.getType())) {
                 value = this;
             } else {
-                value = findIn(field.getType(), field.getAnnotation(Inject.class).required());
+                value = findIn(field.getType(), field.getAnnotation(WithState.class) != null);
             }
 
             field.setAccessible(true);
@@ -332,7 +333,7 @@ public Injector build() throws InstantiationException, NoDefaultConstructorExcep
                     if (Inject.class.isAssignableFrom(field.getType())) {
                         value = injector;
                     } else {
-                        value = findIn(injector, field.getType(), instances, field.getAnnotation(Inject.class).required());
+                        value = findIn(injector, field.getType(), instances, field.getAnnotation(WithState.class) != null);
                     }
 
                     field.setAccessible(true);
@@ -379,7 +380,7 @@ public Injector build() throws InstantiationException, NoDefaultConstructorExcep
                                 .map(Execution::getMethod)
                                 .forEach(m -> {
                                     final Object[] params = Stream.of(m.getParameters())
-                                        .map(p -> findIn(injector, p.getType(), instances, p.getAnnotation(Inject.class).required()))
+                                        .map(p -> findIn(injector, p.getType(), instances, p.getAnnotation(WithState.class) != null))
                                         .toArray(Object[]::new);
 
                                     m.setAccessible(true);

common/injector/src/main/java/com/speedment/common/injector/internal/dependency/impl/DependencyGraphImpl.java

@@ -18,15 +18,14 @@
 
 import com.speedment.common.injector.annotation.Execute;
 import com.speedment.common.injector.annotation.ExecuteBefore;
-import com.speedment.common.injector.annotation.Inject;
 import com.speedment.common.injector.exception.CyclicReferenceException;
 import com.speedment.common.injector.internal.dependency.Dependency;
 import com.speedment.common.injector.internal.dependency.DependencyGraph;
 import com.speedment.common.injector.internal.dependency.DependencyNode;
 import com.speedment.common.injector.internal.dependency.Execution;
-import static com.speedment.common.injector.internal.util.ReflectionUtil.traverseFields;
 import static com.speedment.common.injector.internal.util.ReflectionUtil.traverseMethods;
 import com.speedment.common.injector.State;
+import com.speedment.common.injector.annotation.WithState;
 import com.speedment.common.injector.internal.InjectorImpl;
 import java.lang.reflect.Method;
 import java.lang.reflect.Parameter;
@@ -81,10 +80,6 @@ public DependencyNode getOrCreate(Class<?> clazz) {
     @Override
     public DependencyGraph inject() {
         nodes.forEach((clazz, node) -> {
-            // Go through all the member variables with the '@Inject'-annotation in the 
-            // class and add edges to them in the dependency graph.
-            addDependenciesTo(clazz, node.getDependencies());
-
             // Go through all the methods with the '@Execute'-annotation in the class and
             // add them to the executors set.
             traverseMethods(clazz)
@@ -120,55 +115,26 @@ private static String methodName(Method m) {
             ")";
     }
 
-    private void addDependenciesTo(Class<?> clazz, Set<Dependency> dependencies) {
-        traverseFields(clazz)
-            .filter(f -> f.isAnnotationPresent(Inject.class))
-            .forEach(f -> {
-
-                final Inject inject = f.getAnnotation(Inject.class);
-                final Class<?> type = f.getType();
-                final State state   = inject.value();
-
-                try {
-                    dependencies.add(
-                        new DependencyImpl(get(type), state)
-                    );
-                } catch (final IllegalArgumentException ex) {
-                    throw new IllegalStateException(
-                        "Class " + clazz.getSimpleName() + 
-                        " requested field " + type.getSimpleName() + 
-                        " to be injected, but it was not found. Available components: [" +
-                        nodes.keySet().stream()
-                            .map(Class::getSimpleName)
-                            .collect(joining(",\n    ", "\n    ", "\n")) +
-                        "].", 
-                        ex
-                    );
-                }
-            });
-    }
-
     private Execution createExecution(Class<?> clazz, Method m, State executeBefore) {
 
         // Make sure all the methods parameters are annoted with the 
-        // '@Inject'-annotation.
+        // '@WithState'-annotation.
         if (Stream.of(m.getParameters())
-            .anyMatch(p -> !p.isAnnotationPresent(Inject.class))) {
+            .anyMatch(p -> !p.isAnnotationPresent(WithState.class))) {
             throw new RuntimeException(
                 "Method '" + methodName(m) + 
                 "' has a parameter that is missing the @" + 
-                Inject.class.getSimpleName() + " annotation."
+                WithState.class.getSimpleName() + " annotation."
             );
         }
 
-
         final Set<Dependency> dependencies = new HashSet<>();
         try {
             for (int i = 0; i < m.getParameterCount(); i++) {
                 final Parameter p   = m.getParameters()[i];
-                final Inject inject = p.getAnnotation(Inject.class);
+                final WithState ws  = p.getAnnotation(WithState.class);
                 final Class<?> type = p.getType();
-                final State state   = inject.value();
+                final State state   = ws.value();
 
                 try {
                     dependencies.add(
@@ -185,8 +151,6 @@ private Execution createExecution(Class<?> clazz, Method m, State executeBefore)
                 ex
             );
         }
-
-        addDependenciesTo(clazz, dependencies);
 
         return new ExecutionImpl(executeBefore, m, dependencies);
     }

common/injector/src/test/java/com/speedment/common/injector/test_a/StringIdentityMapper.java

@@ -18,7 +18,7 @@
 
 import static com.speedment.common.injector.State.RESOLVED;
 import com.speedment.common.injector.annotation.ExecuteBefore;
-import com.speedment.common.injector.annotation.Inject;
+import com.speedment.common.injector.annotation.WithState;
 
 /**
  *
@@ -28,7 +28,7 @@
 public final class StringIdentityMapper implements TypeMapper<String, String> {
 
     @ExecuteBefore(RESOLVED)
-    protected void install(@Inject(RESOLVED) TypeMapperComponent mappers) {
+    protected void install(@WithState(RESOLVED) TypeMapperComponent mappers) {
         mappers.install(String.class, String.class, this);
     }
 

common/injector/src/test/java/com/speedment/common/injector/test_b/A.java

@@ -16,7 +16,6 @@
  */
 package com.speedment.common.injector.test_b;
 
-import com.speedment.common.injector.State;
 import com.speedment.common.injector.annotation.Inject;
 
 /**
@@ -26,7 +25,7 @@
  */
 public final class A {
 
-    public @Inject(State.INITIALIZED) B b;
-    public @Inject(State.RESOLVED) C c;
+    public @Inject B b;
+    public @Inject C c;
 
 }

common/injector/src/test/java/com/speedment/common/injector/test_b/B.java

@@ -17,9 +17,9 @@
 package com.speedment.common.injector.test_b;
 
 import com.speedment.common.injector.State;
-import com.speedment.common.injector.annotation.Execute;
 import com.speedment.common.injector.annotation.ExecuteBefore;
 import com.speedment.common.injector.annotation.Inject;
+import com.speedment.common.injector.annotation.WithState;
 
 /**
  *
@@ -28,12 +28,9 @@
  */
 public final class B {
 
-    public @Inject(State.INITIALIZED) A a;
-    public @Inject(State.RESOLVED) C c;
-
-    @Execute
-    protected void anytime() {}
-
+    public @Inject A a;
+    public @Inject C c;
+
     @ExecuteBefore(State.RESOLVED)
-    protected void beforeResolve() {}
+    protected void beforeResolve(@WithState(State.INITIALIZED) A a, @WithState(State.RESOLVED) C c) {}
 }

common/injector/src/test/java/com/speedment/common/injector/test_b/C.java

@@ -16,7 +16,6 @@
  */
 package com.speedment.common.injector.test_b;
 
-import com.speedment.common.injector.State;
 import com.speedment.common.injector.annotation.Inject;
 
 /**
@@ -26,7 +25,7 @@
  */
 public final class C {
 
-    public @Inject(State.INITIALIZED) A a;
-    public @Inject(State.RESOLVED) B b;
+    public @Inject A a;
+    public @Inject B b;
 
 }