Add @priority and make it the default (#73)

Author: rbygrave

inject-test/src/test/java/io/avaje/inject/SystemContextTest.java

@@ -1,6 +1,7 @@
 package io.avaje.inject;
 
 import org.example.coffee.fruit.Fruit;
+import org.example.coffee.list.A2Somei;
 import org.example.coffee.list.ASomei;
 import org.example.coffee.list.BSomei;
 import org.example.coffee.list.Somei;
@@ -16,28 +17,30 @@ public class SystemContextTest {
   @Test
   public void getBeansByPriority() {
 
-    final List<Somei> beans = SystemContext.getBeansByPriority(Somei.class);
-    assertThat(beans).hasSize(2);
+    final List<Somei> beans = SystemContext.context().getBeansByPriority(Somei.class, Priority.class);
+    assertThat(beans).hasSize(3);
 
     assertThat(beans.get(0)).isInstanceOf(BSomei.class);
     assertThat(beans.get(1)).isInstanceOf(ASomei.class);
+    assertThat(beans.get(2)).isInstanceOf(A2Somei.class);
   }
 
   @Test
   public void getBeansByPriority_withAnnotation() {
 
     final List<Somei> beans = SystemContext.context().getBeansByPriority(Somei.class, Priority.class);
-    assertThat(beans).hasSize(2);
+    assertThat(beans).hasSize(3);
 
     assertThat(beans.get(0)).isInstanceOf(BSomei.class);
     assertThat(beans.get(1)).isInstanceOf(ASomei.class);
+    assertThat(beans.get(2)).isInstanceOf(A2Somei.class);
   }
 
   @Test
   public void getBeansUnsorted_withPriority() {
 
     final List<Somei> beans = SystemContext.getBeans(Somei.class);
-    assertThat(beans).hasSize(2);
+    assertThat(beans).hasSize(3);
     // can't assert bean order
   }
 

inject-test/src/test/java/org/example/coffee/list/A2Somei.java

@@ -0,0 +1,14 @@
+package org.example.coffee.list;
+
+import javax.annotation.Priority;
+import javax.inject.Singleton;
+
+@Singleton
+@Priority(22)
+public class A2Somei implements Somei {
+
+  @Override
+  public String some() {
+    return "a";
+  }
+}

inject-test/src/test/java/org/example/coffee/priority/base/ABasei.java

@@ -0,0 +1,15 @@
+package org.example.coffee.priority.base;
+
+import io.avaje.inject.Priority;
+
+import javax.inject.Singleton;
+
+@Singleton
+@Priority(42)
+public class ABasei implements BaseIface {
+
+  @Override
+  public String other() {
+    return "a";
+  }
+}

inject-test/src/test/java/org/example/coffee/priority/base/BBasei.java

@@ -0,0 +1,15 @@
+package org.example.coffee.priority.base;
+
+import io.avaje.inject.Priority;
+
+import javax.inject.Singleton;
+
+@Singleton
+@Priority(7)
+public class BBasei implements BaseIface {
+
+  @Override
+  public String other() {
+    return "b";
+  }
+}

inject-test/src/test/java/org/example/coffee/priority/base/BaseIface.java

@@ -0,0 +1,6 @@
+package org.example.coffee.priority.base;
+
+public interface BaseIface {
+
+  String other();
+}

inject-test/src/test/java/org/example/coffee/priority/base/CBasei.java

@@ -0,0 +1,15 @@
+package org.example.coffee.priority.base;
+
+import io.avaje.inject.Priority;
+
+import javax.inject.Singleton;
+
+@Singleton
+@Priority(1)
+public class CBasei implements BaseIface {
+
+  @Override
+  public String other() {
+    return "a";
+  }
+}

inject-test/src/test/java/org/example/coffee/priority/base/PriorityTest.java

@@ -0,0 +1,36 @@
+package org.example.coffee.priority.base;
+
+import io.avaje.inject.BeanContext;
+import io.avaje.inject.SystemContext;
+import org.junit.jupiter.api.Test;
+
+import java.util.List;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class PriorityTest {
+
+  @Test
+  void getBeansByPriority() {
+    final BeanContext context = SystemContext.context();
+
+    final List<BaseIface> beans = context.getBeansByPriority(BaseIface.class);
+    assertExpectedOrder(beans);
+  }
+
+  @Test
+  void sortByPriority() {
+    final BeanContext context = SystemContext.context();
+
+    final List<BaseIface> beans = context.getBeans(BaseIface.class);
+    final List<BaseIface> sorted = context.sortByPriority(beans);
+
+    assertExpectedOrder(sorted);
+  }
+
+  private void assertExpectedOrder(List<BaseIface> sorted) {
+    assertThat(sorted.get(0)).isInstanceOf(CBasei.class);
+    assertThat(sorted.get(1)).isInstanceOf(BBasei.class);
+    assertThat(sorted.get(2)).isInstanceOf(ABasei.class);
+  }
+}

inject-test/src/test/java/org/example/coffee/priority/AOtheri.java renamed to inject-test/src/test/java/org/example/coffee/priority/custom/AOtheri.java

@@ -1,4 +1,4 @@
-package org.example.coffee.priority;
+package org.example.coffee.priority.custom;
 
 import javax.inject.Singleton;
 

inject-test/src/test/java/org/example/coffee/priority/BOtheri.java renamed to inject-test/src/test/java/org/example/coffee/priority/custom/BOtheri.java

@@ -1,4 +1,4 @@
-package org.example.coffee.priority;
+package org.example.coffee.priority.custom;
 
 import javax.inject.Singleton;
 

inject-test/src/test/java/org/example/coffee/priority/COtheri.java renamed to inject-test/src/test/java/org/example/coffee/priority/custom/COtheri.java

@@ -1,4 +1,4 @@
-package org.example.coffee.priority;
+package org.example.coffee.priority.custom;
 
 import javax.inject.Singleton;
 

inject-test/src/test/java/org/example/coffee/priority/CustomPriority.java renamed to inject-test/src/test/java/org/example/coffee/priority/custom/CustomPriority.java

@@ -1,4 +1,4 @@
-package org.example.coffee.priority;
+package org.example.coffee.priority.custom;
 
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;

inject-test/src/test/java/org/example/coffee/priority/CustomPriorityTest.java renamed to inject-test/src/test/java/org/example/coffee/priority/custom/CustomPriorityTest.java

@@ -1,4 +1,4 @@
-package org.example.coffee.priority;
+package org.example.coffee.priority.custom;
 
 import io.avaje.inject.BeanContext;
 import io.avaje.inject.SystemContext;
@@ -19,7 +19,7 @@ void test() {
 
     assertThat(sorted.get(0)).isInstanceOf(COtheri.class);
     assertThat(sorted.get(1)).isInstanceOf(BOtheri.class);
-    assertThat(sorted.get(1)).isInstanceOf(AOtheri.class);
+    assertThat(sorted.get(2)).isInstanceOf(AOtheri.class);
 
   }
 }

inject-test/src/test/java/org/example/coffee/priority/OtherIface.java renamed to inject-test/src/test/java/org/example/coffee/priority/custom/OtherIface.java

@@ -1,4 +1,4 @@
-package org.example.coffee.priority;
+package org.example.coffee.priority.custom;
 
 public interface OtherIface {
 

inject/src/main/java/io/avaje/inject/Priority.java

@@ -0,0 +1,28 @@
+package io.avaje.inject;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.Retention;
+import java.lang.annotation.Target;
+import java.util.List;
+
+import static java.lang.annotation.ElementType.TYPE;
+import static java.lang.annotation.RetentionPolicy.RUNTIME;
+
+/**
+ * The <code>Priority</code> annotation can be applied to classes to indicate
+ * in what order they should be returned via @{@link SystemContext#getBeansByPriority(Class)}.
+ * <p>
+ * Beans can be returned using other Priority annotation such as <code>javax.annotation.Priority</code>
+ * or any custom priority annotation that has an <code>int value()</code> attribute.
+ * </p>
+ *
+ * @see BeanContext#getBeansByPriority(Class)
+ * @see BeanContext#getBeansByPriority(Class, Class)
+ * @see BeanContext#sortByPriority(List, Class)
+ */
+@Documented
+@Retention(RUNTIME)
+@Target(TYPE)
+public @interface Priority {
+  int value();
+}

inject/src/main/java/io/avaje/inject/spi/DBeanContext.java

@@ -2,6 +2,7 @@
 
 import io.avaje.inject.BeanContext;
 import io.avaje.inject.BeanEntry;
+import io.avaje.inject.Priority;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -89,7 +90,7 @@ public <T> List<T> getBeans(Class<T> interfaceType) {
 
   @Override
   public <T> List<T> getBeansByPriority(Class<T> interfaceType) {
-    return getBeansByPriority(interfaceType, priorityAnnotation());
+    return getBeansByPriority(interfaceType, Priority.class);
   }
 
   @Override
@@ -100,7 +101,7 @@ public <T> List<T> getBeansByPriority(Class<T> interfaceType, Class<? extends An
 
   @Override
   public <T> List<T> sortByPriority(List<T> list) {
-    return sortByPriority(list, priorityAnnotation());
+    return sortByPriority(list, Priority.class);
   }
 
   @Override
@@ -131,18 +132,6 @@ public <T> List<T> sortByPriority(List<T> list, final Class<? extends Annotation
     return sorted;
   }
 
-  /**
-   * Return the optional <code>javax.annotation.Priority</code> annotation class or null.
-   */
-  @SuppressWarnings("unchecked")
-  private Class<? extends Annotation> priorityAnnotation() {
-    try {
-      return (Class<? extends Annotation>) Class.forName("javax.annotation.Priority");
-    } catch (ClassNotFoundException e) {
-      return null;
-    }
-  }
-
   @Override
   public List<Object> getBeansWithAnnotation(Class<?> annotation) {