Merge pull request #46 from adammelliott/inject-fields-during-before-…

…initialization

Fix metric injection into AOP-advised beans

pom.xml

@@ -146,6 +146,12 @@
 			<version>${spring.version}</version>
 			<scope>test</scope>
 		</dependency>
+		<dependency>
+			<groupId>org.aspectj</groupId>
+			<artifactId>aspectjweaver</artifactId>
+			<version>1.7.2</version>
+			<scope>test</scope>
+		</dependency>
 		<dependency>
 			<groupId>ch.qos.logback</groupId>
 			<artifactId>logback-classic</artifactId>

src/main/java/com/ryantenney/metrics/spring/InjectMetricAnnotationBeanPostProcessor.java

@@ -46,12 +46,7 @@ public InjectMetricAnnotationBeanPostProcessor(final MetricRegistry metrics) {
 	}
 
 	@Override
-	public Object postProcessBeforeInitialization(Object bean, String beanName) {
-		return bean;
-	}
-
-	@Override
-	public Object postProcessAfterInitialization(final Object bean, String beanName) {
+	public Object postProcessBeforeInitialization(final Object bean, String beanName) {
 		final Class<?> targetClass = AopUtils.getTargetClass(bean);
 
 		ReflectionUtils.doWithFields(targetClass, new FieldCallback() {
@@ -88,6 +83,11 @@ else if (Histogram.class == type) {
 		return bean;
 	}
 
+	@Override
+	public Object postProcessAfterInitialization(Object bean, String beanName) {
+		return bean;
+	}
+
 	@Override
 	public int getOrder() {
 		return LOWEST_PRECEDENCE - 2;

src/test/java/com/ryantenney/metrics/spring/AopFieldInjectionInteractionTest.java

@@ -0,0 +1,79 @@
+/**
+ * Copyright (C) 2012 Ryan W Tenney ([email protected])
+ *
+ * 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.ryantenney.metrics.spring;
+
+import static org.hamcrest.Matchers.*;
+import static org.junit.Assert.assertThat;
+
+import org.aspectj.lang.ProceedingJoinPoint;
+import org.aspectj.lang.annotation.Around;
+import org.aspectj.lang.annotation.Aspect;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+import com.codahale.metrics.Counter;
+import com.codahale.metrics.MetricRegistry;
+import com.ryantenney.metrics.annotation.InjectMetric;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration("classpath:aop-field-injection-interaction.xml")
+public class AopFieldInjectionInteractionTest {
+
+	@Autowired private MetricRegistry metricRegistry;
+	@Autowired private TestAspectTarget target;
+
+	@Test
+	public void testFieldInjectionShouldNotCauseErrorWhenTargetIsAopProxy() throws Exception {
+		// verify that AOP interception is working
+		assertThat(target.targetMethod(), is(5));
+
+		assertThat(metricRegistry.getCounters(), hasKey("targetCounter"));
+		assertThat(metricRegistry.getCounters().get("targetCounter").getCount(), is(1L));
+	}
+
+}
+
+@Aspect
+class TestAspectWrapper {
+
+	@Around("execution(* com.ryantenney.metrics.spring.TestAspectTarget.targetMethod())")
+	public Object aroundMethod(ProceedingJoinPoint joinPoint) throws Throwable {
+		joinPoint.proceed();
+		return 5;
+	}
+
+}
+
+interface TestAspectTarget {
+
+	public int targetMethod();
+
+}
+
+class TestAspectTargetImpl implements TestAspectTarget {
+
+	@InjectMetric(name = "targetCounter", absolute = true) private Counter counter;
+
+	@Override
+	public int targetMethod() {
+		this.counter.inc();
+		return 3;
+	}
+
+}

src/test/java/com/ryantenney/metrics/spring/TestSuite.java

@@ -25,6 +25,7 @@
 @RunWith(Suite.class)
 // @formatter:off
 @SuiteClasses({
+		AopFieldInjectionInteractionTest.class,
 		CovariantReturnTypeTest.class,
 		EnableMetricsTest.class,
 		HealthCheckTest.class,

src/test/resources/aop-field-injection-interaction.xml

@@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+
+    Copyright (C) 2012 Ryan W Tenney ([email protected])
+
+    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.
+
+-->
+<beans xmlns="http://www.springframework.org/schema/beans"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xmlns:aop="http://www.springframework.org/schema/aop"
+    xmlns:metrics="http://www.ryantenney.com/schema/metrics"
+
+    xsi:schemaLocation="
+            http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
+            http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd
+            http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.2.xsd
+            http://www.ryantenney.com/schema/metrics http://www.ryantenney.com/schema/metrics/metrics-3.0.xsd">
+
+    <aop:aspectj-autoproxy />
+
+    <metrics:annotation-driven />
+
+    <bean class="com.ryantenney.metrics.spring.TestAspectWrapper" />
+    <bean class="com.ryantenney.metrics.spring.TestAspectTargetImpl" />
+
+</beans>