Do not fail completely when re-registering metrics with the same name

pom.xml

@@ -462,5 +462,4 @@
 			</build>
 		</profile>
 	</profiles>
-
 </project>

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

@@ -0,0 +1,28 @@
+package com.ryantenney.metrics.spring;
+
+import java.util.regex.Pattern;
+
+import com.codahale.metrics.Metric;
+import com.codahale.metrics.MetricFilter;
+
+public class RegexMetricFilter implements MetricFilter {
+    private final Pattern filter;
+
+    public RegexMetricFilter(String pattern) {
+        this(Pattern.compile(pattern));
+    }
+
+    private RegexMetricFilter(Pattern filter) {
+        this.filter = filter;
+    }
+
+    @Override
+    public boolean matches(String name, Metric metric) {
+        return filter.matcher(name).matches();
+    }
+
+    @Override
+    public String toString() {
+        return "[MetricFilter regex=" + filter.pattern() + "]";
+    }
+}

src/main/java/com/ryantenney/metrics/spring/config/RegisterMetricBeanDefinitionParser.java

@@ -15,8 +15,12 @@
  */
 package com.ryantenney.metrics.spring.config;
 
+import static com.ryantenney.metrics.spring.config.MetricsNamespaceHandler.METRICS_NAMESPACE;
+
 import java.util.List;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.InitializingBean;
 import org.springframework.beans.factory.config.BeanDefinition;
 import org.springframework.beans.factory.config.ConstructorArgumentValues;
@@ -31,10 +35,10 @@
 import org.w3c.dom.Element;
 
 import com.codahale.metrics.Metric;
+import com.codahale.metrics.MetricFilter;
 import com.codahale.metrics.MetricRegistry;
 import com.codahale.metrics.MetricSet;
-
-import static com.ryantenney.metrics.spring.config.MetricsNamespaceHandler.METRICS_NAMESPACE;
+import com.ryantenney.metrics.spring.RegexMetricFilter;
 
 class RegisterMetricBeanDefinitionParser implements BeanDefinitionParser {
 
@@ -79,6 +83,7 @@ public BeanDefinition parse(Element element, ParserContext parserContext) {
 
 	public static class MetricRegisterer implements InitializingBean {
 
+	    private final Logger log = LoggerFactory.getLogger(MetricRegisterer.class);
 		private final MetricRegistry metricRegistry;
 		private final String name;
 		private final Metric metric;
@@ -95,9 +100,22 @@ public MetricRegisterer(MetricRegistry metricRegistry, String name, Metric metri
 
 		@Override
 		public void afterPropertiesSet() throws Exception {
-			metricRegistry.register(name, metric);
+		    try {
+		        metricRegistry.register(name, metric);
+		    } catch (IllegalArgumentException iae) {
+		        // handle duplicate names gracefully
+		        replaceMetrics();
+		    }
 		}
 
+        private void replaceMetrics() {
+            // Metrics really should provide a way to do this themselves
+            log.warn("Possible duplicate registry detected for name '{}', replacing with {}", name, metric.getClass());
+            MetricFilter filter = new RegexMetricFilter("^" + name + ".*$");
+            metricRegistry.removeMatching(filter);
+            metricRegistry.register(name, metric);
+        }
 	}
 
 }
+

src/main/java/com/ryantenney/metrics/spring/reporter/AbstractReporterFactoryBean.java

@@ -16,7 +16,6 @@
 package com.ryantenney.metrics.spring.reporter;
 
 import java.util.Map;
-import java.util.regex.Pattern;
 
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.BeanFactoryAware;
@@ -27,13 +26,15 @@
 import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.core.convert.support.DefaultConversionService;
 
-import com.codahale.metrics.Metric;
 import com.codahale.metrics.MetricFilter;
 import com.codahale.metrics.MetricRegistry;
+import com.ryantenney.metrics.spring.RegexMetricFilter;
 
 public abstract class AbstractReporterFactoryBean<T> implements FactoryBean<T>, InitializingBean, BeanFactoryAware {
 
-	protected static final String FILTER_PATTERN = "filter";
+
+
+    protected static final String FILTER_PATTERN = "filter";
 	protected static final String FILTER_REF = "filter-ref";
 
 	private MetricRegistry metricRegistry;
@@ -155,20 +156,7 @@ else if (hasProperty(FILTER_REF)) {
 	}
 
 	protected MetricFilter metricFilterPattern(String pattern) {
-		final Pattern filter = Pattern.compile(pattern);
-		return new MetricFilter() {
-
-			@Override
-			public boolean matches(String name, Metric metric) {
-				return filter.matcher(name).matches();
-			}
-
-			@Override
-			public String toString() {
-				return "[MetricFilter regex=" + filter.pattern() + "]";
-			}
-
-		};
+		return new RegexMetricFilter(pattern);
 	}
 
 }

src/test/resources/register-element-test.xml

@@ -35,5 +35,11 @@
 		<bean metrics:name="jvm.thread-states" class="com.codahale.metrics.jvm.ThreadStatesGaugeSet" />
 		<bean metrics:name="jvm.fd.usage" class="com.codahale.metrics.jvm.FileDescriptorRatioGauge" />
 	</metrics:register>
+    <!--  test duplicate names due to spring lifecycle issues this can occur -->
+    <metrics:register metric-registry="metrics">
+        <bean metrics:name="jvm.gc" class="com.codahale.metrics.jvm.GarbageCollectorMetricSet" />
+        <bean metrics:name="jvm.fd.usage" class="com.codahale.metrics.jvm.FileDescriptorRatioGauge" />
+    </metrics:register>
+
 
 </beans>