#12 - Add RequestTimingListener ... for per request timing callback

Author: rbygrave

src/main/java/org/avaje/metric/report/BaseRequestTimingReporter.java

@@ -0,0 +1,44 @@
+package org.avaje.metric.report;
+
+import org.avaje.metric.RequestTiming;
+
+import java.util.Collections;
+import java.util.List;
+
+/**
+ * Combines a RequestTimingReporter with a list of RequestTimingListener.
+ */
+public class BaseRequestTimingReporter implements RequestTimingReporter {
+
+  final RequestTimingReporter reporter;
+
+  final List<RequestTimingListener> listeners;
+
+  public BaseRequestTimingReporter(RequestTimingReporter reporter, List<RequestTimingListener> listeners) {
+    this.reporter = reporter;
+    this.listeners = (listeners != null) ? listeners : Collections.EMPTY_LIST;
+  }
+
+  @Override
+  public void report(List<RequestTiming> requestTimings) {
+    if (reporter != null) {
+      reporter.report(requestTimings);
+    }
+    if (!listeners.isEmpty()) {
+      // notify all the listeners
+      for (int t = 0; t <requestTimings.size(); t++) {
+        RequestTiming requestTiming = requestTimings.get(t);
+        for (int l = 0; l < listeners.size(); l++) {
+          listeners.get(l).onRequestTiming(requestTiming);
+        }
+      }
+    }
+  }
+
+  @Override
+  public void cleanup() {
+    if (reporter != null) {
+      reporter.cleanup();
+    }
+  }
+}

src/main/java/org/avaje/metric/report/BasicRequestTimingWriter.java

@@ -51,7 +51,7 @@ public void write(Writer writer, List<RequestTiming> requestTimings) throws IOEx
   /**
    * Write the RequestTiming to the writer.
    */
-  protected void writeEntry(Writer writer, RequestTiming requestTiming) throws IOException {
+  public void writeEntry(Writer writer, RequestTiming requestTiming) throws IOException {
 
     // note that the entries are in reverse order
     List<RequestTimingEntry> entries = requestTiming.getEntries();
@@ -73,14 +73,14 @@ protected void writeEntry(Writer writer, RequestTiming requestTiming) throws IOE
   /**
    * Write the footer content to the writer.
    */
-  private void writeFooter(Writer writer) throws IOException {
+  protected void writeFooter(Writer writer) throws IOException {
     writer.write("\n");
   }
 
   /**
    * Write the header content to the writer.
    */
-  private void writeHeader(Writer writer, RequestTimingEntry headerEntry, RequestTiming requestTiming, long totalExeNanos) throws IOException {
+  protected void writeHeader(Writer writer, RequestTimingEntry headerEntry, RequestTiming requestTiming, long totalExeNanos) throws IOException {
 
     Date reportTime = new Date(requestTiming.getReportTime());
 
@@ -104,7 +104,7 @@ private void writeHeader(Writer writer, RequestTimingEntry headerEntry, RequestT
   /**
    * Write the detail entry to the writer.
    */
-  private void writeDetail(Writer writer, RequestTimingEntry entry, long totalExeNanos) throws IOException {
+  protected void writeDetail(Writer writer, RequestTimingEntry entry, long totalExeNanos) throws IOException {
 
     long executionNanos = entry.getExecutionNanos();
     long percentage = percentage(totalExeNanos, executionNanos);
@@ -134,7 +134,7 @@ private void writeDetail(Writer writer, RequestTimingEntry entry, long totalExeN
   /**
    * Write the value padding with spaces out to padToWidth.
    */
-  private void pad(Writer writer, int padToWidth, long value) throws IOException {
+  protected void pad(Writer writer, int padToWidth, long value) throws IOException {
     String s = String.valueOf(value);
     writer.write(s);
     for (int i=0; i<padToWidth-s.length(); i++) {
@@ -145,22 +145,22 @@ private void pad(Writer writer, int padToWidth, long value) throws IOException {
   /**
    * Return the percentage of execution time as a value from 0 to 100.
    */
-  private long percentage(long totalExeNanos, long executionNanos) {
+  protected long percentage(long totalExeNanos, long executionNanos) {
     return (100 * executionNanos) / totalExeNanos;
   }
 
 
   /**
    * Return the nanos as milliseconds.
    */
-  long toMillis(long nanos) {
+  protected long toMillis(long nanos) {
     return TimeUnit.NANOSECONDS.toMillis(nanos);
   }
 
   /**
    * Return the nanos as microseconds.
    */
-  long toMicros(long nanos) {
+  protected long toMicros(long nanos) {
     return TimeUnit.NANOSECONDS.toMicros(nanos);
   }
 }

src/main/java/org/avaje/metric/report/MetricReportConfig.java

@@ -1,5 +1,7 @@
 package org.avaje.metric.report;
 
+import java.util.ArrayList;
+import java.util.List;
 import java.util.concurrent.ScheduledExecutorService;
 
 /**
@@ -29,6 +31,8 @@ public class MetricReportConfig {
 
   ScheduledExecutorService executor;
 
+  List<RequestTimingListener> requestTimingListeners = new ArrayList<>();
+
   /**
    * Return the HeaderInfo which identifies this application instance.
    * <p/>
@@ -204,4 +208,25 @@ public RequestTimingReporter getRequestTimingReporter() {
   public void setRequestTimingReporter(RequestTimingReporter requestTimingReporter) {
     this.requestTimingReporter = requestTimingReporter;
   }
+
+  /**
+   * Add a RequestTimingListener.
+   */
+  public void addRequestTimingListener(RequestTimingListener listener) {
+    this.requestTimingListeners.add(listener);
+  }
+
+  /**
+   * Return the list of RequestTimingListener's.
+   */
+  public List<RequestTimingListener> getRequestTimingListeners() {
+    return requestTimingListeners;
+  }
+
+  /**
+   * Set the list of RequestTimingListener's.
+   */
+  public void setRequestTimingListeners(List<RequestTimingListener> requestTimingListeners) {
+    this.requestTimingListeners = requestTimingListeners;
+  }
 }

src/main/java/org/avaje/metric/report/MetricReportManager.java

@@ -89,7 +89,8 @@ protected RequestTimingReporter defaultReqReporter(MetricReportConfig config) {
       return config.getRequestTimingReporter();
     }
     // just use the default implementation based on config
-    return new RequestFileReporter(config);
+    RequestTimingReporter fileReporter = new RequestFileReporter(config);
+    return new BaseRequestTimingReporter(fileReporter, config.getRequestTimingListeners());
   }
 
   /**

src/main/java/org/avaje/metric/report/RequestTimingListener.java

@@ -0,0 +1,15 @@
+package org.avaje.metric.report;
+
+import org.avaje.metric.RequestTiming;
+
+/**
+ * Listener that can be notified when a RequestTiming is reported.
+ */
+public interface RequestTimingListener {
+
+  /**
+   * Listener notified for each RequestTiming that has been reported.
+   */
+  void onRequestTiming(RequestTiming requestTiming);
+
+}