Fix bad 'this' reference in updateFromEventEmitter

Add an example of using jmxstat.jar

examples/graphjmx.ex.js

@@ -0,0 +1,47 @@
+/*jslint forin:true */
+
+var assert = require('assert'),
+    child_process = require('child_process'),
+    reporting = require('../lib/reporting'),
+    REPORT_MANAGER = reporting.REPORT_MANAGER;
+
+REPORT_MANAGER.setLogFile('.reporting.test-output.html');
+
+var hostAndPort = 'localhost:9999',
+    refreshInterval = 2;
+
+var report = REPORT_MANAGER.addReport('JMX'),
+    memory = report.getChart('Memory'),
+    cpu = report.getChart('CPU');
+
+var jmx = reporting.spawnAndMonitor(
+            /HeapMemoryUsage.max=(.*) HeapMemoryUsage.committed=(.*) HeapMemoryUsage.used=(.*) SystemLoadAverage=([0-9\.]*)/,
+            ['max', 'committed', 'used', 'loadavg'],
+            'java', [
+              '-jar', 'jmxstat/jmxstat.jar',
+              hostAndPort,
+              'java.lang:type=Memory[HeapMemoryUsage.max,HeapMemoryUsage.committed,HeapMemoryUsage.used]',
+              'java.lang:type=OperatingSystem[SystemLoadAverage]',
+              refreshInterval
+            ]
+          ),
+    iostat = reporting.spawnAndMonitor(
+            / +[^ ]+ +[^ ]+ +[^ ]+ +([^ ]+) +([^ ]+) +[^ ]+ +[^ ]+ +[^ ]+ +[^ ]+/,
+            ['user', 'system'],
+            'iostat', [refreshInterval]
+          );
+
+jmx.stderr.on('data', function (data) {
+  console.log(data.toString());
+});
+
+jmx.on('exit', function (code) {
+  if (code !== 0) { console.log('JMX monitor died with code ' + code); }
+  process.exit(code);
+});
+
+jmx.on('data', function(data) {
+  memory.put({max: data.max/1024, committed: data.committed/1024, used: data.used/1024});
+});
+
+cpu.updateFromEventEmitter(iostat, ['user', 'system']);

lib/reporting/report.js

@@ -113,13 +113,14 @@ Chart.prototype = {
       
     */
     updateFromEventEmitter: function(eventEmitter, fields, event) {
-      eventEmitter.on(event || 'data', function(data) { 
-        var row = {};
-        fields.forEach(function(i) {
-          if (data[i] !== undefined) { row[i] = data[i]; }
+        var self = this;
+        eventEmitter.on(event || 'data', function(data) {
+            var row = {};
+            fields.forEach(function(i) {
+                if (data[i] !== undefined) { row[i] = data[i]; }
+            });
+            self.put(row);
         });
-        this.put(row);
-      });
     }
 };