Added StatMetricCollector class

src/main/java/nu/ltd/fp/se/SystemMetrics.java

@@ -16,9 +16,10 @@ public class SystemMetrics {
     MetricCollector loadAverageCollector = new LoadAverageCollector(unameCollector);
     MetricCollector timeCollector = new TimeCollector(loadAverageCollector);
     MetricCollector meminfoCollector = new MeminfoCollector(timeCollector);
+    MetricCollector statsCollector = new StatMetricCollector(meminfoCollector);
 
     // this.metricCollector should be set to the last one
-    this.metricCollector = meminfoCollector;
+    this.metricCollector = statsCollector;
   }
 
   public void pollCollectorChain() {

src/main/java/nu/ltd/fp/se/collector/StatMetricCollector.java

@@ -0,0 +1,80 @@
+package nu.ltd.fp.se.collector;
+
+import io.prometheus.client.Gauge;
+import nu.ltd.fp.se.Constant;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileReader;
+import java.util.HashMap;
+import java.util.Map;
+
+public class StatMetricCollector extends AbstractMetricCollector implements MetricCollector {
+  static final Gauge cpuGauge = Gauge.build()
+    .name(Constant.EXPORTER_NAMESPACE + "cpu")
+    .help("Seconds the cpus spent in each mode.")
+    .labelNames("cpu","mode")
+    .register();
+
+  private HashMap<String, HashMap<String, Double>> cpuStat;
+
+
+  public StatMetricCollector() {
+    this.cpuStat = new HashMap<String, HashMap<String, Double>>();
+  }
+
+  public StatMetricCollector(MetricCollector nextCollector) {
+    this();
+    this.setNextCollector(nextCollector);
+  }
+
+  private void pollStats() {
+    File meminfoFile = new File(Constant.LXPROC_PATH + "/stat");
+    BufferedReader reader = null;
+
+    try {
+      reader = new BufferedReader(new FileReader(meminfoFile));
+      String line = null;
+      int i = 0;
+      // Skip the 1st line in the stat file
+      while ((line = reader.readLine()) != null) {
+        if (i > 0) {
+          String[] tokens = line.split("\\s+");
+          if (tokens[0].matches("^cpu\\d+")) {
+            HashMap<String, Double> statsInfo = cpuStat.get(tokens[0]);
+            if (statsInfo == null) { statsInfo = new HashMap<String, Double>(); }
+            statsInfo.put("user", Double.parseDouble(tokens[1])/100.0);
+            statsInfo.put("nice", Double.parseDouble(tokens[2])/100.0);
+            statsInfo.put("system", Double.parseDouble(tokens[3])/100.0);
+            statsInfo.put("idle", Double.parseDouble(tokens[4])/100.0);
+            statsInfo.put("iowait", Double.parseDouble(tokens[5])/100.0);
+            statsInfo.put("irq", Double.parseDouble(tokens[6])/100.0);
+            statsInfo.put("softirq", Double.parseDouble(tokens[7])/100.0);
+            cpuStat.put(tokens[0], statsInfo);
+          }
+        }
+        i++;
+      }
+    } catch (Exception e) {
+      System.out.println("got exception here.." + e.getMessage());
+    } finally {
+      try { if (reader != null) { reader.close(); } } catch (Exception e) {}
+    }
+  }
+
+  public void collectMetric() {
+    pollStats();
+    for (Map.Entry<String, HashMap<String, Double>> entry : cpuStat.entrySet()) {
+      String currentCpu = entry.getKey();
+      HashMap<String, Double> currentCpuStats = entry.getValue();
+      for (String stat : currentCpuStats.keySet()) {
+        cpuGauge.labels(currentCpu, stat).set(currentCpuStats.get(stat));
+      }
+    }
+
+    // Call next collector
+    if (this.getNextCollector() != null) {
+      this.getNextCollector().collectMetric();
+    }
+  }
+}