Added MeminfoCollector class

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

@@ -0,0 +1,109 @@
+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;
+
+public class MeminfoCollector extends AbstractMetricCollector implements MetricCollector {
+  static final Gauge meminfoMemTotalGauge = Gauge.build()
+    .name(Constant.EXPORTER_NAMESPACE + "memory_MemTotal").help("Memory information field MemTotal.").register();
+
+  static final Gauge meminfoMemFreeGauge = Gauge.build()
+    .name(Constant.EXPORTER_NAMESPACE + "memory_MemTotal").help("Memory information field MemFree.").register();
+
+  static final Gauge meminfoMemSharedGauge = Gauge.build()
+    .name(Constant.EXPORTER_NAMESPACE + "memory_MemTotal").help("Memory information field MemShared.").register();
+
+  static final Gauge meminfoBuffersGauge = Gauge.build()
+    .name(Constant.EXPORTER_NAMESPACE + "memory_MemTotal").help("Memory information field Buffers.").register();
+
+  static final Gauge meminfoCachedGauge = Gauge.build()
+    .name(Constant.EXPORTER_NAMESPACE + "memory_MemTotal").help("Memory information field Cached.").register();
+
+  static final Gauge meminfoSwapCachedGauge = Gauge.build()
+    .name(Constant.EXPORTER_NAMESPACE + "memory_MemTotal").help("Memory information field SwapCached.").register();
+
+  static final Gauge meminfoActiveGauge = Gauge.build()
+    .name(Constant.EXPORTER_NAMESPACE + "memory_MemTotal").help("Memory information field Active.").register();
+
+  static final Gauge meminfoInactiveGauge = Gauge.build()
+    .name(Constant.EXPORTER_NAMESPACE + "memory_MemTotal").help("Memory information field Inactive.").register();
+
+  static final Gauge meminfoHighTotalGauge = Gauge.build()
+    .name(Constant.EXPORTER_NAMESPACE + "memory_MemTotal").help("Memory information field HighTotal.").register();
+
+  static final Gauge meminfoHighFreeGauge = Gauge.build()
+    .name(Constant.EXPORTER_NAMESPACE + "memory_MemTotal").help("Memory information field HighFree.").register();
+
+  static final Gauge meminfoLowTotalGauge = Gauge.build()
+    .name(Constant.EXPORTER_NAMESPACE + "memory_MemTotal").help("Memory information field LowTotal.").register();
+
+  static final Gauge meminfoLowFreeGauge = Gauge.build()
+    .name(Constant.EXPORTER_NAMESPACE + "memory_MemTotal").help("Memory information field LowFree.").register();
+
+  static final Gauge meminfoSwapTotalGauge = Gauge.build()
+    .name(Constant.EXPORTER_NAMESPACE + "memory_MemTotal").help("Memory information field SwapTotal.").register();
+
+  static final Gauge meminfoSwapFreeGauge = Gauge.build()
+    .name(Constant.EXPORTER_NAMESPACE + "memory_MemTotal").help("Memory information field SwapFree.").register();
+
+  private HashMap<String, Double> memInfo;
+
+  public MeminfoCollector() {
+    this.memInfo = new HashMap<String, Double>();
+  }
+
+  public MeminfoCollector(MetricCollector nextCollector) {
+    this();
+    this.setNextCollector(nextCollector);
+  }
+
+  private void pollMemInfo() {
+    Double fieldValue = 0.0;
+    File meminfoFile = new File(Constant.LXPROC_PATH + "/meminfo");
+    BufferedReader reader = null;
+    try {
+      reader = new BufferedReader(new FileReader(meminfoFile));
+      String line = null;
+      int i = 0;
+      // Skip the 1st 3 lines in the meminfo file
+      while ((line = reader.readLine()) != null && i > 2) {
+        String[] tokens = line.split(" ");
+        String[] fieldNameTokens = tokens[0].split(":");
+        memInfo.put(fieldNameTokens[0], Double.parseDouble(tokens[1]) * 1024);
+        i++;
+      }
+    } catch (Exception e) {
+    } finally {
+      try { if (reader != null) { reader.close(); } } catch (Exception e) {}
+    }
+  }
+
+  public void collectMetric() {
+    pollMemInfo();
+
+    meminfoMemTotalGauge.set(memInfo.get("MemTotal"));
+    meminfoMemFreeGauge.set(memInfo.get("MemFree"));
+    meminfoMemSharedGauge.set(memInfo.get("MemShared"));
+    meminfoBuffersGauge.set(memInfo.get("Buffers"));
+    meminfoCachedGauge.set(memInfo.get("Cached"));
+    meminfoSwapCachedGauge.set(memInfo.get("SwapCached"));
+    meminfoActiveGauge.set(memInfo.get("Active"));
+    meminfoInactiveGauge.set(memInfo.get("Inactive"));
+    meminfoHighTotalGauge.set(memInfo.get("HighTotal"));
+    meminfoHighFreeGauge.set(memInfo.get("HighFree"));
+    meminfoLowTotalGauge.set(memInfo.get("LowTotal"));
+    meminfoLowFreeGauge.set(memInfo.get("LowFree"));
+    meminfoSwapTotalGauge.set(memInfo.get("SwapTotal"));
+    meminfoSwapFreeGauge.set(memInfo.get("SwapFree"));
+
+    // Call next collector
+    if (this.getNextCollector() != null) {
+      this.getNextCollector().collectMetric();
+    }
+  }
+}