Fix code quality issues

theodolite-benchmarks/uc2-application-flink/src/main/java/theodolite/uc2/application/StatsProcessWindowFunction.java

@@ -6,6 +6,10 @@ import org.apache.flink.streaming.api.functions.windowing.ProcessWindowFunction;
 import org.apache.flink.streaming.api.windowing.windows.TimeWindow;
 import org.apache.flink.util.Collector;
 
+/**
+ * A {@link ProcessWindowFunction} that forwards a computed {@link Stats} object along with its
+ * associated key.
+ */
 public class StatsProcessWindowFunction
     extends ProcessWindowFunction<Stats, Tuple2<String, Stats>, String, TimeWindow> {
 

theodolite-benchmarks/uc3-application-flink/src/main/java/theodolite/uc3/application/HourOfDayProcessWindowFunction.java

@@ -7,6 +7,10 @@ import org.apache.flink.streaming.api.windowing.windows.TimeWindow;
 import org.apache.flink.util.Collector;
 import theodolite.uc3.application.util.HourOfDayKey;
 
+/**
+ * A {@link ProcessWindowFunction} that forwards a computed {@link Stats} object along with its
+ * associated key.
+ */
 public class HourOfDayProcessWindowFunction
     extends ProcessWindowFunction<Stats, Tuple2<HourOfDayKey, Stats>, HourOfDayKey, TimeWindow> {
 

theodolite-benchmarks/uc3-application-flink/src/main/java/theodolite/uc3/application/util/HourOfDayKey.java

@@ -47,6 +47,10 @@ public class HourOfDayKey {
     return this.hourOfDay == k.hourOfDay && this.sensorId.equals(k.sensorId);
   }
 
+  /**
+   * Convert this {@link HourOfDayKey} into a byte array. This method is the inverse to
+   * {@code HourOfDayKey#fromByteArray()}.
+   */
   public byte[] toByteArray() {
     final int numBytes = (2 * Integer.SIZE + this.sensorId.length() * Character.SIZE) / Byte.SIZE;
     final ByteBuffer buffer = ByteBuffer.allocate(numBytes).order(ByteOrder.LITTLE_ENDIAN);
@@ -58,6 +62,10 @@ public class HourOfDayKey {
     return buffer.array();
   }
 
+  /**
+   * Construct a new {@link HourOfDayKey} from a byte array. This method is the inverse to
+   * {@code HourOfDayKey#toByteArray()}.
+   */
   public static HourOfDayKey fromByteArray(final byte[] bytes) {
     final ByteBuffer buffer = ByteBuffer.wrap(bytes).order(ByteOrder.LITTLE_ENDIAN);
     final int hourOfDay = buffer.getInt();

theodolite-benchmarks/uc3-application-flink/src/main/java/theodolite/uc3/application/util/HourOfDayKeyFactory.java

@@ -8,6 +8,8 @@ import java.time.LocalDateTime;
  */
 public class HourOfDayKeyFactory implements StatsKeyFactory<HourOfDayKey>, Serializable {
 
+  private static final long serialVersionUID = 4357668496473645043L; // NOPMD
+
   @Override
   public HourOfDayKey createKey(final String sensorId, final LocalDateTime dateTime) {
     final int hourOfDay = dateTime.getHour();

theodolite-benchmarks/uc3-application-flink/src/main/java/theodolite/uc3/application/util/HourOfDayKeySerde.java

@@ -18,6 +18,8 @@ import titan.ccp.common.kafka.simpleserdes.WriteBuffer;
 public class HourOfDayKeySerde extends Serializer<HourOfDayKey>
     implements BufferSerde<HourOfDayKey>, Serializable {
 
+  private static final long serialVersionUID = 1262778284661945041L; // NOPMD
+
   @Override
   public void serialize(final WriteBuffer buffer, final HourOfDayKey data) {
     buffer.putInt(data.getHourOfDay());