Add generic database interface in UC1 to support different storage types

Fix #343 (closed)

theodolite-benchmarks/uc1-beam/src/main/java/application/ConverterAdapter.java

+package application;
+
+import org.apache.beam.sdk.transforms.SimpleFunction;
+import org.apache.beam.sdk.values.TypeDescriptor;
+import rocks.theodolite.benchmarks.uc1.commons.RecordConverter;
+import titan.ccp.model.records.ActivePowerRecord;
+
+/**
+ * {@link SimpleFunction} which wraps a {@link RecordConverter} to be used with Beam.
+ * 
+ * @param <T> type the {@link RecordConverter} is associated with.
+ */
+public class ConverterAdapter<T> extends SimpleFunction<ActivePowerRecord, T> {
+
+  private static final long serialVersionUID = -5263671231838353747L; // NOPMD
+
+  private final RecordConverter<T> recordConverter;
+  private final TypeDescriptor<T> type;
+
+  /**
+   * Create a new {@link ConverterAdapter} with a given {@link RecordConverter} and the associated
+   * type.
+   */
+  public ConverterAdapter(final RecordConverter<T> recordConverter, final Class<T> type) {
+    super();
+    this.recordConverter = recordConverter;
+    this.type = TypeDescriptor.of(type);
+  }
+
+  @Override
+  public T apply(final ActivePowerRecord record) {
+    return this.recordConverter.convert(record);
+  }
+
+  @Override
+  public TypeDescriptor<T> getOutputTypeDescriptor() {
+    return this.type;
+  }
+
+}