add dashboard

pdb-plotting/src/main/java/org/lucares/recommind/logs/PercentilePlot.java

@@ -101,7 +101,7 @@ public class PercentilePlot implements ConcretePlotter {
 			gnuplotSettings.setKeyOutside(plotSettings.isKeyOutside());
 			gnuplot.plot(gnuplotSettings, dataSeries);
 
-			return new PlotResult(outputFile, dataSeries);
+			return new PlotResult(outputFile, dataSeries, null); // TODO thumbail
 		} catch (final InterruptedException e) {
 			Thread.currentThread().interrupt();
 			throw new IllegalStateException("Plotting was interrupted.");

pdb-plotting/src/main/java/org/lucares/recommind/logs/PlotResult.java

@@ -6,11 +6,13 @@ import java.util.List;
 public class PlotResult {
 	private final Path imagePath;
 	private final List<DataSeries> dataSeries;
+	private final Path thumbnail;
 
-	public PlotResult(final Path imagePath, final List<DataSeries> dataSeries) {
+	public PlotResult(final Path imagePath, final List<DataSeries> dataSeries, final Path thumbnail) {
 		super();
 		this.imagePath = imagePath;
 		this.dataSeries = dataSeries;
+		this.thumbnail = thumbnail;
 	}
 
 	public Path getImageName() {
@@ -21,6 +23,14 @@ public class PlotResult {
 		return imagePath;
 	}
 
+	public Path getThumbnailName() {
+		return thumbnail.getFileName();
+	}
+
+	public Path getThumbnailPath() {
+		return thumbnail;
+	}
+
 	public List<DataSeries> getDataSeries() {
 		return dataSeries;
 	}

pdb-plotting/src/main/java/org/lucares/recommind/logs/ScatterPlot.java

@@ -1,5 +1,7 @@
 package org.lucares.recommind.logs;
 
+import java.awt.Graphics2D;
+import java.awt.image.BufferedImage;
 import java.io.BufferedWriter;
 import java.io.File;
 import java.io.FileOutputStream;
@@ -21,6 +23,8 @@ import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.stream.Stream;
 
+import javax.imageio.ImageIO;
+
 import org.lucares.pdb.api.Entry;
 import org.lucares.pdb.api.GroupResult;
 import org.lucares.pdb.api.Result;
@@ -118,7 +122,10 @@ public class ScatterPlot implements ConcretePlotter {
 			gnuplotSettings.setKeyOutside(plotSettings.isKeyOutside());
 			gnuplot.plot(gnuplotSettings, dataSeries);
 
-			return new PlotResult(outputFile, dataSeries);
+			final Path thumbnail = createOptionalThumbnail(outputFile, plotSettings.getThumbnailMaxWidth(),
+					plotSettings.getThumbnailMaxHeight());
+
+			return new PlotResult(outputFile, dataSeries, thumbnail);
 		} catch (final InterruptedException e) {
 			Thread.currentThread().interrupt();
 			throw new IllegalStateException("Plotting was interrupted.");
@@ -130,6 +137,44 @@ public class ScatterPlot implements ConcretePlotter {
 		}
 	}
 
+	private static BufferedImage resizeImage(final BufferedImage originalImage, final Integer img_width,
+			final Integer img_height) {
+		final int type = originalImage.getType() == 0 ? BufferedImage.TYPE_INT_ARGB : originalImage.getType();
+		final BufferedImage resizedImage = new BufferedImage(img_width, img_height, type);
+		final Graphics2D g = resizedImage.createGraphics();
+		g.drawImage(originalImage, 0, 0, img_width, img_height, null);
+		g.dispose();
+
+		return resizedImage;
+	}
+
+	private Path createOptionalThumbnail(final Path originalImage, final int thumbnailMaxWidth,
+			final int thumbnailMaxHeight) {
+
+		Path result;
+		if (thumbnailMaxWidth > 0 && thumbnailMaxHeight > 0) {
+			try {
+				final long start = System.nanoTime();
+				final BufferedImage image = ImageIO.read(originalImage.toFile());
+
+				final BufferedImage thumbnail = resizeImage(image, thumbnailMaxWidth, thumbnailMaxHeight);
+				final Path thumbnailPath = originalImage.getParent()
+						.resolve(originalImage.getFileName() + ".thumbnail.jpg");
+
+				ImageIO.write(thumbnail, "JPG", thumbnailPath.toFile());
+				LOGGER.info("thumbnail creation: " + (System.nanoTime() - start) / 1_000_000.0 + "ms");
+				result = thumbnailPath;
+			} catch (final IOException e) {
+				LOGGER.warn("failed to scale image", e);
+				result = null;
+			}
+		} else {
+			result = null;
+		}
+
+		return result;
+	}
+
 	private void defineXAxis(final GnuplotSettings gnuplotSettings, final OffsetDateTime minDate,
 			final OffsetDateTime maxDate) {