use inline data for bar charts

Bar charts only need very little data. There is no need to create
a file for two numbers.

pdb-plotting/src/main/java/org/lucares/pdb/plot/api/AggregateHandler.java

@@ -52,12 +52,15 @@ public abstract class AggregateHandler implements Appender {
 
     abstract AxisSettings createYAxisSettings(GnuplotSettings settings, Collection<DataSeries> dataSeries);
 
-    abstract void addPlot(StringBuilder result, CustomAggregator aggregator, LineStyle lineStyle,
+    abstract String addPlot(CustomAggregator aggregator, LineStyle lineStyle, Optional<String> title);
-            Optional<String> title);
 
     abstract CustomAggregator createCustomAggregator(Path tmpDir, PlotSettings plotSettings, long fromEpochMilli,
             long toEpochMilli);
 
+    String beforePlot(final CustomAggregator aggregator) {
+        return "";
+    }
+
     protected String gnuplotTitle(final Optional<String> title) {
 
         return title.isPresent() ? "title '" + title.get() + "'" : "notitle";

pdb-plotting/src/main/java/org/lucares/pdb/plot/api/AggregateHandlerCollection.java

@@ -95,6 +95,9 @@ public class AggregateHandlerCollection {
 
     public void addPlots(final StringBuilder result, final Collection<DataSeries> dataSeries) {
 
+        final StringBuilder plots = new StringBuilder();
+        final StringBuilder beforePlots = new StringBuilder();
+
         boolean first = true;
         final List<AggregateHandler> handlersInPlottingOrder = CollectionUtils.copySort(aggregateHandlers,
                 PLOTTING_ORDER);
@@ -113,11 +116,20 @@ public class AggregateHandlerCollection {
                         index++;
                     }
 
-                    handler.addPlot(result, aggregator, dataSerie.getStyle(), title);
+                    final String beforePlot = handler.beforePlot(aggregator);
+                    beforePlots.append(beforePlot);
+
+                    final String plot = handler.addPlot(aggregator, dataSerie.getStyle(), title);
+                    plots.append(plot);
                 }
             }
 
             first = false;
         }
+
+        result.append(beforePlots);
+        result.append("\n");
+        result.append("plot ");
+        result.append(plots);
     }
 }

pdb-plotting/src/main/java/org/lucares/pdb/plot/api/Appender.java

@@ -15,4 +15,8 @@ public interface Appender {
         builder.append(String.format(Locale.US, format, args));
     }
 
+    default String formatln(final String format, final Object... args) {
+        return String.format(Locale.US, format + "\n", args);
+    }
+
 }

pdb-plotting/src/main/java/org/lucares/pdb/plot/api/BarChartAggregator.java

@@ -5,6 +5,7 @@ import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.util.UUID;
 
 import org.lucares.pdb.api.RuntimeIOException;
 
@@ -16,6 +17,8 @@ public class BarChartAggregator implements CustomAggregator, IndexedAggregator {
 
     private Long index = null;
 
+    private final String dataName = "$data" + UUID.randomUUID().toString().replace("-", "");
+
     public BarChartAggregator(final Path tmpDir) {
         super();
         this.tmpDir = tmpDir;
@@ -39,11 +42,7 @@ public class BarChartAggregator implements CustomAggregator, IndexedAggregator {
         count++;
     }
 
-    @Override
+    public String asCsv() {
-    public AggregatedData getAggregatedData() {
-        try {
-            final File dataFile = File.createTempFile("bar", ".dat", tmpDir.toFile());
-
         final StringBuilder csv = new StringBuilder();
 
         csv.append(index + 0.5);
@@ -51,9 +50,17 @@ public class BarChartAggregator implements CustomAggregator, IndexedAggregator {
         csv.append("");
         csv.append(",");
         csv.append(count);
-            csv.append("\n");
+        return csv.toString();
+    }
 
-            Files.writeString(dataFile.toPath(), csv.toString(), StandardCharsets.UTF_8);
+    @Override
+    public AggregatedData getAggregatedData() {
+        try {
+            final File dataFile = File.createTempFile("bar", ".dat", tmpDir.toFile());
+
+            final String csv = asCsv();
+
+            Files.writeString(dataFile.toPath(), csv, StandardCharsets.UTF_8);
             final AggregatedData result = new AggregatedData("label", dataFile);
             return result;
         } catch (final IOException e) {
@@ -66,4 +73,9 @@ public class BarChartAggregator implements CustomAggregator, IndexedAggregator {
         return Aggregate.BAR;
     }
 
+    public String getDataName() {
+
+        return dataName;
+    }
+
 }

pdb-plotting/src/main/java/org/lucares/pdb/plot/api/BarChartHandler.java

@@ -68,19 +68,29 @@ public class BarChartHandler extends AggregateHandler {
     }
 
     @Override
-    void addPlot(final StringBuilder result, final CustomAggregator aggregator, final LineStyle lineStyle,
+    String beforePlot(final CustomAggregator aggregator) {
-            final Optional<String> title) {
+        final StringBuilder result = new StringBuilder();
 
-        final AggregatedData aggregatedData = aggregator.getAggregatedData();
+        final BarChartAggregator barAggregator = (BarChartAggregator) aggregator;
 
+        appendfln(result, "%s <<EOD", barAggregator.getDataName());
+        appendln(result, barAggregator.asCsv());
+        appendln(result, "EOD");
+        return result.toString();
+    }
+
+    @Override
+    String addPlot(final CustomAggregator aggregator, final LineStyle lineStyle, final Optional<String> title) {
+
+        final BarChartAggregator barAggregator = (BarChartAggregator) aggregator;
         /*
          * appendfln(result,
          * "'%s' using 1:3:xtic(2) notitle with %s axes %s fs solid %s, \\", //
          * aggregatedData.getDataFile(), // GnuplotLineType.Bar, // gnuplotXYAxis(), //
          * lineStyle// );
          */
-        appendfln(result, "'%s' using 1:3:xtic(2) %s with %s axes %s fs solid %s, \\", //
+        return formatln("'%s' using 1:3:xtic(2) %s with %s axes %s fs solid %s, \\", //
-                aggregatedData.getDataFile(), //
+                barAggregator.getDataName(), //
                 gnuplotTitle(title), //
                 GnuplotLineType.Bar, //
                 gnuplotXYAxis(), //

pdb-plotting/src/main/java/org/lucares/pdb/plot/api/CumulativeDistributionHandler.java

@@ -69,12 +69,11 @@ public class CumulativeDistributionHandler extends AggregateHandler {
     }
 
     @Override
-    public void addPlot(final StringBuilder result, final CustomAggregator aggregator, final LineStyle lineStyle,
+    public String addPlot(final CustomAggregator aggregator, final LineStyle lineStyle, final Optional<String> title) {
-            final Optional<String> title) {
 
         final AggregatedData aggregatedData = aggregator.getAggregatedData();
 
-        appendfln(result, "'%s' using 1:2 %s with lines axes %s lw 2 %s, \\", //
+        return formatln("'%s' using 1:2 %s with lines axes %s lw 2 %s, \\", //
                 aggregatedData.getDataFile().getAbsolutePath(), //
                 gnuplotTitle(title), //
                 gnuplotXYAxis(), //

pdb-plotting/src/main/java/org/lucares/pdb/plot/api/HistogramHandler.java

@@ -54,11 +54,10 @@ public class HistogramHandler extends AggregateHandler {
     }
 
     @Override
-    void addPlot(final StringBuilder result, final CustomAggregator aggregator, final LineStyle lineStyle,
+    String addPlot(final CustomAggregator aggregator, final LineStyle lineStyle, final Optional<String> title) {
-            final Optional<String> title) {
         final AggregatedData aggregatedData = aggregator.getAggregatedData();
 
-        appendfln(result, "'%s' using 1:2 %s with boxes axes %s lw 1 %s, \\", //
+        return formatln("'%s' using 1:2 %s with boxes axes %s lw 1 %s, \\", //
                 aggregatedData.getDataFile().getAbsolutePath(), //
                 gnuplotTitle(title), //
                 gnuplotXYAxis(), //

pdb-plotting/src/main/java/org/lucares/pdb/plot/api/ParallelRequestsAggregate.java

@@ -48,10 +48,9 @@ public class ParallelRequestsAggregate extends AggregateHandler {
     }
 
     @Override
-    public void addPlot(final StringBuilder result, final CustomAggregator aggregator, final LineStyle lineStyle,
+    public String addPlot(final CustomAggregator aggregator, final LineStyle lineStyle, final Optional<String> title) {
-            final Optional<String> title) {
         final AggregatedData aggregatedData = aggregator.getAggregatedData();
-        appendfln(result, "'%s' using 1:2 %s with filledcurve axes %s lw 1 %s, \\", //
+        return formatln("'%s' using 1:2 %s with filledcurve axes %s lw 1 %s, \\", //
                 aggregatedData.getDataFile().getAbsolutePath(), //
                 gnuplotTitle(title), //
                 gnuplotXYAxis(), //

pdb-plotting/src/main/java/org/lucares/pdb/plot/api/ScatterAggregateHandler.java

@@ -44,11 +44,10 @@ public class ScatterAggregateHandler extends AggregateHandler {
     }
 
     @Override
-    public void addPlot(final StringBuilder result, final CustomAggregator aggregator, final LineStyle lineStyle,
+    public String addPlot(final CustomAggregator aggregator, final LineStyle lineStyle, final Optional<String> title) {
-            final Optional<String> title) {
 
         final AggregatedData aggregatedData = aggregator.getAggregatedData();
-        appendfln(result, "'%s' using 1:2 %s with %s axes %s %s, \\", //
+        return formatln("'%s' using 1:2 %s with %s axes %s %s, \\", //
                 aggregatedData.getDataFile(), //
                 gnuplotTitle(title), //
                 GnuplotLineType.Points, //

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

@@ -67,8 +67,6 @@ public class GnuplotFileGenerator implements Appender {
         // appendfln(result, "set xrange [-1:1]");
         appendfln(result, "set boxwidth 0.5");
 
-        appendf(result, "plot ");
-
         settings.getAggregates().addPlots(result, dataSeries);
 
         // Add a plot outside of the visible range. Without this gnuplot would not