[PATCH] Do not put metadata on series if there are none (avoid NPE)

[Wald Commits]

# HG changeset patch
# User Tom Gottfried <tom at intevation.de>
# Date 1409232897 -7200
# Node ID fe67edde6189b6e68e4dbd2a5f8e296b71a2be2e
# Parent  969963ee61badbe0707850bf4094787c910bfa2b
Do not put metadata on series if there are none (avoid NPE).

diff -r 969963ee61ba -r fe67edde6189 artifacts/src/main/java/org/dive4elements/river/exports/process/BedWidthProcessor.java
--- a/artifacts/src/main/java/org/dive4elements/river/exports/process/BedWidthProcessor.java	Thu Aug 28 12:00:52 2014 +0200
+++ b/artifacts/src/main/java/org/dive4elements/river/exports/process/BedWidthProcessor.java	Thu Aug 28 15:34:57 2014 +0200
@@ -46,8 +46,10 @@
         Map<String, String> metaData = bundle.getFacet().getMetaData();
         StyledXYSeries series = new StyledXYSeries(bundle.getFacetDescription(),
                 theme);
-        series.putMetaData(metaData, bundle.getArtifact(), context);
-        yAxisLabel = metaData.get("Y");
+        if (!metaData.isEmpty()) {
+            series.putMetaData(metaData, bundle.getArtifact(), context);
+            yAxisLabel = metaData.get("Y");
+        }
         Object data = bundle.getData(context);
 
         if (data instanceof MorphologicWidth) {