add some diagnostics in case of table error

gradle.properties

@@ -1,5 +1,5 @@
 group = org.xbib.graphics
 name = graphics
-version = 4.5.8
+version = 4.5.9
 
 org.gradle.warning.mode = ALL

graphics-pdfbox-layout/src/main/java/org/xbib/graphics/pdfbox/layout/table/AbstractCell.java

@@ -236,4 +236,9 @@ public abstract class AbstractCell implements Cell {
     }
 
     protected abstract Renderer createDefaultRenderer();
+
+    @Override
+    public String toString() {
+        return "AbstractCell";
+    }
 }

graphics-pdfbox-layout/src/main/java/org/xbib/graphics/pdfbox/layout/table/Column.java

@@ -8,7 +8,7 @@ public class Column {
 
     private float width;
 
-    Column(final float width) {
+    Column(float width) {
         if (width < 0) {
             throw new IllegalArgumentException("Column width must be non-negative");
         }
@@ -42,4 +42,9 @@ public class Column {
     public Column getNext() {
         return next;
     }
+
+    @Override
+    public String toString() {
+        return "Column[width=" + width +"]";
+    }
 }

graphics-pdfbox-layout/src/main/java/org/xbib/graphics/pdfbox/layout/table/Row.java

@@ -88,6 +88,10 @@ public class Row {
         this.height += (this.height / (heightOfHighestCell - rowSpanSizeDifference)) * rowSpanSizeDifference;
     }
 
+    public String toString() {
+        return cells.toString();
+    }
+
     public static Builder builder() {
         return new Builder();
     }

graphics-pdfbox-layout/src/main/java/org/xbib/graphics/pdfbox/layout/table/Table.java

@@ -285,7 +285,8 @@ public class Table {
         public Table build() {
             if (getNumberOfRegularCells() != getNumberOfSpannedCells()) {
                 throw new TableSetupException("Number of table cells does not match with table setup. " +
-                        "This could be due to row or col spanning not being correct");
+                        "Number of regular cells = " + getNumberOfRegularCells() + ", number of spanned cells = " + getNumberOfSpannedCells() +
+                        ". This could be due to row or col spanning not being correct. Rows = " + rows);
             }
             Table table = new Table(rows, columns, rowSpanCells);
             table.setSettings(parameters);

graphics-pdfbox-layout/src/main/java/org/xbib/graphics/pdfbox/layout/table/TextCell.java

@@ -23,6 +23,11 @@ public class TextCell extends AbstractTextCell {
         return text;
     }
 
+    @Override
+    public String toString() {
+        return "Cell:" + getText() + "[colspan=" + getColSpan() + ",rowspan=" + getRowSpan() + "]";
+    }
+
     public static Builder builder() {
         return new Builder();
     }