fixed #8 The maximum number of Cell Styles was exceeded

the named cell styles are reused as much as possible

build.gradle

@@ -12,7 +12,7 @@ plugins {
     id 'org.asciidoctor.gradle.asciidoctor' version '1.5.1'
 }
 
-String currentVersion = '0.1.11'
+String currentVersion = '0.1.12'
 
 version = currentVersion
 

spreadsheet-builder-api/src/main/java/org/modelcatalogue/builder/spreadsheet/api/HasStyle.java

@@ -6,6 +6,27 @@
 import groovy.transform.stc.FromString;
 
 public interface HasStyle {
+
+    /**
+     * Applies a customized named style to the current element.
+     *
+     * @param name the name of the style
+     * @param styleDefinition the definition of the style customizing the predefined style
+     */
+    void style(String name, @DelegatesTo(CellStyle.class) @ClosureParams(value=FromString.class, options = "org.modelcatalogue.builder.spreadsheet.api.CellStyle") Closure styleDefinition);
+
+    /**
+     * Applies the style defined by the closure to the current element.
+     * @param styleDefinition the definition of the style
+     */
     void style(@DelegatesTo(CellStyle.class) @ClosureParams(value=FromString.class, options = "org.modelcatalogue.builder.spreadsheet.api.CellStyle") Closure styleDefinition);
+
+    /**
+     * Applies the names style to the current element.
+     *
+     * The style can be changed no longer.
+     *
+     * @param name the name of the style
+     */
     void style(String name);
 }

spreadsheet-builder-poi/src/main/groovy/org/modelcatalogue/builder/spreadsheet/poi/PoiCell.groovy

@@ -119,7 +119,17 @@ class PoiCell extends AbstractCell implements  Resolvable {
 
     @Override
     void style(String name) {
-        style row.sheet.workbook.getStyle(name)
+        if (!poiCellStyle) {
+            poiCellStyle = row.sheet.workbook.getStyle(name)
+            return
+        }
+        poiCellStyle.with row.sheet.workbook.getStyleDefinition(name)
+    }
+
+    @Override
+    void style(String name, @ClosureParams(value=FromString.class, options = "org.modelcatalogue.builder.spreadsheet.api.CellStyle") Closure styleDefinition) {
+        style row.sheet.workbook.getStyleDefinition(name)
+        style styleDefinition
     }
 
     @Override

spreadsheet-builder-poi/src/main/groovy/org/modelcatalogue/builder/spreadsheet/poi/PoiCellStyle.groovy

@@ -26,28 +26,43 @@ import java.util.regex.Matcher
 class PoiCellStyle extends AbstractCellStyle {
 
     private final XSSFCellStyle style
-    private final PoiCell cell
+    private final PoiWorkbook workbook
 
     private PoiFont poiFont
     private PoiBorder poiBorder
 
+    private boolean sealed
+
     PoiCellStyle(PoiCell cell) {
-        this.cell = cell
         if (cell.cell.cellStyle == cell.cell.sheet.workbook.stylesSource.getStyleAt(0)) {
             style = cell.cell.sheet.workbook.createCellStyle() as XSSFCellStyle
             cell.cell.cellStyle = style
         } else {
             style = cell.cell.cellStyle as XSSFCellStyle
         }
+        workbook = cell.row.sheet.workbook
+    }
+
+    PoiCellStyle(PoiWorkbook workbook) {
+        this.style = workbook.workbook.createCellStyle() as XSSFCellStyle
+        this.workbook = workbook
     }
 
     @Override
     void base(String stylename) {
-        with cell.row.sheet.workbook.getStyle(stylename)
+        checkSealed()
+        with workbook.getStyleDefinition(stylename)
+    }
+
+    void checkSealed() {
+        if (sealed) {
+            throw new IllegalStateException("The cell style is already sealed! You need to create new style.")
+        }
     }
 
     @Override
     void background(String hexColor) {
+        checkSealed()
         if (style.fillForegroundColor == IndexedColors.AUTOMATIC.index) {
             foreground hexColor
         } else {
@@ -57,11 +72,13 @@ class PoiCellStyle extends AbstractCellStyle {
 
     @Override
     void background(Color colorPreset) {
+        checkSealed()
         background colorPreset.hex
     }
 
     @Override
     void foreground(String hexColor) {
+        checkSealed()
         if (style.fillForegroundColor != IndexedColors.AUTOMATIC.index) {
             // already set as background color
             style.setFillBackgroundColor(style.getFillForegroundXSSFColor())
@@ -74,11 +91,13 @@ class PoiCellStyle extends AbstractCellStyle {
 
     @Override
     void foreground(Color colorPreset) {
+        checkSealed()
         foreground colorPreset.hex
     }
 
     @Override
     void fill(ForegroundFill fill) {
+        checkSealed()
         switch (fill) {
             case ForegroundFill.NO_FILL:
                 style.fillPattern = CellStyle.NO_FILL
@@ -136,43 +155,50 @@ class PoiCellStyle extends AbstractCellStyle {
 
     @Override
     void font(@DelegatesTo(Font.class) @ClosureParams(value=FromString.class, options = "org.modelcatalogue.builder.spreadsheet.api.Font") Closure fontConfiguration) {
+        checkSealed()
         if (!poiFont) {
-            poiFont = new PoiFont(cell.row.sheet.sheet.workbook, style)
+            poiFont = new PoiFont(workbook.workbook, style)
         }
         poiFont.with fontConfiguration
     }
 
     @Override
     void indent(int indent) {
+        checkSealed()
         style.indention = (short) indent
     }
 
     Object getLocked() {
+        checkSealed()
         style.locked = true
     }
 
     @Override
     void wrap(TextKeyword text) {
+        checkSealed()
         style.wrapText = true
     }
 
     Object getHidden() {
+        checkSealed()
         style.hidden = true
     }
 
     @Override
     void rotation(int rotation) {
+        checkSealed()
         style.rotation = (short) rotation
     }
 
     @Override
     void format(String format) {
-        XSSFDataFormat dataFormat = cell.row.sheet.sheet.workbook.createDataFormat()
+        XSSFDataFormat dataFormat = workbook.workbook.createDataFormat()
         style.dataFormat = dataFormat.getFormat(format)
     }
 
     @Override
     HorizontalAlignmentConfigurer align(VerticalAlignment alignment) {
+        checkSealed()
         switch (alignment) {
             case PureVerticalAlignment.CENTER:
                 style.setVerticalAlignment(org.apache.poi.ss.usermodel.VerticalAlignment.CENTER)
@@ -197,6 +223,7 @@ class PoiCellStyle extends AbstractCellStyle {
 
     @Override
     void border(@DelegatesTo(Border.class) @ClosureParams(value=FromString.class, options = "org.modelcatalogue.builder.spreadsheet.api.Border") Closure borderConfiguration) {
+        checkSealed()
         PoiBorder poiBorder = findOrCreateBorder()
         poiBorder.with borderConfiguration
 
@@ -207,6 +234,7 @@ class PoiCellStyle extends AbstractCellStyle {
 
     @Override
     void border(BorderSide location, @DelegatesTo(Border.class) @ClosureParams(value=FromString.class, options = "org.modelcatalogue.builder.spreadsheet.api.Border") Closure borderConfiguration) {
+        checkSealed()
         PoiBorder poiBorder = findOrCreateBorder()
         poiBorder.with borderConfiguration
         poiBorder.applyTo(location)
@@ -215,7 +243,7 @@ class PoiCellStyle extends AbstractCellStyle {
     @Override
     void border(BorderSide first, BorderSide second,
                 @DelegatesTo(Border.class) @ClosureParams(value=FromString.class, options = "org.modelcatalogue.builder.spreadsheet.api.Border") Closure borderConfiguration) {
-
+        checkSealed()
         PoiBorder poiBorder = findOrCreateBorder()
         poiBorder.with borderConfiguration
         poiBorder.applyTo(first)
@@ -226,7 +254,7 @@ class PoiCellStyle extends AbstractCellStyle {
     @Override
     void border(BorderSide first, BorderSide second, BorderSide third,
                 @DelegatesTo(Border.class) @ClosureParams(value=FromString.class, options = "org.modelcatalogue.builder.spreadsheet.api.Border") Closure borderConfiguration) {
-
+        checkSealed()
         PoiBorder poiBorder = findOrCreateBorder()
         poiBorder.with borderConfiguration
         poiBorder.applyTo(first)
@@ -262,4 +290,8 @@ class PoiCellStyle extends AbstractCellStyle {
 
         new XSSFColor([red, green, blue] as byte[])
     }
+
+    void seal() {
+        this.sealed = true
+    }
 }

spreadsheet-builder-poi/src/main/groovy/org/modelcatalogue/builder/spreadsheet/poi/PoiRow.groovy

@@ -15,7 +15,7 @@ class PoiRow implements Row {
     private final PoiSheet sheet
 
     private String styleName
-    private Closure styleDefinition = { return null }
+    private Closure styleDefinition
 
     private final List<Integer> startPositions = []
     private int nextColNumber = 0
@@ -36,9 +36,15 @@ class PoiRow implements Row {
 
         PoiCell poiCell = new PoiCell(this, xssfCell)
         if (styleName) {
-            poiCell.style styleName
+            if (styleDefinition) {
+                poiCell.style styleName, styleDefinition
+            } else {
+                poiCell.style styleName
+            }
+        } else if(styleDefinition) {
+            poiCell.style styleDefinition
         }
-        poiCell.style styleDefinition
+
         poiCell.value value
 
         poiCell.resolve()
@@ -49,10 +55,17 @@ class PoiRow implements Row {
         XSSFCell xssfCell = xssfRow.createCell(nextColNumber)
 
         PoiCell poiCell = new PoiCell(this, xssfCell)
+
         if (styleName) {
-            poiCell.style styleName
+            if (styleDefinition) {
+                poiCell.style styleName, styleDefinition
+            } else {
+                poiCell.style styleName
+            }
+        } else if (styleDefinition) {
+            poiCell.style styleDefinition
         }
-        poiCell.style styleDefinition
+
         poiCell.with cellDefinition
 
         nextColNumber += poiCell.colspan
@@ -80,10 +93,17 @@ class PoiRow implements Row {
         nextColNumber = column
 
         PoiCell poiCell = new PoiCell(this, xssfCell)
+
         if (styleName) {
-            poiCell.style styleName
+            if (styleDefinition) {
+                poiCell.style styleName, styleDefinition
+            } else {
+                poiCell.style styleName
+            }
+        } else if(styleDefinition) {
+            poiCell.style styleDefinition
         }
-        poiCell.style styleDefinition
+
         poiCell.with cellDefinition
 
         handleSpans(xssfCell, poiCell)
@@ -106,6 +126,12 @@ class PoiRow implements Row {
         this.styleName = name
     }
 
+    @Override
+    void style(String name, @DelegatesTo(CellStyle.class) @ClosureParams(value = FromString.class, options = "org.modelcatalogue.builder.spreadsheet.api.CellStyle") Closure styleDefinition) {
+        style name
+        style styleDefinition
+    }
+
     protected PoiSheet getSheet() {
         return sheet
     }

spreadsheet-builder-poi/src/main/groovy/org/modelcatalogue/builder/spreadsheet/poi/PoiWorkbook.groovy

@@ -4,6 +4,7 @@ import groovy.transform.stc.ClosureParams
 import groovy.transform.stc.FromString
 import org.apache.poi.ss.util.WorkbookUtil
 import org.apache.poi.xssf.usermodel.XSSFCell
+import org.apache.poi.xssf.usermodel.XSSFDataFormat
 import org.apache.poi.xssf.usermodel.XSSFSheet
 import org.apache.poi.xssf.usermodel.XSSFWorkbook
 import org.modelcatalogue.builder.spreadsheet.api.CellStyle
@@ -14,7 +15,9 @@ import org.modelcatalogue.builder.spreadsheet.api.Workbook
 class PoiWorkbook implements Workbook {
 
     private final XSSFWorkbook workbook
-    private final Map<String, Closure> namedStyles = [:]
+    private final Map<String, Closure> namedStylesDefinition = [:]
+    private final Map<String, PoiCellStyle> namedStyles = [:]
+    private final Map<String, XSSFDataFormat> formats = [:]
     private final List<Resolvable> toBeResolved = []
 
     PoiWorkbook(XSSFWorkbook workbook) {
@@ -33,7 +36,7 @@ class PoiWorkbook implements Workbook {
 
     @Override
     void style(String name, @DelegatesTo(CellStyle.class) @ClosureParams(value=FromString.class, options = "org.modelcatalogue.builder.spreadsheet.api.CellStyle") Closure styleDefinition) {
-        namedStyles[name] = styleDefinition
+        namedStylesDefinition[name] = styleDefinition
     }
 
     @Override
@@ -46,8 +49,28 @@ class PoiWorkbook implements Workbook {
         stylesheet.declareStyles(this)
     }
 
-    protected Closure getStyle(String name) {
-        Closure style = namedStyles[name]
+    XSSFWorkbook getWorkbook() {
+        return workbook
+    }
+
+    protected PoiCellStyle getStyle(String name) {
+        PoiCellStyle style = namedStyles[name]
+
+        if (style) {
+            return style
+        }
+
+        style = new PoiCellStyle(this)
+        style.with getStyleDefinition(name)
+        style.seal()
+
+        namedStyles[name] = style
+
+        return style
+    }
+
+    protected Closure getStyleDefinition(String name) {
+        Closure style = namedStylesDefinition[name]
         if (!style) {
             throw new IllegalArgumentException("Style '$name' not defined")
         }