Add getAsPdfObject to IPdfFunction to avoid casting

DEVSIX-3538

Author: glenn.volckaert

kernel/src/main/java/com/itextpdf/kernel/pdf/colorspace/PdfSpecialCs.java

@@ -52,7 +52,6 @@ This file is part of the iText (R) project.
 import com.itextpdf.kernel.pdf.PdfNumber;
 import com.itextpdf.kernel.pdf.PdfObject;
 import com.itextpdf.kernel.pdf.PdfString;
-import com.itextpdf.kernel.pdf.function.AbstractPdfFunction;
 import com.itextpdf.kernel.pdf.function.IPdfFunction;
 import com.itextpdf.kernel.pdf.function.PdfFunction;
 import com.itextpdf.kernel.pdf.function.PdfFunctionFactory;
@@ -155,7 +154,7 @@ public Separation(String name, PdfColorSpace alternateSpace, PdfFunction tintTra
          */
         public Separation(String name, PdfColorSpace alternateSpace, IPdfFunction tintTransform) {
             this(new PdfName(name), alternateSpace.getPdfObject(),
-                    ((AbstractPdfFunction<PdfDictionary>)tintTransform).getPdfObject());
+                    tintTransform.getAsPdfObject());
             if (!tintTransform.checkCompatibilityWithColorSpace(alternateSpace)) {
                 throw new PdfException(
                         KernelExceptionMessageConstant.FUNCTION_IS_NOT_COMPATIBLE_WITH_COLOR_SPACE, this);
@@ -238,7 +237,7 @@ public DeviceN(List<String> names, PdfColorSpace alternateSpace, PdfFunction tin
          */
         public DeviceN(List<String> names, PdfColorSpace alternateSpace, IPdfFunction tintTransform) {
             this(new PdfArray(names, true), alternateSpace.getPdfObject(),
-                    ((AbstractPdfFunction<PdfDictionary>)tintTransform).getPdfObject());
+                    tintTransform.getAsPdfObject());
             if (tintTransform.getInputSize() != numOfComponents ||
                     tintTransform.getOutputSize() != alternateSpace.getNumberOfComponents()) {
                 throw new PdfException(
@@ -313,7 +312,7 @@ public NChannel(List<String> names, PdfColorSpace alternateSpace, PdfFunction ti
         public NChannel(List<String> names, PdfColorSpace alternateSpace, IPdfFunction tintTransform,
                 PdfDictionary attributes) {
             this(new PdfArray(names, true), alternateSpace.getPdfObject(),
-                    ((AbstractPdfFunction<PdfDictionary>)tintTransform).getPdfObject(), attributes);
+                    tintTransform.getAsPdfObject(), attributes);
             if (tintTransform.getInputSize() != 1 ||
                     tintTransform.getOutputSize() != alternateSpace.getNumberOfComponents()) {
                 throw new PdfException(

kernel/src/main/java/com/itextpdf/kernel/pdf/function/AbstractPdfFunction.java

@@ -48,6 +48,7 @@ This file is part of the iText (R) project.
 import com.itextpdf.kernel.pdf.PdfDictionary;
 import com.itextpdf.kernel.pdf.PdfName;
 import com.itextpdf.kernel.pdf.PdfNumber;
+import com.itextpdf.kernel.pdf.PdfObject;
 import com.itextpdf.kernel.pdf.PdfObjectWrapper;
 import com.itextpdf.kernel.pdf.PdfStream;
 import com.itextpdf.kernel.pdf.colorspace.PdfColorSpace;
@@ -105,14 +106,6 @@ protected AbstractPdfFunction(T pdfObject) {
         range = rangeObj == null ? null : rangeObj.toDoubleArray();
     }
 
-    /**
-     * The function type, (see ISO-320001 Table 38)
-        functionType = pdfObject.getAsNumber(PdfName.FunctionType).intValue();
-        domain = pdfObject.getAsArray(PdfName.Domain).toDoubleArray();
-        final PdfArray rangeObj = pdfObject.getAsArray(PdfName.Range);
-        range = rangeObj == null ? null : rangeObj.toDoubleArray();
-    }
-
     /**
      * The function type, (see ISO-320001 Table 38).
      *
@@ -283,7 +276,6 @@ public byte[] calculateFromByteArray(byte[] bytes, int offset, int length, int w
         return actualOutputConvertor.convert(outValues);
     }
 
-
     /**
      * Clip input values to the allowed domain.
      *
@@ -324,6 +316,11 @@ public double[] clipOutput(double[] input) {
         return clip(input, range);
     }
 
+    @Override
+    public PdfObject getAsPdfObject() {
+        return super.getPdfObject();
+    }
+
     protected static double[] clip(double[] values, double[] limits) {
         assert (values.length * 2 == limits.length);
 

kernel/src/main/java/com/itextpdf/kernel/pdf/function/IPdfFunction.java

@@ -43,6 +43,7 @@ This file is part of the iText (R) project.
  */
 package com.itextpdf.kernel.pdf.function;
 
+import com.itextpdf.kernel.pdf.PdfObject;
 import com.itextpdf.kernel.pdf.colorspace.PdfColorSpace;
 import com.itextpdf.kernel.pdf.function.BaseInputOutPutConvertors.IInputConversionFunction;
 import com.itextpdf.kernel.pdf.function.BaseInputOutPutConvertors.IOutputConversionFunction;
@@ -86,4 +87,6 @@ byte[] calculateFromByteArray(byte[] bytes, int offset, int length, int wordSize
     double[] clipInput(double[] input);
 
     double[] clipOutput(double[] input);
+
+    PdfObject getAsPdfObject();
 }