Extend CustomWordPlaceholderData to insert into header/footer

Up until now, the processing flow when inserting a paragraph into
a header or footer lead to a `ClassCastException`, as
jocument assumed that the insertion happened into a
`XWPFDocument`.
To fix this, the abstract method for transforming a placeholder
now expects an `IBody` element instead of a `XWPFDocument`, where
`IBody` is an interface which describes the possible insertion
methods.
This allows jocument to insert paragraphs into any kind of
xwpf part.

build.gradle

@@ -8,7 +8,7 @@ plugins {
 }
 
 group 'com.docutools'
-version = '1.8.0'
+version = '2.0.0'
 
 java {
     toolchain {

src/main/java/com/docutools/jocument/impl/word/CustomWordPlaceholderData.java

@@ -6,8 +6,8 @@
 import java.util.Locale;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.apache.poi.xwpf.usermodel.IBody;
 import org.apache.poi.xwpf.usermodel.IBodyElement;
-import org.apache.poi.xwpf.usermodel.XWPFDocument;
 
 public abstract class CustomWordPlaceholderData implements PlaceholderData {
   private static final Logger logger = LogManager.getLogger();
@@ -19,16 +19,18 @@ public PlaceholderType getType() {
 
   @Override
   public void transform(Object placeholder, Locale locale, GenerationOptions options) {
-    if (!(placeholder instanceof IBodyElement element)) {
+    if (placeholder instanceof IBodyElement element) {
+      if (element.getPart() instanceof IBody bodyPart) {
+        transform(element, bodyPart, locale, options);
+      } else {
+        logger.error("Parent of {} is not an instance of IBody", placeholder);
+        throw new IllegalArgumentException("Only children of IBody objects accepted.");
+      }
+    } else {
       logger.error("{} is not an instance of IBodyElement", placeholder);
       throw new IllegalArgumentException("Only IBodyElements accepted.");
     }
-
-    var document = element.getBody().getXWPFDocument();
-
-    transform(element, document, locale, options);
   }
 
-  protected abstract void transform(IBodyElement placeholder, XWPFDocument document, Locale locale, GenerationOptions options);
-
+  protected abstract void transform(IBodyElement placeholder, IBody part, Locale locale, GenerationOptions options);
 }

src/main/java/com/docutools/jocument/impl/word/placeholders/ImagePlaceholderData.java

@@ -10,8 +10,8 @@
 import java.util.Locale;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.apache.poi.xwpf.usermodel.IBody;
 import org.apache.poi.xwpf.usermodel.IBodyElement;
-import org.apache.poi.xwpf.usermodel.XWPFDocument;
 
 public class ImagePlaceholderData extends CustomWordPlaceholderData {
   private static final Logger logger = LogManager.getLogger();
@@ -31,10 +31,10 @@ public ImagePlaceholderData withMaxWidth(int maxWidth) {
   }
 
   @Override
-  protected void transform(IBodyElement placeholder, XWPFDocument document, Locale locale, GenerationOptions options) {
+  protected void transform(IBodyElement placeholder, IBody part, Locale locale, GenerationOptions options) {
     Path path = applyOptions(options);
     try {
-      var paragraph = document.insertNewParagraph(WordUtilities.openCursor(placeholder).orElseThrow());
+      var paragraph = part.insertNewParagraph(WordUtilities.openCursor(placeholder).orElseThrow());
       WordImageUtils.insertImage(paragraph, path, options.imageStrategy());
       WordUtilities.removeIfExists(placeholder);
     } finally {

src/test/java/com/docutools/jocument/impl/word/WordGeneratorTest.java

@@ -512,4 +512,20 @@ void dynamicAccess() throws InterruptedException, IOException {
         assertThat(documentWrapper.bodyElement(0).asParagraph().run(0).text(), equalTo(SampleModelData.ENTERPRISE.name()));
     }
 
+    @Test
+    void pictureInHeader() throws InterruptedException, IOException {
+        // Arrange
+        Template template = Template.fromClassPath("/templates/word/PictureInHeader.docx")
+            .orElseThrow();
+        PlaceholderResolver resolver = new ReflectionResolver(SampleModelData.PICARD);
+
+        // Act
+        Document document = template.startGeneration(resolver);
+        document.blockUntilCompletion(60000L); // 1 minute
+
+        // Assert
+        assertThat(document.completed(), is(true));
+        xwpfDocument = TestUtils.getXWPFDocumentFromDocument(document);
+        assertThat(xwpfDocument.getHeaderArray(0).getAllPictures(), hasSize(1));
+    }
 }

src/test/java/com/docutools/jocument/localisation/CustomTranslationsTests.java

@@ -15,6 +15,7 @@
 import com.docutools.jocument.sample.model.SampleModelData;
 import java.util.Locale;
 import java.util.Optional;
+import org.apache.poi.xwpf.usermodel.IBody;
 import org.apache.poi.xwpf.usermodel.IBodyElement;
 import org.apache.poi.xwpf.usermodel.XWPFDocument;
 import org.apache.poi.xwpf.usermodel.XWPFParagraph;
@@ -103,7 +104,7 @@ public CustomTranslatedPlaceholder() {
     }
 
     @Override
-    protected void transform(IBodyElement placeholder, XWPFDocument document, Locale locale, GenerationOptions options) {
+    protected void transform(IBodyElement placeholder, IBody part, Locale locale, GenerationOptions options) {
       if (placeholder instanceof XWPFParagraph paragraph) {
         var translatedText = options.translate(paragraph.getText(), locale).orElse("");
         WordUtilities.replaceText(paragraph, translatedText);

src/test/java/com/docutools/jocument/sample/placeholders/QuotePlaceholder.java

@@ -4,13 +4,13 @@
 import com.docutools.jocument.impl.word.CustomWordPlaceholderData;
 import com.docutools.jocument.impl.word.WordUtilities;
 import java.util.Locale;
+import org.apache.poi.xwpf.usermodel.IBody;
 import org.apache.poi.xwpf.usermodel.IBodyElement;
-import org.apache.poi.xwpf.usermodel.XWPFDocument;
 
 public class QuotePlaceholder extends CustomWordPlaceholderData {
   @Override
-  protected void transform(IBodyElement placeholder, XWPFDocument document, Locale locale, GenerationOptions options) {
-    var paragraph = document.insertNewParagraph(WordUtilities.openCursor(placeholder).orElseThrow());
+  protected void transform(IBodyElement placeholder, IBody part, Locale locale, GenerationOptions options) {
+    var paragraph = part.insertNewParagraph(WordUtilities.openCursor(placeholder).orElseThrow());
     paragraph.createRun().setText("Live your life not celebrating victories, but overcoming defeats.");
     WordUtilities.removeIfExists(placeholder);
   }