BAEL-3826: test Thymeleaf PDF generation using ByteArrayOutputStream

pdf/src/test/java/com/baeldung/pdf/PDFThymeleafUnitTest.java

@@ -0,0 +1,50 @@
+package com.baeldung.pdf;
+
+import com.lowagie.text.DocumentException;
+import org.junit.Test;
+import org.thymeleaf.TemplateEngine;
+import org.thymeleaf.context.Context;
+import org.thymeleaf.templatemode.TemplateMode;
+import org.thymeleaf.templateresolver.ClassLoaderTemplateResolver;
+import org.xhtmlrenderer.pdf.ITextRenderer;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+
+import static org.junit.Assert.assertTrue;
+
+public class PDFThymeleafUnitTest {
+
+    @Test
+    public void givenThymeleafTemplate_whenParsedAndRenderedToPDF_thenItShouldNotBeEmpty() throws DocumentException, IOException {
+        String html = parseThymeleafTemplate();
+        ByteArrayOutputStream outputStream = generatePdfOutputStreamFromHtml(html);
+        assertTrue(outputStream.size() > 0);
+    }
+
+    private ByteArrayOutputStream generatePdfOutputStreamFromHtml(String html) throws IOException, DocumentException {
+        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+
+        ITextRenderer renderer = new ITextRenderer();
+        renderer.setDocumentFromString(html);
+        renderer.layout();
+        renderer.createPDF(outputStream);
+
+        outputStream.close();
+        return outputStream;
+    }
+
+    private String parseThymeleafTemplate() {
+        ClassLoaderTemplateResolver templateResolver = new ClassLoaderTemplateResolver();
+        templateResolver.setSuffix(".html");
+        templateResolver.setTemplateMode(TemplateMode.HTML);
+
+        TemplateEngine templateEngine = new TemplateEngine();
+        templateEngine.setTemplateResolver(templateResolver);
+
+        Context context = new Context();
+        context.setVariable("to", "Baeldung.com");
+
+        return templateEngine.process("thymeleaf_template", context);
+    }
+}