PDFBOX-2941: remove empty lines, set indent to 2

git-svn-id: https://svn.apache.org/repos/asf/pdfbox/trunk@1930288 13f79535-47bb-0310-9956-ffa450edef68

Author: THausherr

debugger/src/main/java/org/apache/pdfbox/debugger/streampane/StreamPane.java

@@ -383,12 +383,13 @@ private StyledDocument getXMLDocument(InputStream inputStream)
                     transformerFactory.setAttribute(XMLConstants.ACCESS_EXTERNAL_STYLESHEET, "");
                     Transformer transformer = transformerFactory.newTransformer();
                     transformer.setOutputProperty(OutputKeys.INDENT, "yes");
-                    transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "1");
+                    transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "2");
                     StringWriter sw = new StringWriter();
                     StreamResult result = new StreamResult(sw);
                     DOMSource source = new DOMSource(doc);
                     transformer.transform(source, result);
-                    docu.insertString(0, sw.toString(), null);
+                    // replaceAll because of JDK-8262285. Alternatively pass an XSLT to newTransformer()
+                    docu.insertString(0, sw.toString().replaceAll("(\\r\\n|\\r|\\n) +(\\r\\n|\\r|\\n)","\n"), null);
                 }
                 catch (IOException | TransformerFactoryConfigurationError | IllegalArgumentException |
                        TransformerException | BadLocationException ex)