fix some more checkstyle warnings

Author: snisnisniksonah

src/main/java/org/jabref/gui/fieldeditors/HtmlTransferable.java

@@ -19,15 +19,12 @@ public class HtmlTransferable implements Transferable {
 
     public static final DataFlavor HTML_FLAVOR = new DataFlavor("text/html;charset=utf-8;class=java.lang.String", "HTML Format");
     public static final DataFlavor TEXT_FLAVOR = DataFlavor.stringFlavor;
-
     private static final List<DataFlavor> ALL_FLAVORS = Arrays.asList(HTML_FLAVOR, DataFlavor.allHtmlFlavor, TEXT_FLAVOR);
-
     private static final Pattern HTML_NEWLINE = Pattern.compile(" ?<br>|<BR>");
     private static final Pattern REMOVE_HTML = Pattern.compile("<(?!br)(?!BR).*?>");
     private static final Pattern WHITESPACE_AROUND_NEWLINE = Pattern.compile("(?m)^\\s+|\\v+");
     private static final Pattern DOUBLE_WHITESPACES = Pattern.compile("[ ]{2,}");
     private final String htmlText;
-
     private final String plainText;
 
     public HtmlTransferable(String html) {

src/main/java/org/jabref/gui/fieldeditors/JournalEditor.java

@@ -12,7 +12,6 @@
 import org.jabref.logic.journals.JournalAbbreviationPreferences;
 import org.jabref.model.entry.BibEntry;
 
-
 public class JournalEditor extends HBox implements FieldEditorFX {
 
     private final String fieldName;

src/main/java/org/jabref/gui/fieldeditors/OwnerEditor.java

@@ -11,7 +11,6 @@
 import org.jabref.model.entry.BibEntry;
 import org.jabref.preferences.JabRefPreferences;
 
-
 public class OwnerEditor extends HBox implements FieldEditorFX {
 
     private final String fieldName;

src/main/java/org/jabref/gui/fieldeditors/UrlEditor.java

@@ -11,7 +11,6 @@
 import org.jabref.gui.util.ControlHelper;
 import org.jabref.model.entry.BibEntry;
 
-
 public class UrlEditor extends HBox implements FieldEditorFX {
 
     private final String fieldName;