Fix #21: Show error when RegistrationHandler.classes empty (#67)

show an error message when RegistrationHandler.classes is empty

Author: shobhanmandal

java/source/org/libreoffice/ide/eclipse/java/JavaResourceDeltaVisitor.java

@@ -116,6 +116,8 @@ private void removeImplementation(IResourceDelta pDelta,
                     RegistrationHelper.removeImplementation(pUnoprj, implName);
                 }
             }
+        } else if (res.getName().endsWith(".jar")) {
+            RegistrationHelper.isFileEmpty(pUnoprj);
         }
     }
 

java/source/org/libreoffice/ide/eclipse/java/registration/RegistrationHelper.java

@@ -55,6 +55,8 @@
 import org.eclipse.core.resources.IFile;
 import org.eclipse.core.resources.IFolder;
 import org.eclipse.core.runtime.IPath;
+import org.eclipse.jface.dialogs.MessageDialog;
+import org.eclipse.swt.widgets.Display;
 import org.libreoffice.ide.eclipse.core.PluginLogger;
 import org.libreoffice.ide.eclipse.core.model.IUnoidlProject;
 import org.libreoffice.ide.eclipse.java.utils.TemplatesHelper;
@@ -228,4 +230,41 @@ private static IFile getClassesListFile(IUnoidlProject pProject) {
 
         return dest.getFile("RegistrationHandler.classes"); //$NON-NLS-1$
     }
+
+    /**
+     * Check if the RegistrationHandler.classes file is empty
+     * <code>org.libreoffice.ide.eclipse.java.JavaResourceDeltaVisitor</code>
+     *
+     * @param pProject the project where to check empty file
+     */
+    public static void isFileEmpty(IUnoidlProject pProject) {
+        IFile list = getClassesListFile(pProject);
+        File file = list.getLocation().toFile();
+        boolean checkFileEmpty = true;
+        FileInputStream in = null;
+        BufferedReader reader = null;
+        try {
+            in = new FileInputStream(file);
+            reader = new BufferedReader(new InputStreamReader(in));
+            if (reader.readLine() == null) {
+                checkFileEmpty = true;
+            } else {
+                checkFileEmpty = false;
+            }
+        } catch (Exception e) {
+            checkFileEmpty = true;
+
+        } finally {
+            try {
+                reader.close();
+                in.close();
+            } catch (Exception e) {
+            }
+        }
+        if (checkFileEmpty) {
+            PluginLogger.error(Messages.getString("RegistrationHelper.RegistrationHandlerEmptyClassError"));
+            MessageDialog.openError(Display.getDefault().getActiveShell(), "Error",
+                Messages.getString("RegistrationHelper.RegistrationHandlerEmptyClassError"));
+        }
+    }
 }

java/source/org/libreoffice/ide/eclipse/java/registration/messages.properties

@@ -1,2 +1,4 @@
 FileRefreshJob.Error=Can't refresh the registration classes file
 RegistrationHelper.WriteClassesListError=Error during classes list writing
+RegistrationHelper.RegistrationHandlerEmptyClassError=The RegistrationHandler.classes is empty, exported .oxt extension will not work properly
+