eu.etaxonomy.taxeditor.store/src/main/java/eu/etaxonomy/taxeditor/model/MementoHelper.java

   1 // $Id$
   2 /**
   3 * Copyright (C) 2007 EDIT
   4 * European Distributed Institute of Taxonomy
   5 * http://www.e-taxonomy.eu
   6 *
   7 * The contents of this file are subject to the Mozilla Public License Version 1.1
   8 * See LICENSE.TXT at the top of this package for the full license terms.
   9 */
  10
  11 package eu.etaxonomy.taxeditor.model;
  12
  13 import java.io.BufferedReader;
  14 import java.io.File;
  15 import java.io.FileInputStream;
  16 import java.io.FileNotFoundException;
  17 import java.io.FileOutputStream;
  18 import java.io.IOException;
  19 import java.io.InputStreamReader;
  20 import java.io.OutputStreamWriter;
  21 import java.io.UnsupportedEncodingException;
  22
  23 import org.eclipse.ui.IMemento;
  24 import org.eclipse.ui.WorkbenchException;
  25 import org.eclipse.ui.XMLMemento;
  26
  27 import eu.etaxonomy.taxeditor.store.StoreUtil;
  28
  29 /**
  30  * <p>MementoHelper class.</p>
  31  *
  32  * @author n.hoffmann
  33  * @created Mar 29, 2010
  34  * @version 1.0
  35  */
  36 public class MementoHelper {
  37
  38         /**
  39          * <p>readMementoFromFile</p>
  40          *
  41          * @param stateFile a {@link java.io.File} object.
  42          * @return a org.eclipse.ui.IMemento object.
  43          * @throws java.io.FileNotFoundException if any.
  44          */
  45         public static IMemento readMementoFromFile(File stateFile) throws FileNotFoundException{
  46                 FileInputStream input;
  47                 try {
  48                         input = new FileInputStream(stateFile);
  49                         BufferedReader reader = new BufferedReader(
  50                                         new InputStreamReader(input, "utf-8")); //$NON-NLS-1$
  51                         return XMLMemento.createReadRoot(reader);
  52                 } catch (WorkbenchException e) {
  53                         StoreUtil.error(MementoHelper.class, "Exception while reading the memento", e);
  54                 } catch (UnsupportedEncodingException e) {
  55                         StoreUtil.error(MementoHelper.class, "Exception while reading the memento", e);
  56                 }
  57
  58                 return null;
  59         }
  60
  61         /*
  62          * Save the workbench UI in a persistence file.
  63          */
  64         /**
  65          * <p>saveMementoToFile</p>
  66          *
  67          * @param memento a org.eclipse.ui.IMemento object.
  68          * @param stateFile a {@link java.io.File} object.
  69          * @return a org.eclipse.ui.IMemento object.
  70          */
  71         public static IMemento saveMementoToFile(IMemento memento, File stateFile) {
  72                 if (stateFile == null || memento == null) {
  73                         return null;
  74                 }
  75                 try {
  76                         FileOutputStream stream = new FileOutputStream(stateFile);
  77                         OutputStreamWriter writer = new OutputStreamWriter(stream, "utf-8"); //$NON-NLS-1$
  78
  79                         ((XMLMemento)memento).save(writer);
  80
  81                         writer.close();
  82                 } catch (IOException e) {
  83                         stateFile.delete();
  84                         StoreUtil.error(MementoHelper.class, "Could not save datasource state", e);
  85                         return null;
  86                 }
  87
  88                 // Success !
  89                 return memento;
  90         }
  91 }