使用GEOTools为shp文件写入数据

在上一篇我们已经建立了一个空的shp文件，接着我们为这个空文件装入数据，这个功能主要用到SimplefeatureStore.addFeatures()这个方法，传入的属性是Transaction transaction = new DefaultTransaction(null)，这里的null是可以设置string类型的值的，这个值有什么影响还不清楚，求助大神！

以下是装载数据的代码：

      File SHPfilepath=new File("E:\\workspace");

      File SHPfile = JFileDataStoreChooser.showOpenFile("shp", SHPfilepath, null);

          if (SHPfile == null) 

          {

              return;

          }

         FileDataStore store = FileDataStoreFinder.getDataStore(SHPfile);

         String typeName = store.getTypeNames()[0];

         JOptionPane.showMessageDialog(null, "This is the typeName="+typeName);

        SimpleFeatureSource featureSource = store.getFeatureSource(typeName);

      SimpleFeatureStore SimplefeatureStore = (SimpleFeatureStore) featureSource;

      SimpleFeatureCollection SimpleFeaturecollection = new ListFeatureCollection(TYPE, features);

       

      Transaction transaction = new DefaultTransaction(null);  

      SimplefeatureStore.setTransaction(transaction);

            try 

            {

            SimplefeatureStore.addFeatures(SimpleFeaturecollection);

                transaction.commit();

                JOptionPane.showMessageDialog(null, "The points have been adden into shipfile!");

            } 

            catch (Exception problem)

            {

                problem.printStackTrace();

                transaction.rollback();

            } 

            finally 

            {

                transaction.close();

            }

            System.exit(0);   

   }