FileHandler.java

   1 package org.argeo.eclipse.ui.specific;
   2
   3 import java.awt.Desktop;
   4 import java.io.File;
   5 import java.io.FileOutputStream;
   6 import java.io.IOException;
   7 import java.io.InputStream;
   8 import java.io.OutputStream;
   9
  10 import org.apache.commons.io.IOUtils;
  11 import org.argeo.ArgeoException;
  12
  13 /**
  14  * Abstraction that enable to implement runtime environment specific (typically
  15  * RCP or RAP) methods while dealing with files in the UI.
  16  *
  17  */
  18 public class FileHandler {
  19
  20         private FileProvider provider;
  21
  22         public FileHandler(FileProvider provider) {
  23                 this.provider = provider;
  24         }
  25
  26         public void openFile(String fileName, String fileId) {
  27                 String tmpFileName = fileName;
  28                 String prefix = "", extension = "";
  29                 if (fileName != null) {
  30                         int ind = fileName.lastIndexOf('.');
  31                         if (ind > 0) {
  32                                 prefix = fileName.substring(0, ind);
  33                                 extension = fileName.substring(ind);
  34                         }
  35                 }
  36
  37                 InputStream is = null;
  38                 try {
  39                         is = provider.getInputStreamFromFileId(fileId);
  40                         File file = createTmpFile(prefix, extension, is);
  41                         tmpFileName = file.getName();
  42                         Desktop desktop = null;
  43                         if (Desktop.isDesktopSupported()) {
  44                                 desktop = Desktop.getDesktop();
  45                         }
  46                         desktop.open(file);
  47                 } catch (IOException e) {
  48                         // Note : tmpFileName = fileName if the error has been thrown while
  49                         // creating the tmpFile.
  50                         throw new ArgeoException("Cannot open file " + tmpFileName, e);
  51                 } finally {
  52                         IOUtils.closeQuietly(is);
  53                 }
  54         }
  55
  56         private File createTmpFile(String prefix, String suffix, InputStream is) {
  57                 File tmpFile = null;
  58                 OutputStream os = null;
  59                 try {
  60                         tmpFile = File.createTempFile(prefix, suffix);
  61                         os = new FileOutputStream(tmpFile);
  62                         IOUtils.copy(is, os);
  63                 } catch (IOException e) {
  64                         throw new ArgeoException("Cannot open file " + prefix + "."
  65                                         + suffix, e);
  66                 } finally {
  67                         IOUtils.closeQuietly(os);
  68                 }
  69                 return tmpFile;
  70         }
  71 }