Merge branch 'develop' into features/JAL-250_hideredundantseqs

[jalview.git] / src / jalview / ws / utils / UrlDownloadClient.java

diff --git a/src/jalview/ws/utils/UrlDownloadClient.java b/src/jalview/ws/utils/UrlDownloadClient.java
new file mode 100644 (file)
index 0000000..448edd9
--- /dev/null
+++ b/src/jalview/ws/utils/UrlDownloadClient.java
@@ -0,0 +1,110 @@
+/*
+ * Jalview - A Sequence Alignment Editor and Viewer ($$Version-Rel$$)
+ * Copyright (C) $$Year-Rel$$ The Jalview Authors
+ * 
+ * This file is part of Jalview.
+ * 
+ * Jalview is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License 
+ * as published by the Free Software Foundation, either version 3
+ * of the License, or (at your option) any later version.
+ *  
+ * Jalview is distributed in the hope that it will be useful, but 
+ * WITHOUT ANY WARRANTY; without even the implied warranty 
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR 
+ * PURPOSE.  See the GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with Jalview.  If not, see <http://www.gnu.org/licenses/>.
+ * The Jalview Authors are detailed in the 'AUTHORS' file.
+ */
+
+package jalview.ws.utils;
+
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.net.URL;
+import java.nio.channels.Channels;
+import java.nio.channels.ReadableByteChannel;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.StandardCopyOption;
+
+public class UrlDownloadClient
+{
+  public UrlDownloadClient()
+  {
+
+  }
+
+  /**
+   * Download and save a file from a URL
+   * 
+   * @param urlstring
+   *          url to download from, as string
+   * @param outfile
+   *          the name of file to save the URLs to
+   * @throws IOException
+   */
+  public static void download(String urlstring, String outfile)
+          throws IOException
+  {
+    FileOutputStream fos = null;
+    ReadableByteChannel rbc = null;
+    Path temp = null;
+    try
+    {
+      temp = Files.createTempFile(".jalview_", ".tmp");
+
+      URL url = new URL(urlstring);
+      rbc = Channels.newChannel(url.openStream());
+      fos = new FileOutputStream(temp.toString());
+      fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
+
+      // copy tempfile to outfile once our download completes
+      // incase something goes wrong
+      Files.copy(temp, Paths.get(outfile),
+              StandardCopyOption.REPLACE_EXISTING);
+    } catch (IOException e)
+    {
+      throw e;
+    } finally
+    {
+      try
+      {
+        if (fos != null)
+        {
+          fos.close();
+        }
+      } catch (IOException e)
+      {
+        System.out.println(
+                "Exception while closing download file output stream: "
+                        + e.getMessage());
+      }
+      try
+      {
+        if (rbc != null)
+        {
+          rbc.close();
+        }
+      } catch (IOException e)
+      {
+        System.out.println("Exception while closing download channel: "
+                + e.getMessage());
+      }
+      try
+      {
+        if (temp != null)
+        {
+          Files.deleteIfExists(temp);
+        }
+      } catch (IOException e)
+      {
+        System.out.println("Exception while deleting download temp file: "
+                + e.getMessage());
+      }
+    }
+  }
+}