Egads, don't share a download buffer.

Fragile assumptions, they plague us.

Fixes #166

core/src/main/java/com/threerings/getdown/net/DownloadAbortedException.java

@@ -1,15 +0,0 @@
-//
-// Getdown - application installer, patcher and launcher
-// Copyright (C) 2004-2016 Getdown authors
-// https://github.com/threerings/getdown/blob/master/LICENSE
-
-package com.threerings.getdown.net;
-
-import java.io.IOException;
-
-/**
- * Used to terminate the download process in its midst.
- */
-public class DownloadAbortedException extends IOException
-{
-}

core/src/main/java/com/threerings/getdown/net/Downloader.java

@@ -211,9 +211,6 @@ public abstract class Downloader
     /** The bytes downloaded for each resource. */
     protected Map<Resource, Long> _downloaded = new HashMap<>();
 
-    /** Used while downloading. */
-    protected byte[] _buffer = new byte[4096];
-
     /** The time at which the file transfer began. */
     protected long _start;
 

core/src/main/java/com/threerings/getdown/net/HTTPDownloader.java

@@ -69,6 +69,7 @@ public class HTTPDownloader extends Downloader
             long actualSize = conn.getContentLength();
             log.info("Downloading resource", "url", rsrc.getRemote(), "size", actualSize);
             long currentSize = 0L;
+            byte[] buffer = new byte[4*4096];
             try (InputStream in = conn.getInputStream();
                  FileOutputStream out = new FileOutputStream(rsrc.getLocalNew())) {
 
@@ -78,13 +79,13 @@ public class HTTPDownloader extends Downloader
 
                 // read in the file data
                 int read;
-                while ((read = in.read(_buffer)) != -1) {
+                while ((read = in.read(buffer)) != -1) {
                     // abort the download if the downloader is aborted
                     if (_state == State.ABORTED) {
                         break;
                     }
                     // write it out to our local copy
-                    out.write(_buffer, 0, read);
+                    out.write(buffer, 0, read);
                     // note that we've downloaded some data
                     currentSize += read;
                     reportProgress(rsrc, currentSize, actualSize);