Fixed "Sometimes multipart body missed last 1 byte." AsyncHttpClient#1271 and added the testcase. (AsyncHttpClient#1275)

Author: carryel

src/main/java/com/ning/http/client/multipart/MultipartBody.java

@@ -183,7 +183,7 @@ public long read(ByteBuffer buffer) throws IOException {
     }
 
     private boolean currentBytesFullyRead() {
-        return currentBytes == null || currentBytesPosition >= currentBytes.length - 1;
+        return currentBytes == null || currentBytesPosition == -1;
     }
 
     private void initializeFileBody(AbstractFilePart part) throws IOException {

src/test/java/com/ning/http/client/multipart/MultipartBodyTest.java

@@ -40,6 +40,16 @@ public void transferWithCopy() throws IOException {
         }
     }
 
+    @Test
+    public void transferWithCopy2() throws IOException {
+        try (final MultipartBody multipartBody = buildMultipart()) {
+            final long contentLength = multipartBody.getContentLength();
+            final int bufferSize = (int)contentLength - 1;
+            final long tranferred = transferWithCopy(multipartBody, bufferSize);
+            Assert.assertEquals(tranferred, contentLength);
+        }
+    }
+
     @Test
     public void transferZeroCopy() throws IOException {
         try (MultipartBody multipartBody = buildMultipart()) {
@@ -70,8 +80,11 @@ private static File getTestfile() {
     }
 
     private static long transferWithCopy(MultipartBody multipartBody) throws IOException {
+        return transferWithCopy(multipartBody, 8192);
+    }
 
-        final ByteBuffer buffer = ByteBuffer.allocate(8192);
+    private static long transferWithCopy(MultipartBody multipartBody, int bufferSize) throws IOException {
+        final ByteBuffer buffer = ByteBuffer.allocate(bufferSize);
         long totalBytes = 0;
         while (true) {
             long readBytes = multipartBody.read(buffer);