Added check into BufferedChannel's read to avoid endless loop if dest…

… buffer's remaining capacity is not as much as length

bookkeeper-server/src/main/java/org/apache/bookkeeper/bookie/BufferedChannel.java

@@ -243,6 +243,11 @@ public long forceWrite(boolean forceMetadata) throws IOException {
 
     @Override
     public synchronized int read(ByteBuf dest, long pos, int length) throws IOException {
+        if(dest.writableBytes() < length) {
+            throw new IllegalArgumentException("dest buffer remaining capacity is not enough" +
+                    "(must be at least as \"length\"=" + length +")");
+        }
+
         long prevPos = pos;
         while (length > 0) {
             // check if it is in the write buffer