add check compressor's byte size when finish compress

Author: famosss

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/io/compress/BlockCompressorStream.java

@@ -135,7 +135,7 @@ public void write(byte[] b, int off, int len) throws IOException {
 
   @Override
   public void finish() throws IOException {
-    if (!compressor.finished()) {
+    if (!compressor.finished() && compressor.getBytesRead() > 0) {
       rawWriteInt((int)compressor.getBytesRead());
       compressor.finish();
       while (!compressor.finished()) {