diff --git a/src/java/net/jpountz/lz4/LZ4FrameInputStream.java b/src/java/net/jpountz/lz4/LZ4FrameInputStream.java
index 4a75bac..918f556 100644
--- a/src/java/net/jpountz/lz4/LZ4FrameInputStream.java
+++ b/src/java/net/jpountz/lz4/LZ4FrameInputStream.java
@@ -380,6 +380,8 @@ public long skip(long n) throws IOException {
 
   @Override
   public int available() throws IOException {
+    //增加空判断，避免buffer为null时抛出 NullPointerException
+    if (null == buffer) return 0;
     return buffer.remaining();
   }