拉去dev到heart, 补充提交

epmet-commons/epmet-commons-tools/src/main/java/com/epmet/commons/tools/utils/HttpClientManager.java

@@ -32,6 +32,7 @@ import org.springframework.util.CollectionUtils;
 import javax.crypto.Mac;
 import javax.crypto.spec.SecretKeySpec;
 import java.io.ByteArrayOutputStream;
+import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
 import java.net.URLEncoder;