diff --git a/src/adql/parser/ADQLParser.java b/src/adql/parser/ADQLParser.java
index 3bad241ffafe30ad119cbd66168ad9f1d1ea5354..c5833b4b09fd5f1a943ff4db2303d227d7d84540 100644
--- a/src/adql/parser/ADQLParser.java
+++ b/src/adql/parser/ADQLParser.java
@@ -389,7 +389,7 @@ public class ADQLParser implements ADQLParserConstants {
 
                 try{
 
-                        if (file == null || file.isEmpty())
+                        if (file == null || file.length()==0)
                                 parser = new ADQLParser(System.in);
                         else if (file.matches(urlRegex))
                                 parser = new ADQLParser((new java.net.URL(file)).openStream());
diff --git a/src/adql/parser/adqlGrammar.jj b/src/adql/parser/adqlGrammar.jj
index 25f56573ebd38cdb7bb9ba7d1f80ab760a9fc681..83ff39080bbb3ea2dbb28f499520aef3a96aaaa2 100644
--- a/src/adql/parser/adqlGrammar.jj
+++ b/src/adql/parser/adqlGrammar.jj
@@ -433,7 +433,7 @@ public class ADQLParser {
 
 		try{
 
-			if (file == null || file.isEmpty())
+			if (file == null || file.length()==0)
 				parser = new ADQLParser(System.in);
 			else if (file.matches(urlRegex))
 				parser = new ADQLParser((new java.net.URL(file)).openStream());