diff --git a/jode/jode/expr/Expression.java b/jode/jode/expr/Expression.java
index 9312f0a..4feaaaf 100644
--- a/jode/jode/expr/Expression.java
+++ b/jode/jode/expr/Expression.java
@@ -23,6 +23,12 @@ import jode.GlobalOptions;
 import jode.decompiler.TabbedPrintWriter;
 import jode.flow.VariableSet;
 
+///#ifdef JDK12
+///import java.util.Set;
+///#else
+import jode.util.SimpleSet;
+///#endif
+
 public abstract class Expression {
     protected Type type;
 
@@ -226,6 +232,13 @@ public abstract class Expression {
     public void fillInGenSet(VariableSet in, VariableSet gen) {
     }
 
+///#ifdef JDK12
+///    public void fillDeclarables(Set used) {
+///#else
+    public void fillDeclarables(SimpleSet used) {
+///#endif
+    }
+
     public abstract void dumpExpression(TabbedPrintWriter writer) 
 	throws java.io.IOException;