use isNull

git-svn-id: https://svn.code.sf.net/p/jackcess/code/jackcess/branches/exprs@1075 f203690c-595d-4dc9-a70b-905162fa7fd2

2 files changed, 7 insertions, 4 deletions

diff --git a/src/main/java/com/healthmarketscience/jackcess/impl/expr/BuiltinOperators.java b/src/main/java/com/healthmarketscience/jackcess/impl/expr/BuiltinOperators.java
index 322fb7e..c295208 100644
--- a/src/main/java/com/healthmarketscience/jackcess/impl/expr/BuiltinOperators.java
+++ b/src/main/java/com/healthmarketscience/jackcess/impl/expr/BuiltinOperators.java
@@ -36,6 +36,9 @@ public class BuiltinOperators
   private static final String DIV_BY_ZERO = "/ by zero";
 
   public static final Value NULL_VAL = new BaseValue() {
+    @Override public boolean isNull() {
+      return true;
+    }
     public Type getType() {
       return Type.NULL;
     }
@@ -488,11 +491,11 @@ public class BuiltinOperators
   }
 
   public static Value isNull(Value param1) {
-    return toValue(param1.getType() == Value.Type.NULL);
+    return toValue(param1.isNull());
   }
 
   public static Value isNotNull(Value param1) {
-    return toValue(param1.getType() == Value.Type.NULL);
+    return toValue(!param1.isNull());
   }
 
   public static Value like(Value param1, Pattern pattern) {
diff --git a/src/main/java/com/healthmarketscience/jackcess/impl/expr/Expressionator.java b/src/main/java/com/healthmarketscience/jackcess/impl/expr/Expressionator.java
index d1d5968..5a9686f 100644
--- a/src/main/java/com/healthmarketscience/jackcess/impl/expr/Expressionator.java
+++ b/src/main/java/com/healthmarketscience/jackcess/impl/expr/Expressionator.java
@@ -1319,7 +1319,7 @@ public class Expressionator
     public Object evalDefault() {
       Value val = eval(null);
 
-      if(val.getType() == Value.Type.NULL) {
+      if(val.isNull()) {
         return null;
       }
 
@@ -1331,7 +1331,7 @@ public class Expressionator
     public Boolean evalCondition(RowContext ctx) {
       Value val = eval(ctx);
 
-      if(val.getType() == Value.Type.NULL) {
+      if(val.isNull()) {
         return null;
       }