From d4d309f3c02baae7f500bc201ce8b9ce2d6da40c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E9=99=88=E4=BA=9A=E4=B8=9C?= <yadong.cyd@alibaba-inc.com>
Date: Fri, 3 Nov 2023 14:14:16 +0800
Subject: [PATCH 1/2] fix and ut

---
 .../src/main/java/io/fury/codegen/Expression.java     |  8 ++++++--
 .../src/test/java/io/fury/codegen/ExpressionTest.java | 11 +++++++++++
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/java/fury-core/src/main/java/io/fury/codegen/Expression.java b/java/fury-core/src/main/java/io/fury/codegen/Expression.java
index 90c300386f..b7e2ecddca 100644
--- a/java/fury-core/src/main/java/io/fury/codegen/Expression.java
+++ b/java/fury-core/src/main/java/io/fury/codegen/Expression.java
@@ -182,12 +182,16 @@ public ExprCode doGenCode(CodegenContext ctx) {
           hasCode = true;
         }
       }
-      ExprCode lastExprCode = last.genCode(ctx);
       String code = codeBuilder.toString();
       if (!hasCode) {
         code = null;
       }
-      return new ExprCode(code, lastExprCode.isNull(), lastExprCode.value());
+      if (code != null) {
+        ExprCode lastExprCode = last.genCode(ctx);
+        return new ExprCode(code, lastExprCode.isNull(), lastExprCode.value());
+      } else {
+        return new ExprCode(code);
+      }
     }
 
     @Override
diff --git a/java/fury-core/src/test/java/io/fury/codegen/ExpressionTest.java b/java/fury-core/src/test/java/io/fury/codegen/ExpressionTest.java
index 72fdb4756c..730c66dff0 100644
--- a/java/fury-core/src/test/java/io/fury/codegen/ExpressionTest.java
+++ b/java/fury-core/src/test/java/io/fury/codegen/ExpressionTest.java
@@ -17,7 +17,9 @@
 package io.fury.codegen;
 
 import static io.fury.type.TypeUtils.PRIMITIVE_SHORT_TYPE;
+import static org.testng.Assert.assertNull;
 
+import io.fury.codegen.Expression.ListExpression;
 import io.fury.codegen.Expression.Literal;
 import io.fury.codegen.Expression.Reference;
 import io.fury.codegen.Expression.Return;
@@ -64,4 +66,13 @@ public void testIfExpression() {
       Assert.assertEquals(code, expected);
     }
   }
+
+  @Test
+  public void testListExpression() {
+    {
+      ListExpression exp = new ListExpression();
+      String code = exp.genCode(new CodegenContext()).code();
+      assertNull(code);
+    }
+  }
 }

From c53f7b8759541b546b3a2ed6b0b8a0b4b989f88d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E9=99=88=E4=BA=9A=E4=B8=9C?= <yadong.cyd@alibaba-inc.com>
Date: Fri, 3 Nov 2023 15:18:28 +0800
Subject: [PATCH 2/2] change

---
 .../src/main/java/io/fury/codegen/Expression.java    | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/java/fury-core/src/main/java/io/fury/codegen/Expression.java b/java/fury-core/src/main/java/io/fury/codegen/Expression.java
index b7e2ecddca..f2ca150d16 100644
--- a/java/fury-core/src/main/java/io/fury/codegen/Expression.java
+++ b/java/fury-core/src/main/java/io/fury/codegen/Expression.java
@@ -172,6 +172,10 @@ public TypeToken<?> type() {
 
     @Override
     public ExprCode doGenCode(CodegenContext ctx) {
+      if (last == null) {
+        return new ExprCode(null, null, null);
+      }
+
       StringBuilder codeBuilder = new StringBuilder();
       boolean hasCode = false;
       for (Expression expr : expressions) {
@@ -182,16 +186,12 @@ public ExprCode doGenCode(CodegenContext ctx) {
           hasCode = true;
         }
       }
+      ExprCode lastExprCode = last.genCode(ctx);
       String code = codeBuilder.toString();
       if (!hasCode) {
         code = null;
       }
-      if (code != null) {
-        ExprCode lastExprCode = last.genCode(ctx);
-        return new ExprCode(code, lastExprCode.isNull(), lastExprCode.value());
-      } else {
-        return new ExprCode(code);
-      }
+      return new ExprCode(code, lastExprCode.isNull(), lastExprCode.value());
     }
 
     @Override