From 1b4630f5898cc220fc5c93ebaa5226bbedcad96a Mon Sep 17 00:00:00 2001
From: arimu1 <19286898+arimu1@users.noreply.github.com>
Date: Sat, 22 Aug 2026 11:22:17 +0700
Subject: [PATCH] fixes SerialVersionUID for static inner classes.  Issue #517

---
 src/main/javassist/SerialVersionUID.java | 4 +++-
 src/test/javassist/JvstTest.java         | 6 ++++++
 src/test/test1/SerialVUIDOuter.java      | 7 +++++++
 3 files changed, 16 insertions(+), 1 deletion(-)
 create mode 100644 src/test/test1/SerialVUIDOuter.java

diff --git a/src/main/javassist/SerialVersionUID.java b/src/main/javassist/SerialVersionUID.java
index ebb18bfa..24dad307 100644
--- a/src/main/javassist/SerialVersionUID.java
+++ b/src/main/javassist/SerialVersionUID.java
@@ -93,7 +93,9 @@ public static long calculateDefault(CtClass clazz)
             CtMethod[] methods = clazz.getDeclaredMethods();
 
             // class modifiers.
-            int classMods = clazz.getModifiers();
+            int classMods = clazz.getModifiers()
+                           & (Modifier.PUBLIC | Modifier.FINAL
+                              | Modifier.INTERFACE | Modifier.ABSTRACT);
             if ((classMods & Modifier.INTERFACE) != 0)
                 if (methods.length > 0)
                     classMods = classMods | Modifier.ABSTRACT;
diff --git a/src/test/javassist/JvstTest.java b/src/test/javassist/JvstTest.java
index af11a726..da21f983 100644
--- a/src/test/javassist/JvstTest.java
+++ b/src/test/javassist/JvstTest.java
@@ -836,6 +836,7 @@ public void testCast() throws Exception {
     }
 
     static final long svUID = 6006955401253799668L;
+    static final long svUIDStaticInner = -5933347829989567997L;
 
     public void testSerialVUID() throws Exception {
         CtClass cc = sloader.get("test1.MySerializableClass");
@@ -844,6 +845,11 @@ public void testSerialVUID() throws Exception {
         cc.writeFile();
     }
 
+    public void testSerialVUIDStaticInner() throws Exception {
+        CtClass cc = sloader.get("test1.SerialVUIDOuter$Inner");
+        assertEquals(svUIDStaticInner, SerialVersionUID.calculateDefault(cc));
+    }
+
     public void testInvokeInt() throws Exception {
         CtClass cc = sloader.get("test1.InvokeInt");
         CtMethod m1 = cc.getDeclaredMethod("check");
diff --git a/src/test/test1/SerialVUIDOuter.java b/src/test/test1/SerialVUIDOuter.java
new file mode 100644
index 00000000..fbe99af0
--- /dev/null
+++ b/src/test/test1/SerialVUIDOuter.java
@@ -0,0 +1,7 @@
+package test1;
+
+import java.io.Serializable;
+
+public class SerialVUIDOuter {
+    public static class Inner implements Serializable { }
+}