feat: support AbstractTranslet packer

2026-09-21 22:50:42 +08:00 · 2025-11-20 00:36:25 +08:00
parent bd308fae10
commit 6b1a569be9
11 changed files with 219 additions and 1 deletions
@@ -0,0 +1,65 @@
+package com.reajason.javaweb.asm;
+
+import org.objectweb.asm.*;
+
+public class ClassSuperClassUtils {
+
+    public static byte[] addSuperClass(byte[] bytes, String superClassName) {
+        ClassReader cr = new ClassReader(bytes);
+        ClassWriter cw = new ClassWriter(cr, 0);
+        ClassVisitor cv = new AddSuperClassAdapter(cw, superClassName.replace('.', '/'));
+        cr.accept(cv, 0);
+        return cw.toByteArray();
+    }
+
+    static class AddSuperClassAdapter extends ClassVisitor {
+        private final String newSuperName;
+
+        public AddSuperClassAdapter(ClassVisitor cv, String newSuperName) {
+            super(Opcodes.ASM9, cv);
+            this.newSuperName = newSuperName;
+        }
+
+        @Override
+        public void visit(int version, int access, String name,
+                          String signature, String superName, String[] interfaces) {
+            if (!"java/lang/Object".equals(superName)) {
+                throw new IllegalStateException(String.format(
+                        "Cannot add superclass to class '%s': it already extends '%s'.", name, superName
+                ));
+            }
+            super.visit(version, access, name, signature, newSuperName, interfaces);
+        }
+
+        @Override
+        public MethodVisitor visitMethod(int access, String name, String descriptor,
+                                         String signature, String[] exceptions) {
+            MethodVisitor mv = super.visitMethod(access, name, descriptor, signature, exceptions);
+            if ("<init>".equals(name)) {
+                return new ChangeConstructorAdapter(mv, newSuperName);
+            }
+            return mv;
+        }
+    }
+
+    static class ChangeConstructorAdapter extends MethodVisitor {
+        private final String newSuperName;
+
+        public ChangeConstructorAdapter(MethodVisitor mv, String newSuperName) {
+            super(Opcodes.ASM9, mv);
+            this.newSuperName = newSuperName;
+        }
+
+        @Override
+        public void visitMethodInsn(int opcode, String owner, String name,
+                                    String descriptor, boolean isInterface) {
+            if (opcode == Opcodes.INVOKESPECIAL &&
+                    "java/lang/Object".equals(owner) &&
+                    "<init>".equals(name)) {
+                super.visitMethodInsn(opcode, newSuperName, name, descriptor, isInterface);
+            } else {
+                super.visitMethodInsn(opcode, owner, name, descriptor, isInterface);
+            }
+        }
+    }
+}
@@ -0,0 +1,37 @@
+package com.reajason.javaweb.asm;
+
+import net.bytebuddy.ByteBuddy;
+import org.junit.jupiter.api.Test;
+import org.objectweb.asm.ClassReader;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+/**
+ * @author ReaJason
+ * @since 2025/11/19
+ */
+class ClassSuperClassUtilsTest {
+    @Test
+    void test() {
+        String superClassName = "com.sun.org.apache.xalan.internal.xsltc.runtime.AbstractTranslet";
+        byte[] bytes = new ByteBuddy().redefine(EmptySuperClass.class).make().getBytes();
+        byte[] newBytes = ClassSuperClassUtils.addSuperClass(bytes, superClassName);
+        assertEquals("java/lang/Object", new ClassReader(bytes).getSuperName());
+        assertEquals(superClassName.replace(".", "/"), new ClassReader(newBytes).getSuperName());
+    }
+
+    @Test
+    void testException() {
+        String superClassName = "com.sun.org.apache.xalan.internal.xsltc.runtime.AbstractTranslet";
+        byte[] bytes = new ByteBuddy().redefine(SuperClass.class).make().getBytes();
+        assertThrows(IllegalStateException.class, () -> ClassSuperClassUtils.addSuperClass(bytes, superClassName));
+    }
+
+    class EmptySuperClass {
+
+    }
+
+    class SuperClass extends EmptySuperClass {
+    }
+}