NativeScript · edusperoni · Aug 15, 2026
diff --git a/test-app/app/src/main/assets/app/tests/testsForRuntimeBindingGenerator.js b/test-app/app/src/main/assets/app/tests/testsForRuntimeBindingGenerator.js
@@ -109,9 +109,9 @@ describe("Tests for runtime binding generator", function () {
 
         var interfaces = clazz.getInterfaces();
 
-        var expectedInterfaces = ["java.util.jar.Pack200$Packer", "java.util.Formattable", "java.util.Observer", "java.util.jar.Pack200$Unpacker", "com.tns.NativeScriptHashCodeProvider"];
+        var expectedInterfaces = ["java.util.jar.Pack200$Packer", "java.util.Formattable", "java.util.Observer", "java.util.jar.Pack200$Unpacker", "com.tns.NativeScriptHashCodeProvider", "com.tns.NativeScriptRuntimeBound"];
 
-        expect(interfaces.length).toBe(5);
+        expect(interfaces.length).toBe(6);
 
         for(var i = 0; i < interfaces.length; i++) {
             var interfaceName = interfaces[i].getName().toString();
@@ -168,9 +168,9 @@ describe("Tests for runtime binding generator", function () {
 
             var interfaces = clazz.getInterfaces();
 
-            var expectedInterfaces = ["java.util.jar.Pack200$Packer", "java.util.Formattable", "java.util.Observer", "java.util.jar.Pack200$Unpacker", "com.tns.NativeScriptHashCodeProvider"];
+            var expectedInterfaces = ["java.util.jar.Pack200$Packer", "java.util.Formattable", "java.util.Observer", "java.util.jar.Pack200$Unpacker", "com.tns.NativeScriptHashCodeProvider", "com.tns.NativeScriptRuntimeBound"];
 
-            expect(interfaces.length).toBe(5);
+            expect(interfaces.length).toBe(6);
 
             for(var i = 0; i < interfaces.length; i++) {
                 var interfaceName = interfaces[i].getName().toString();

diff --git a/...ic-binding-generator/src/main/java/org/nativescript/staticbindinggenerator/Generator.java b/...ic-binding-generator/src/main/java/org/nativescript/staticbindinggenerator/Generator.java
@@ -448,6 +448,8 @@ private void writeFieldsToWriter(Writer writer, JavaClass clazz) {
             String normalizedClassName = BcelNamingUtil.resolveClassName(clazz.getClassName());
             fieldsWriter.writeStaticThizField(normalizedClassName);
         }
+
+        fieldsWriter.writeRuntimeIdField();
     }
 
     private void writeConstructorsToWriter(Writer writer, JavaClass clazz, DataRow dataRow, String generatedClassName, GenericHierarchyView genericHierarchyView) {
@@ -523,6 +525,7 @@ private void writeMethodsToWriter(Writer writer, GenericHierarchyView genericHie
 
         methodsWriter.writeInternalRuntimeHashCodeMethod();
         methodsWriter.writeInternalRuntimeEqualsMethod();
+        methodsWriter.writeInternalRuntimeIdAccessorMethods();
     }
 
     /**

diff --git a/...rc/main/java/org/nativescript/staticbindinggenerator/generating/writing/FieldsWriter.java b/...rc/main/java/org/nativescript/staticbindinggenerator/generating/writing/FieldsWriter.java
@@ -2,4 +2,5 @@
 
 public interface FieldsWriter extends JavaCodeWriter {
     void writeStaticThizField(String className);
+    void writeRuntimeIdField();
 }
diff --git a/...c/main/java/org/nativescript/staticbindinggenerator/generating/writing/MethodsWriter.java b/...c/main/java/org/nativescript/staticbindinggenerator/generating/writing/MethodsWriter.java
@@ -8,5 +8,6 @@ public interface MethodsWriter extends JavaCodeWriter {
     void writeGetInstanceMethod(String className);
     void writeInternalRuntimeEqualsMethod();
     void writeInternalRuntimeHashCodeMethod();
+    void writeInternalRuntimeIdAccessorMethods();
     void writeInternalServiceOnCreateMethod();
 }
diff --git a/...java/org/nativescript/staticbindinggenerator/generating/writing/impl/ClassWriterImpl.java b/...java/org/nativescript/staticbindinggenerator/generating/writing/impl/ClassWriterImpl.java
@@ -11,6 +11,7 @@ public class ClassWriterImpl implements ClassWriter {
     private static final String PUBLIC_CLASS_KEYWORD = "public class";
     private static final String JAVASCRIPT_IMPLEMENTATION_FILE_NAME_PATTERN = "@com.tns.JavaScriptImplementation(javaScriptFile = \"./%s\")";
     private static final String NATIVESCRIPT_HASHCODE_PROVIDER_INTERFACE_NAME = "com.tns.NativeScriptHashCodeProvider";
+    private static final String NATIVESCRIPT_RUNTIME_BOUND_INTERFACE_NAME = "com.tns.NativeScriptRuntimeBound";
     private static final String NOT_EXTENDING_ANY_CLASS_MESSAGE = "Not extending any class!";
 
     private final Writer writer;
@@ -42,6 +43,9 @@ public void writeBeginningOfChildClass(String className, String extendedClassNam
         writer.write(IMPLEMENTS_KEYWORD);
         writer.write(SPACE_LITERAL);
         writer.write(NATIVESCRIPT_HASHCODE_PROVIDER_INTERFACE_NAME);
+        writer.write(COMMA_LITERAL);
+        writer.write(SPACE_LITERAL);
+        writer.write(NATIVESCRIPT_RUNTIME_BOUND_INTERFACE_NAME);
 
         if (!isEmpty(implementedInterfacesNames) && !isEmpty(implementedInterfacesNames.get(0))) {
             writer.write(COMMA_LITERAL);

diff --git a/...ava/org/nativescript/staticbindinggenerator/generating/writing/impl/FieldsWriterImpl.java b/...ava/org/nativescript/staticbindinggenerator/generating/writing/impl/FieldsWriterImpl.java
@@ -7,13 +7,21 @@ public class FieldsWriterImpl implements FieldsWriter {
 
 
     private static final String THIZ_KEYWORD = "thiz";
+    private static final String RUNTIME_ID_FIELD_DECLARATION = "private int runtimeId__ns = com.tns.NativeScriptRuntimeBound.INVALID_RUNTIME_ID;";
 
     private final Writer writer;
 
     public FieldsWriterImpl(final Writer writer) {
         this.writer = writer;
     }
 
+    @Override
+    public void writeRuntimeIdField() {
+        writer.write(TABULATION_LITERAL);
+        writer.writeln(RUNTIME_ID_FIELD_DECLARATION);
+        writer.writeln();
+    }
+
     @Override
     public void writeStaticThizField(String className) {
         writer.write(TABULATION_LITERAL);

diff --git a/...va/org/nativescript/staticbindinggenerator/generating/writing/impl/MethodsWriterImpl.java b/...va/org/nativescript/staticbindinggenerator/generating/writing/impl/MethodsWriterImpl.java
@@ -47,6 +47,10 @@ public class MethodsWriterImpl implements MethodsWriter {
 
     private static final String INTERNAL_RUNTIME_EQUALS_METHOD_SIGNATURE = "public boolean equals__super(java.lang.Object other)";
     private static final String INTERNAL_RUNTIME_HASHCODE_METHOD_SIGNATURE = "public int hashCode__super()";
+    private static final String INTERNAL_RUNTIME_GET_RUNTIME_ID_METHOD_SIGNATURE = "public int getRuntimeId__ns()";
+    private static final String INTERNAL_RUNTIME_GET_RUNTIME_ID_RETURN_STATEMENT = "return runtimeId__ns;";
+    private static final String INTERNAL_RUNTIME_SET_RUNTIME_ID_METHOD_SIGNATURE = "public void setRuntimeId__ns(int runtimeId)";
+    private static final String INTERNAL_RUNTIME_SET_RUNTIME_ID_ASSIGNMENT = "runtimeId__ns = runtimeId;";
     private static final String INTERNAL_SERVICES_ONCREATE_METHOD_SIGNATURE = "public void " + ON_CREATE_METHOD_NAME + "()";
 
     private static final String RETURN_KEYWORD = "return";
@@ -369,7 +373,7 @@ private void writeCallJsMethodExceptionsSuppressBlockClosingIfNecessary(Type ret
         if (shouldSuppressCallJsMethodExceptions) {
             writer.write(CLOSING_CURLY_BRACKET_LITERAL);
             writer.write(GENERIC_CATCH_BLOCK_BEGINNING);
-            writer.writeln("\t\t\tcom.tns.Runtime.passSuppressedExceptionToJs(throwable, \"" + methodName + "\");");
+            writer.writeln("\t\t\tcom.tns.Runtime.passSuppressedExceptionToJs(this, throwable, \"" + methodName + "\");");
             writer.writeln(ANDROID_LOG_METHOD_CALL_STATEMENT);
 
             if (!returnType.equals(Type.VOID)) {
@@ -398,6 +402,12 @@ public void writeInternalRuntimeHashCodeMethod() {
         writeInternalRuntimeMethod(INTERNAL_RUNTIME_HASHCODE_METHOD_SIGNATURE, INTERNAL_RUNTIME_HASHCODE_METHOD_RETURN_STATEMENT);
     }
 
+    @Override
+    public void writeInternalRuntimeIdAccessorMethods() {
+        writeInternalRuntimeMethod(INTERNAL_RUNTIME_GET_RUNTIME_ID_METHOD_SIGNATURE, INTERNAL_RUNTIME_GET_RUNTIME_ID_RETURN_STATEMENT);
+        writeInternalRuntimeMethod(INTERNAL_RUNTIME_SET_RUNTIME_ID_METHOD_SIGNATURE, INTERNAL_RUNTIME_SET_RUNTIME_ID_ASSIGNMENT);
+    }
+
     private void writeInternalRuntimeMethod(String signature, String returnStatement) {
         writer.write(signature);
         writer.write(OPENING_CURLY_BRACKET_LITERAL);

diff --git a/test-app/build-tools/static-binding-generator/src/test/java/android/util/Log.java b/test-app/build-tools/static-binding-generator/src/test/java/android/util/Log.java
@@ -0,0 +1,11 @@
+package android.util;
+
+/**
+ * Stub for compiling generated bindings in tests: the exception-suppressing
+ * variant emits a call to android.util.Log, which is not on the test classpath.
+ */
+public class Log {
+    public static int w(String tag, String msg) {
+        return 0;
+    }
+}
diff --git a/.../build-tools/static-binding-generator/src/test/java/com/tns/NativeScriptRuntimeBound.java b/.../build-tools/static-binding-generator/src/test/java/com/tns/NativeScriptRuntimeBound.java
@@ -0,0 +1,9 @@
+package com.tns;
+
+public interface NativeScriptRuntimeBound {
+    int INVALID_RUNTIME_ID = -1;
+
+    int getRuntimeId__ns();
+
+    void setRuntimeId__ns(int runtimeId);
+}
diff --git a/test-app/build-tools/static-binding-generator/src/test/java/com/tns/Runtime.java b/test-app/build-tools/static-binding-generator/src/test/java/com/tns/Runtime.java
@@ -5,4 +5,5 @@ public static void initInstance(Object instance) {}
     public static Object callJSMethod(Object javaObject, String methodName, Class<?> retType, Object... args) {
         return null;
     }
+    public static void passSuppressedExceptionToJs(Object instance, Throwable ex, String methodName) {}
 }
diff --git a/...g-generator/src/test/java/org/nativescript/staticbindinggenerator/test/GeneratorTest.java b/...g-generator/src/test/java/org/nativescript/staticbindinggenerator/test/GeneratorTest.java
@@ -53,7 +53,50 @@ public void testCanCompileBinding() throws Exception {
         Class<?> helloClass = InMemoryJavaCompiler.compile(binding.getClassname(), sourceCode.toString(), options);
 
         Assert.assertNotNull(helloClass);
-        Assert.assertEquals(3, helloClass.getDeclaredMethods().length);
+        Assert.assertEquals(5, helloClass.getDeclaredMethods().length);
+    }
+
+    @Test
+    public void testCanCompileBindingWithSuppressedCallJsMethodExceptions() throws Exception {
+        List<String> lines = Utils.getDataRowsFromResource("datarow-named-extend.txt");
+        DataRow dataRow = new DataRow(lines.get(0));
+
+        File outputDir = null;
+        List<DataRow> libs = new ArrayList<>();
+        Generator generator = new Generator(outputDir, libs, true);
+        Binding binding = generator.generateBinding(dataRow);
+        Assert.assertNotNull(binding);
+
+        String sourceCode = binding.getContent();
+        Assert.assertTrue(sourceCode.contains("com.tns.Runtime.passSuppressedExceptionToJs(this,"));
+
+        Iterable<String> options = new ArrayList<String>(Arrays.asList("-cp", dependenciesDir));
+        Class<?> helloClass = InMemoryJavaCompiler.compile(binding.getClassname(), sourceCode, options);
+
+        Assert.assertNotNull(helloClass);
+    }
+
+    @Test
+    public void testBindingCarriesItsOwningRuntimeId() throws Exception {
+        List<String> lines = Utils.getDataRowsFromResource("datarow-named-extend.txt");
+        DataRow dataRow = new DataRow(lines.get(0));
+
+        File outputDir = null;
+        List<DataRow> libs = new ArrayList<>();
+        Generator generator = new Generator(outputDir, libs);
+        Binding binding = generator.generateBinding(dataRow);
+        Assert.assertNotNull(binding);
+
+        Iterable<String> options = new ArrayList<String>(Arrays.asList("-cp", dependenciesDir));
+        Class<?> boundClass = InMemoryJavaCompiler.compile(binding.getClassname(), binding.getContent(), options);
+
+        Assert.assertTrue(com.tns.NativeScriptRuntimeBound.class.isAssignableFrom(boundClass));
+
+        com.tns.NativeScriptRuntimeBound instance = (com.tns.NativeScriptRuntimeBound) boundClass.newInstance();
+        Assert.assertEquals(com.tns.NativeScriptRuntimeBound.INVALID_RUNTIME_ID, instance.getRuntimeId__ns());
+
+        instance.setRuntimeId__ns(7);
+        Assert.assertEquals(7, instance.getRuntimeId__ns());
     }
 
     @Test
@@ -79,7 +122,7 @@ public void testCanCompileBindingOfInterfaceWithStaticInitializer() throws Excep
         Class<?> helloClass = InMemoryJavaCompiler.compile("com.tns.gen.com.example.MyInterface", sourceCode.toString(), options);
 
         Assert.assertNotNull(helloClass);
-        Assert.assertEquals(3, helloClass.getDeclaredMethods().length);  // 3 methods (includes 'hashCode__super' and 'equals__super')
+        Assert.assertEquals(5, helloClass.getDeclaredMethods().length);  // 5 methods (includes 'hashCode__super', 'equals__super', 'getRuntimeId__ns' and 'setRuntimeId__ns')
     }
 
     @Test
@@ -100,7 +143,7 @@ public void testCanCompileBindingClassImplementingMultipleInterfaces() throws Ex
         Class<?> ComplexClass = InMemoryJavaCompiler.compile(binding.getClassname(), sourceCode.toString(), options);
 
         Assert.assertNotNull(ComplexClass);
-        Assert.assertEquals(3, ComplexClass.getInterfaces().length); // 2 + 1 (hashcodeprovider)
+        Assert.assertEquals(4, ComplexClass.getInterfaces().length); // 2 + hashcodeprovider + runtimebound
     }
 
     @Test
@@ -127,7 +170,7 @@ public void testCanCompileBindingClassExtendingAnExtendedClassWithMethodsWithThe
         Class<?> ComplexClass = InMemoryJavaCompiler.compile(binding.getClassname(), sourceCode.toString(), options);
 
         Assert.assertNotNull(ComplexClass);
-        Assert.assertEquals(4, ComplexClass.getDeclaredMethods().length); // 1 + constructor + (equals + hashcode)
+        Assert.assertEquals(6, ComplexClass.getDeclaredMethods().length); // 1 + constructor + (equals + hashcode) + (getRuntimeId__ns + setRuntimeId__ns)
     }
 
     @Test

diff --git a/test-app/runtime-binding-generator/src/main/java/com/tns/NativeScriptRuntimeBound.java b/test-app/runtime-binding-generator/src/main/java/com/tns/NativeScriptRuntimeBound.java
@@ -0,0 +1,24 @@
+package com.tns;
+
+/**
+ * Implemented by generated binding classes so that a Java-&gt;JS call can be routed
+ * to the runtime that created the instance rather than inferred from the calling
+ * thread.
+ *
+ * The runtime id is written once, by the runtime that registers the instance, and
+ * is never reassigned: an instance may later be wrapped by other runtimes (each
+ * keeps its own object-id map), but only the creating runtime holds the JS
+ * implementation the generated overrides dispatch to.
+ */
+public interface NativeScriptRuntimeBound {
+    /**
+     * Not 0: that is a real runtime id (the main runtime's), and JsV8InspectorClient
+     * hard-codes it as such. Implementations must therefore seed the backing field
+     * rather than rely on its natural zero default.
+     */
+    int INVALID_RUNTIME_ID = -1;
+
+    int getRuntimeId__ns();
+
+    void setRuntimeId__ns(int runtimeId);
+}
diff --git a/test-app/runtime-binding-generator/src/main/java/com/tns/bindings/Dump.java b/test-app/runtime-binding-generator/src/main/java/com/tns/bindings/Dump.java
@@ -23,6 +23,7 @@ public class Dump {
     static final String runtimeClass = LCOM_TNS_RUNTIME;
     static final String callJSMethodName = "callJSMethod";
     static final String initInstanceMethodName = "initInstance";
+    static final String RUNTIME_ID_FIELD_NAME = "runtimeId__ns";
 
     static final StringBuffer methodDescriptorBuilder = new StringBuffer();
 
@@ -449,6 +450,8 @@ private void generateCtor(ClassVisitor cv, ClassDescriptor classTo, MethodDescri
             mv.visitMethodInsn(org.ow2.asmdex.Opcodes.INSN_INVOKE_DIRECT_RANGE, objectClass, "<init>", ctorSignature, args);
         }
 
+        generateRuntimeIdInitialization(mv, thisRegister, tnsClassSignature);
+
         if (!isApplicationClass(classTo)) {
             generateInitializedBlock(mv, thisRegister, classSignature, tnsClassSignature);
         }
@@ -473,6 +476,20 @@ private void generateCtorOverridenBlock(MethodVisitor mv, int thisRegister, Meth
                            { 3, 1, 2, 0 }); //invoke callJSMethod(this, "init", true, params)
     }
 
+    /*
+     * Seeds runtimeId__ns with NativeScriptRuntimeBound.INVALID_RUNTIME_ID, which a
+     * dex field's zero default does not give us - 0 is the main runtime's id. Runs
+     * as early as a constructor can touch the instance, which still leaves the
+     * superclass constructor above it reading 0; a proxied method called from there
+     * resolves to the main runtime, finds no object id registered, and reports that
+     * instead. It cannot run earlier: the verifier rejects field access on an
+     * uninitialized reference.
+     */
+    private void generateRuntimeIdInitialization(MethodVisitor mv, int thisRegister, String tnsClassSignature) {
+        mv.visitVarInsn(org.ow2.asmdex.Opcodes.INSN_CONST_4, thisRegister - 1, -1);
+        mv.visitFieldInsn(org.ow2.asmdex.Opcodes.INSN_IPUT, tnsClassSignature, RUNTIME_ID_FIELD_NAME, "I", thisRegister - 1, thisRegister);
+    }
+
     private void generateInitializedBlock(MethodVisitor mv, int thisRegister, String classSignature, String tnsClassSignature) {
         mv.visitFieldInsn(org.ow2.asmdex.Opcodes.INSN_IGET_BOOLEAN, tnsClassSignature, "__initialized", "Z", thisRegister - 2, thisRegister); //put __initialized in local var 1
         Label label = new Label();
@@ -493,6 +510,28 @@ private void generateMethods(ClassVisitor cv, ClassDescriptor classTo, MethodDes
 
         generateEqualsSuper(cv);
         generateHashCodeSuper(cv);
+        generateGetRuntimeId(cv, tnsClassSignature);
+        generateSetRuntimeId(cv, tnsClassSignature);
+    }
+
+    // 2 registers, 1 parameter: 'this' takes the last one, v0 is left as scratch
+    private void generateGetRuntimeId(ClassVisitor cv, String tnsClassSignature) {
+        MethodVisitor mv = cv.visitMethod(org.ow2.asmdex.Opcodes.ACC_PUBLIC, "getRuntimeId__ns", "I", null, null);
+        mv.visitCode();
+        mv.visitMaxs(2, 0);
+        mv.visitFieldInsn(org.ow2.asmdex.Opcodes.INSN_IGET, tnsClassSignature, RUNTIME_ID_FIELD_NAME, "I", 0, 1);
+        mv.visitIntInsn(org.ow2.asmdex.Opcodes.INSN_RETURN, 0);
+        mv.visitEnd();
+    }
+
+    // 2 registers, 2 parameters: v0 is 'this' and v1 the id, leaving no scratch
+    private void generateSetRuntimeId(ClassVisitor cv, String tnsClassSignature) {
+        MethodVisitor mv = cv.visitMethod(org.ow2.asmdex.Opcodes.ACC_PUBLIC, "setRuntimeId__ns", "VI", null, null);
+        mv.visitCode();
+        mv.visitMaxs(2, 0);
+        mv.visitFieldInsn(org.ow2.asmdex.Opcodes.INSN_IPUT, tnsClassSignature, RUNTIME_ID_FIELD_NAME, "I", 1, 0);
+        mv.visitInsn(org.ow2.asmdex.Opcodes.INSN_RETURN_VOID);
+        mv.visitEnd();
     }
 
     private void generateEqualsSuper(ClassVisitor cv) {
@@ -804,10 +843,14 @@ private void generateReturnFromObject(MethodVisitor mv, ClassDescriptor targetRe
     private void generateFields(ClassVisitor cv) {
         FieldVisitor fv = cv.visitField(org.ow2.asmdex.Opcodes.ACC_PRIVATE, "__initialized", "Z", null, null);
         fv.visitEnd();
+
+        // seeded per constructor, see generateRuntimeIdInitialization
+        fv = cv.visitField(org.ow2.asmdex.Opcodes.ACC_PRIVATE, RUNTIME_ID_FIELD_NAME, "I", null, null);
+        fv.visitEnd();
     }
 
-    static final String[] classImplentedInterfaces = new String[] { "Lcom/tns/NativeScriptHashCodeProvider;" };
-    static final String[] interfaceImplementedInterfaces = new String[] { "Lcom/tns/NativeScriptHashCodeProvider;", "" };
+    static final String[] classImplentedInterfaces = new String[] { "Lcom/tns/NativeScriptHashCodeProvider;", "Lcom/tns/NativeScriptRuntimeBound;" };
+    static final String[] interfaceImplementedInterfaces = new String[] { "Lcom/tns/NativeScriptHashCodeProvider;", "Lcom/tns/NativeScriptRuntimeBound;", "" };
 
     private ClassVisitor generateClass(ApplicationWriter aw, ClassDescriptor classTo, String classSignature, String tnsClassSignature, HashSet<ClassDescriptor> implementedInterfaces, AnnotationDescriptor[] annotations) {
         ClassVisitor cv;
@@ -817,7 +860,7 @@ private ClassVisitor generateClass(ApplicationWriter aw, ClassDescriptor classTo
         ArrayList<String> interfacesToImplement = new ArrayList(Arrays.asList(classImplentedInterfaces));
 
         if (classTo.isInterface()) {
-            interfaceImplementedInterfaces[1] = classSignature; //new String[] { "Lcom/tns/NativeScriptHashCodeProvider;", classSignature };
+            interfaceImplementedInterfaces[interfaceImplementedInterfaces.length - 1] = classSignature;
             for (String interfaceToImpl : interfaceImplementedInterfaces) {
                 if (!interfacesToImplement.contains(interfaceToImpl)) {
                     interfacesToImplement.add(interfaceToImpl);