Add support of Class.isInterface()

tests/should_check_if_class_is_interface.rs

@@ -0,0 +1,10 @@
+mod utils;
+use utils::get_int;
+use vm::vm::VM;
+
+#[test]
+fn should_check_if_class_is_interface() {
+    let last_frame_value =
+        VM::run("samples.reflection.trivial.classisinterface.ClassIsInterfaceExample").unwrap();
+    assert_eq!(1, get_int(last_frame_value))
+}

tests/test_data/ClassIsInterfaceExample.java

@@ -0,0 +1,18 @@
+package samples.reflection.trivial.classisinterface;
+
+import java.lang.annotation.ElementType;
+import java.util.AbstractMap;
+import java.util.HashMap;
+
+public class ClassIsInterfaceExample {
+    public static void main(String[] args) {
+        boolean runnableIsInterface = Runnable.class.isInterface();
+        boolean hashMapIsInterface = HashMap.class.isInterface();
+        boolean abstractMapIsInterface = AbstractMap.class.isInterface();
+        boolean elementTypeIsInterface = ElementType.class.isInterface();
+
+        int result = runnableIsInterface && !hashMapIsInterface && !abstractMapIsInterface && !elementTypeIsInterface
+                ? 1
+                : 0;
+    }
+}

vm/src/execution_engine/system_native_table.rs

@@ -3,7 +3,7 @@ use crate::execution_engine::system_native_table::NativeMethod::{Basic, WithStac
 use crate::helper::i64_to_vec;
 use crate::stack::stack_frame::StackFrames;
 use crate::system_native::class::{
-    get_modifiers_wrp, get_primitive_class_wrp, is_array_wrp, is_primitive_wrp,
+    get_modifiers_wrp, get_primitive_class_wrp, is_array_wrp, is_interface_wrp, is_primitive_wrp,
 };
 use crate::system_native::file_descriptor::file_descriptor_close0_wrp;
 use crate::system_native::file_output_stream::{
@@ -73,6 +73,7 @@ static SYSTEM_NATIVE_TABLE: Lazy<HashMap<&'static str, NativeMethod>> = Lazy::ne
     );
     table.insert("java/lang/Class:isPrimitive:()Z", Basic(is_primitive_wrp));
     table.insert("java/lang/Class:isArray:()Z", Basic(is_array_wrp));
+    table.insert("java/lang/Class:isInterface:()Z", Basic(is_interface_wrp));
     table.insert(
         "jdk/internal/misc/Unsafe:registerNatives:()V",
         Basic(void_stub as BasicNativeMethod),

vm/src/system_native/class.rs

@@ -105,3 +105,12 @@ fn is_array(reference: i32) -> bool {
         name.starts_with('[')
     })
 }
+
+pub(crate) fn is_interface_wrp(args: &[i32]) -> crate::error::Result<Vec<i32>> {
+    let interface = is_interface(args[0])?;
+
+    Ok(vec![interface as i32])
+}
+fn is_interface(reference: i32) -> crate::error::Result<bool> {
+    Ok((get_modifiers(reference)? as u16 & INTERFACE) != 0)
+}