#112: impl Jvm::instance_into_raw_object and jvm::into_raw

Author: astonbitecode

rust/src/api/mod.rs

@@ -1233,6 +1233,30 @@ impl Jvm {
         }
     }
 
+    /// Consumes an `Instance` and returns its jobject. The returned jobject is a JNI local reference.
+    pub fn instance_into_raw_object(&self, instance: Instance) -> errors::Result<jobject> {
+        debug(&format!("Getting the raw jobject from instance of class {}", instance.borrow().class_name()));
+        // Call the getObjectMethod. This returns a localref
+        let object_instance = unsafe {
+            (opt_to_res(cache::get_jni_call_object_method())?)(
+                self.jni_env,
+                instance.jinstance,
+                cache::get_get_object_method()?,
+        )};
+
+        Self::do_return(
+            self.jni_env,
+            object_instance,
+        )
+    }
+
+    /// Consumes the `Jvm` and returns its `JNIEnv`
+    pub fn into_raw(self) -> *mut JNIEnv {
+        debug(&format!("Getting the raw JNIEnv from the Jvm"));
+
+        self.jni_env
+    }
+
     /// Returns the Rust representation of the provided instance, boxed
     pub fn to_rust_boxed<T>(&self, instance: Instance) -> errors::Result<Box<T>>
         where

rust/src/lib.rs

@@ -163,6 +163,7 @@ mod lib_unit_tests {
     use std::collections::HashMap;
     use std::convert::TryFrom;
     use std::path::MAIN_SEPARATOR;
+    use std::ptr::null_mut;
     use std::thread::JoinHandle;
     use std::{thread, time};
 
@@ -1302,4 +1303,22 @@ mod lib_unit_tests {
         assert!(jvm.check_equals(&null_instance, InvocationArg::try_from(Null::Integer)?)?);
         Ok(())
     }
+
+    #[test]
+    fn instance_into_raw_object() -> errors::Result<()> {
+        let jvm = create_tests_jvm()?;
+        let test_instance = jvm.create_instance("org.astonbitecode.j4rs.tests.MyTest", InvocationArg::empty())?;
+        let null_instance = jvm.invoke(&test_instance, "getNullInteger", InvocationArg::empty())?;
+        let jobj = jvm.instance_into_raw_object(null_instance)?;
+        assert!(jobj == null_mut());
+        Ok(())
+    }
+
+    #[test]
+    fn jvm_into_raw_object() -> errors::Result<()> {
+        let jvm = create_tests_jvm()?;
+        let jobj = jvm.into_raw();
+        assert!(jobj != null_mut());
+        Ok(())
+    }
 }