Cannot Pass Vec as a Parameter to Java Function #122
Description
Hi!
Creating this ticket to track using Vec <-> List / ArrayList for function parameters.
Expectation: I can pass in a list of arguments (of any type) to a Java function via Duchess
Current: I can pass in a Vec<T> to a Rust function if it is a parameter for a Java Record. I cannot pass Vec<T> directly as parameters.
See code below for reproduction.
See compiler output for what I'm seeing for the two cases: test_with_string_array and test_with_string_list.
Java side:
import java.util.List;
public class KerenDemo {
public void test_with_string_array(String[] x) {
System.out.println(x);
}
public void test_with_string_list(List<String> x) {
System.out.println(x);
}
public void test_record_param_is_string_list(StringListRecord input) {
System.out.println(input.records());
}
}
import java.util.List;
public record StringListRecord(
List<String> records
) { }
Rust Side:
duchess::java_package! {
package demo;
class KerenDemo { * }
class StringListRecord { * }
}
#[derive(Clone, Debug, PartialEq, duchess::ToJava)]
#[java(demo.StringListRecord)]
pub struct StringListRecord {
pub records: Vec<String>,
}
pub struct DemoClient {
client: duchess::Global<demo::KerenDemo>,
}
impl RustKerenDemo {
pub fn new() -> Arc<Self> {
Arc::new(DemoClient { client: Self::build_client().unwrap() })
}
fn build_client() -> duchess::GlobalResult<Global<demo::KerenDemo>> {
duchess::Jvm::builder().launch_or_use_existing().unwrap();
metering::KerenDemo::new().global().execute()
}
pub fn does_not_work (self: Arc<Self>) {
tokio::task::spawn_blocking(move || {
duchess::Jvm::attach_thread_permanently().unwrap();
self.client
.test_with_string_list(vec!["Some signature".into()])
.execute()
.unwrap();
});
}
pub fn does_not_work_2 (self: Arc<Self>) {
tokio::task::spawn_blocking(move || {
duchess::Jvm::attach_thread_permanently().unwrap();
self.client
.test_with_string_array(vec![String::from("Some signature")])
.execute()
.unwrap();
});
}
pub fn this_works(self: Arc<Self>) {
let record = StringListRecord {
records: vec!["Some signature".into()],
};
tokio::task::spawn_blocking(move || {
duchess::Jvm::attach_thread_permanently().unwrap();
self.client
.test_record_param_is_string_list(&record)
.execute()
.unwrap();
});
}
}
Compiler output for the two functions above where it does not work:
--> src/lib.rs:125:41
|
125 | .test_with_string_array(vec![String::from("Some signature")])
| ---------------------- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `duchess::JvmOp` is not implemented for `Vec<std::string::String>`
| |
| required by a bound introduced by this call
|
= help: the following other types implement trait `duchess::JvmOp`:
bool
char
i8
i16
i32
i64
u16
f32
and 192 others
= note: required for `Vec<std::string::String>` to implement `duchess::IntoJava<Array<duchess::java::lang::String>>`
note: required by a bound in `ViewAsKerenDemoObj::<J, N>::test_with_string_array`
--> src/lib.rs:14:1
|
14 | / duchess::java_package! {
15 | | package demo;
16 | |
17 | | class KerenDemo { * }
18 | | class StringListRecord { * }
20 | | }
| |_^ required by this bound in `ViewAsKerenDemoObj::<J, N>::test_with_string_array`
= note: this error originates in the macro `duchess::java_package` (in Nightly builds, run with -Z macro-backtrace for more info)