rs4j 0.10.2

A small, automatic, efficient, and easy-to-use Rust to Java bridge.
Documentation 
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//! Utils for Java bindings

use jni::{
    objects::JValueGen,
    sys::{jlong, jobject},
    JNIEnv,
};

/// Convert a [`jlong`] to a `*mut T`
#[cfg(target_pointer_width = "32")]
pub unsafe fn jlong_to_pointer<T>(val: jlong) -> *mut T {
    (val as u32) as *mut T
}

/// Convert a [`jlong`] to a `*mut T`
#[cfg(target_pointer_width = "64")]
pub unsafe fn jlong_to_pointer<T>(val: jlong) -> *mut T {
    val as *mut T
}

/// Convert an object (`T`) to a [`jobject`]
#[allow(dead_code)]
pub fn object_to_jobject<T>(mut env: JNIEnv, obj: T, jcls: String) -> jobject {
    let jobj = env.alloc_object(jcls).unwrap();

    assert!(!jobj.is_null(), "object_to_jobject: AllocObject failed");

    let ret = Box::into_raw(Box::new(obj)) as jlong;
    let res = env.set_field(&jobj, "__pointer", "Long", JValueGen::Long(ret));

    if env.exception_check().unwrap() || res.is_err() {
        panic!("object_to_jobject: Can not set mNativeObj field: catch exception");
    }

    jobj.as_raw()
}