Hi everyone,
I'm trying to initialize structure:

use jni::{AttachGuard, InitArgsBuilder, JNIVersion, JavaVM};

pub struct JEnv<'a> {
    jvm: JavaVM,
    pub jenv: AttachGuard<'a>,
}

impl<'a> JEnv<'a> {
    fn new(class_path: Vec<String>) -> Self {
        let jvm_args = InitArgsBuilder::new()
            .version(JNIVersion::V8)
            .option("-Xcheck:jni")
            .option(format!("-Djava.class.path={}", class_path.join(":")))
            .build()
            .unwrap();

        let ljvm = JavaVM::new(jvm_args).unwrap();
        let mut ljenv = ljvm.attach_current_thread().unwrap();

        Self {
            jvm: ljvm,
            jenv: ljenv,
        }
    }
}

but got compilation failed:

  --> rsjrs/src/jenv.rs:18:13
   |
18 |         let mut ljenv = ljvm.attach_current_thread().unwrap();
   |             ----^^^^^
   |             |
   |             help: remove this `mut`
   |
   = note: `#[warn(unused_mut)]` on by default

error[E0515]: cannot return value referencing local variable `ljvm`
  --> rsjrs/src/jenv.rs:20:9
   |
18 |           let mut ljenv = ljvm.attach_current_thread().unwrap();
   |                           ---- `ljvm` is borrowed here
19 |
20 | /         Self {
21 | |             jvm: ljvm,
22 | |             jenv: ljenv,
23 | |         }
   | |_________^ returns a value referencing data owned by the current function

error[E0505]: cannot move out of `ljvm` because it is borrowed
  --> rsjrs/src/jenv.rs:21:18
   |
8  |   impl<'a> JEnv<'a> {
   |        -- lifetime `'a` defined here
...
17 |           let ljvm = JavaVM::new(jvm_args).unwrap();
   |               ---- binding `ljvm` declared here
18 |           let mut ljenv = ljvm.attach_current_thread().unwrap();
   |                           ---- borrow of `ljvm` occurs here
19 |
20 | /         Self {
21 | |             jvm: ljvm,
   | |                  ^^^^ move out of `ljvm` occurs here
22 | |             jenv: ljenv,
23 | |         }
   | |_________- returning this value requires that `ljvm` is borrowed for `'a`

How can it be fixed? (I'm a novice in Rust)

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