java_manager/
local.rs

1//! Functions for accessing Java from the local environment.
2
3use crate::JavaInfo;
4use std::env;
5
6/// Returns a `JavaInfo` for the Java installation pointed to by the `JAVA_HOME`
7/// environment variable, if set and valid.
8///
9/// This function reads the `JAVA_HOME` variable, treats it as a path, and attempts
10/// to create a `JavaInfo` from it. If the variable is not set or if the resulting
11/// `JavaInfo` cannot be created (e.g., the path does not contain a valid Java),
12/// `None` is returned.
13///
14/// # Examples
15///
16/// ```no_run
17/// use java_manager::java_home;
18///
19/// if let Some(java) = java_home() {
20///     println!("JAVA_HOME points to Java version {}", java.version);
21/// } else {
22///     println!("JAVA_HOME is not set or invalid");
23/// }
24/// ```
25pub fn java_home() -> Option<JavaInfo> {
26    env::var("JAVA_HOME")
27        .ok()
28        .and_then(|path| JavaInfo::new(path).ok())
29}
30
31#[cfg(test)]
32mod tests {
33    #[test]
34    fn test_java_home_not_set() {
35        let previous = std::env::var_os("JAVA_HOME");
36        // SAFETY: single-threaded test, no other code depends on JAVA_HOME
37        unsafe {
38            std::env::remove_var("JAVA_HOME");
39        }
40        let result = super::java_home();
41        assert!(result.is_none());
42        if let Some(val) = previous {
43            // SAFETY: restoring original value
44            unsafe {
45                std::env::set_var("JAVA_HOME", &val);
46            }
47        }
48    }
49
50    #[test]
51    fn test_java_home_invalid_path() {
52        let previous = std::env::var_os("JAVA_HOME");
53        // SAFETY: single-threaded test
54        unsafe {
55            std::env::set_var("JAVA_HOME", "/nonexistent/java/home");
56        }
57        let result = super::java_home();
58        assert!(result.is_none());
59        if let Some(val) = previous {
60            unsafe {
61                std::env::set_var("JAVA_HOME", &val);
62            }
63        } else {
64            unsafe {
65                std::env::remove_var("JAVA_HOME");
66            }
67        }
68    }
69}
java_manager/local.rs

java_manager/
local.rs
