[아이템 66] 네이티브 메서드는 신중히 사용하라

- Close java-squid#68

Author: david215

chapter09/item66/README.md

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+# Item 66: Use native methods judiciously
+
+## Key Points
+- It is rarely advisable to use native methods.
+    - Use the [Java process API](https://docs.oracle.com/en/java/javase/14/docs/api/java.base/java/lang/Process.html)
+      to access OS processes and platform-specific facilities.
+    - Native methods:
+        - are not *safe*.
+        - are less portable.
+        - are harder to debug.
+        - can *decrease* performance if not used correctly.
+        - requires tedious "glue code".
+- But correct usage *can* provide improved performance, e.g. using native
+  libraries like GMP.
+