java/File: add non-static GetAbsolutePath() overload

src/java/File.cxx

@@ -54,7 +54,7 @@ Java::File::ToAbsolutePath(JNIEnv *env, jobject _file) noexcept
 
 	LocalObject file(env, _file);
 
-	const jstring path = getAbsolutePath(env, file);
+	const jstring path = GetAbsolutePath(env, file);
 	if (DiscardException(env) || path == nullptr)
 		return nullptr;
 

src/java/File.hxx

@@ -31,6 +31,7 @@
 #define JAVA_FILE_HXX
 
 #include "Object.hxx"
+#include "String.hxx"
 
 #include <jni.h>
 
@@ -51,11 +52,19 @@ public:
 	static void Initialise(JNIEnv *env) noexcept;
 
 	gcc_nonnull_all
-	static jstring getAbsolutePath(JNIEnv *env, jobject file) noexcept {
+	static jstring GetAbsolutePath(JNIEnv *env, jobject file) noexcept {
 		return (jstring)env->CallObjectMethod(file,
 						      getAbsolutePath_method);
 	}
 
+	String GetAbsolutePath() const noexcept {
+		return {GetEnv(), GetAbsolutePath(GetEnv(), Get())};
+	}
+
+	String GetAbsolutePathChecked() const noexcept {
+		return *this ? GetAbsolutePath() : nullptr;
+	}
+
 	/**
 	 * Invoke File.getAbsolutePath() and release the
 	 * specified File reference.