make the localization related handles in NativeImageAgentJNIHandleSet lazy

Author: d-kozak

substratevm/src/com.oracle.svm.agent/src/com/oracle/svm/agent/BreakpointInterceptor.java

@@ -592,14 +592,14 @@ private static boolean getBundleImplJDK11OrLater(JNIEnvironment jni, Breakpoint
     }
 
     private static String readLocaleTag(JNIEnvironment jni, JNIObjectHandle locale) {
-        return fromJniString(jni, callObjectMethod(jni, locale, agent.handles().javaUtilLocaleToLanguageTag));
+        return fromJniString(jni, callObjectMethod(jni, locale, agent.handles().getJavaUtilLocaleToLanguageTag(jni)));
     }
 
     private static List<Pair<String, String>> extractBundleInfo(JNIEnvironment jni, JNIObjectHandle result) {
         List<Pair<String, String>> res = new ArrayList<>();
         JNIObjectHandle curr = result;
         while (!nullHandle().equal(curr)) {
-            JNIObjectHandle locale = callObjectMethod(jni, curr, agent.handles().javaUtilResourceBundleGetLocale);
+            JNIObjectHandle locale = callObjectMethod(jni, curr, agent.handles().getJavaUtilResourceBundleGetLocale(jni));
             if (clearException(jni)) {
                 return null;
             }
@@ -617,7 +617,7 @@ private static List<Pair<String, String>> extractBundleInfo(JNIEnvironment jni,
     }
 
     private static JNIObjectHandle getParent(JNIEnvironment jni, JNIObjectHandle curr) {
-        JNIObjectHandle parent = readObjectField(jni, curr, agent.handles().javaUtilResourceBundleParentField);
+        JNIObjectHandle parent = readObjectField(jni, curr, agent.handles().getJavaUtilResourceBundleParentField(jni));
         if (!clearException(jni)) {
             return parent;
         }

substratevm/src/com.oracle.svm.agent/src/com/oracle/svm/agent/NativeImageAgentJNIHandleSet.java

@@ -69,9 +69,9 @@ public class NativeImageAgentJNIHandleSet extends JNIHandleSet {
 
     private JNIMethodId javaLangReflectConstructorDeclaringClassName;
 
-    final JNIMethodId javaUtilLocaleToLanguageTag;
-    final JNIFieldId javaUtilResourceBundleParentField;
-    final JNIMethodId javaUtilResourceBundleGetLocale;
+    private JNIMethodId javaUtilLocaleToLanguageTag = WordFactory.nullPointer();
+    private JNIFieldId javaUtilResourceBundleParentField = WordFactory.nullPointer();
+    private JNIMethodId javaUtilResourceBundleGetLocale = WordFactory.nullPointer();
 
     NativeImageAgentJNIHandleSet(JNIEnvironment env) {
         super(env);
@@ -102,11 +102,6 @@ public class NativeImageAgentJNIHandleSet extends JNIHandleSet {
         javaLangInvokeWrongMethodTypeException = newClassGlobalRef(env, "java/lang/invoke/WrongMethodTypeException");
         javaLangIllegalArgumentException = newClassGlobalRef(env, "java/lang/IllegalArgumentException");
 
-        JNIObjectHandle javaUtilLocale = findClass(env, "java/util/Locale");
-        javaUtilLocaleToLanguageTag = getMethodId(env, javaUtilLocale, "toLanguageTag", "()Ljava/lang/String;", false);
-        JNIObjectHandle javaUtilResourceBundle = findClass(env, "java/util/ResourceBundle");
-        javaUtilResourceBundleParentField = getFieldId(env, javaUtilResourceBundle, "parent", "Ljava/util/ResourceBundle;", false);
-        javaUtilResourceBundleGetLocale = getMethodId(env, javaUtilResourceBundle, "getLocale", "()Ljava/util/Locale;", false);
     }
 
     JNIMethodId getJavaLangInvokeMethodTypeReturnType(JNIEnvironment env) {
@@ -176,4 +171,28 @@ JNIMethodId getJavaLangReflectConstructorDeclaringClassName(JNIEnvironment env,
         }
         return javaLangReflectConstructorDeclaringClassName;
     }
+
+    public JNIMethodId getJavaUtilLocaleToLanguageTag(JNIEnvironment env) {
+        if (javaUtilLocaleToLanguageTag.isNull()) {
+            JNIObjectHandle javaUtilLocale = findClass(env, "java/util/Locale");
+            javaUtilLocaleToLanguageTag = getMethodId(env, javaUtilLocale, "toLanguageTag", "()Ljava/lang/String;", false);
+        }
+        return javaUtilLocaleToLanguageTag;
+    }
+
+    public JNIFieldId getJavaUtilResourceBundleParentField(JNIEnvironment env) {
+        if (javaUtilResourceBundleParentField.isNull()) {
+            JNIObjectHandle javaUtilResourceBundle = findClass(env, "java/util/ResourceBundle");
+            javaUtilResourceBundleParentField = getFieldId(env, javaUtilResourceBundle, "parent", "Ljava/util/ResourceBundle;", false);
+        }
+        return javaUtilResourceBundleParentField;
+    }
+
+    public JNIMethodId getJavaUtilResourceBundleGetLocale(JNIEnvironment env) {
+        if (javaUtilResourceBundleGetLocale.isNull()) {
+            JNIObjectHandle javaUtilResourceBundle = findClass(env, "java/util/ResourceBundle");
+            javaUtilResourceBundleGetLocale = getMethodId(env, javaUtilResourceBundle, "getLocale", "()Ljava/util/Locale;", false);
+        }
+        return javaUtilResourceBundleGetLocale;
+    }
 }