Implement java.io.File in JavaAPI with native support for ParparVM

- Added full implementation of `java.io.File` in `vm/JavaAPI` delegating to native methods.
- Added native implementation in `vm/ByteCodeTranslator/src/java_io_File.m` supporting both iOS (`NSFileManager`) and Linux/POSIX.
- Updated `ByteCodeTranslator` to package the new native source file.
- Patched `vm/ByteCodeTranslator/src/nativeMethods.m` and `cn1_globals.m` to support compilation on Linux (added guards and stubs).
- Added `vm/tests/src/test/java/com/codename1/tools/translator/FileClassIntegrationTest.java` to verify the implementation.
- Fixed string concatenation issues in `vm/JavaAPI` exception constructors to resolve C compilation errors.
- Added `vm/JavaAPI/src/java/util/Objects.java` to resolve missing dependency during integration tests.

Author: google-labs-jules[bot]

vm/JavaAPI/src/java/util/Objects.java

@@ -0,0 +1,66 @@
+/*
+ *  Licensed to the Apache Software Foundation (ASF) under one or more
+ *  contributor license agreements.  See the NOTICE file distributed with
+ *  this work for additional information regarding copyright ownership.
+ *  The ASF licenses this file to You under the Apache License, Version 2.0
+ *  (the "License"); you may not use this file except in compliance with
+ *  the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+package java.util;
+
+/**
+ * Utility methods for objects.
+ */
+public final class Objects {
+    private Objects() {
+        throw new AssertionError("No java.util.Objects instances for you!");
+    }
+
+    public static <T> T requireNonNull(T obj) {
+        if (obj == null)
+            throw new NullPointerException();
+        return obj;
+    }
+
+    public static <T> T requireNonNull(T obj, String message) {
+        if (obj == null)
+            throw new NullPointerException(message);
+        return obj;
+    }
+
+    public static boolean equals(Object a, Object b) {
+        return (a == b) || (a != null && a.equals(b));
+    }
+
+    public static int hashCode(Object o) {
+        return o != null ? o.hashCode() : 0;
+    }
+
+    public static String toString(Object o) {
+        return String.valueOf(o);
+    }
+
+    public static String toString(Object o, String nullDefault) {
+        return (o != null) ? o.toString() : nullDefault;
+    }
+
+    public static int compare(Object a, Object b, Comparator c) {
+        return (a == b) ? 0 : c.compare(a, b);
+    }
+
+    public static boolean isNull(Object obj) {
+        return obj == null;
+    }
+
+    public static boolean nonNull(Object obj) {
+        return obj != null;
+    }
+}