Copy platforms and samples from ndk/ source tree.

The idea is to allow developing the NDK in the open, while
having the platforms and samples under a private branch until
the corresponding release are open-sourced.

Change-Id: Iee995fb6c4d3ee1387dea7486e599e079c9e4c6d

ndk/samples/hello-jni/src/com/example/hellojni/HelloJni.java

@@ -0,0 +1,66 @@
+/*
+ * Copyright (C) 2009 The Android Open Source Project
+ *
+ * Licensed 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 com.example.hellojni;
+
+import android.app.Activity;
+import android.widget.TextView;
+import android.os.Bundle;
+
+
+public class HelloJni extends Activity
+{
+    /** Called when the activity is first created. */
+    @Override
+    public void onCreate(Bundle savedInstanceState)
+    {
+        super.onCreate(savedInstanceState);
+
+        /* Create a TextView and set its content.
+         * the text is retrieved by calling a native
+         * function.
+         */
+        TextView  tv = new TextView(this);
+        tv.setText( stringFromJNI() );
+        setContentView(tv);
+    }
+
+    /* A native method that is implemented by the
+     * 'hello-jni' native library, which is packaged
+     * with this application.
+     */
+    public native String  stringFromJNI();
+
+    /* This is another native method declaration that is *not*
+     * implemented by 'hello-jni'. This is simply to show that
+     * you can declare as many native methods in your Java code
+     * as you want, their implementation is searched in the
+     * currently loaded native libraries only the first time
+     * you call them.
+     *
+     * Trying to call this function will result in a
+     * java.lang.UnsatisfiedLinkError exception !
+     */
+    public native String  unimplementedStringFromJNI();
+
+    /* this is used to load the 'hello-jni' library on application
+     * startup. The library has already been unpacked into
+     * /data/data/com.example.HelloJni/lib/libhello-jni.so at
+     * installation time by the package manager.
+     */
+    static {
+        System.loadLibrary("hello-jni");
+    }
+}