--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/api/scripting/URLReader.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,121 @@
+/*
+ * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package jdk.nashorn.api.scripting;
+
+import java.io.CharArrayReader;
+import java.io.IOException;
+import java.io.Reader;
+import java.net.URL;
+import java.nio.charset.Charset;
+import java.util.Objects;
+import jdk.nashorn.internal.runtime.Source;
+
+/**
+ * A Reader that reads from a URL. Used to make sure that the reader
+ * reads content from given URL and can be trusted to do so.
+ *
+ * @since 1.8u40
+ */
+public final class URLReader extends Reader {
+    // underlying URL
+    private final URL url;
+    // Charset used to convert
+    private final Charset cs;
+
+    // lazily initialized underlying reader for URL
+    private Reader reader;
+
+    /**
+     * Constructor
+     *
+     * @param url URL for this URLReader
+     * @throws NullPointerException if url is null
+     */
+    public URLReader(final URL url) {
+        this(url, (Charset)null);
+    }
+
+    /**
+     * Constructor
+     *
+     * @param url URL for this URLReader
+     * @param charsetName  Name of the Charset used to convert bytes to chars
+     * @throws NullPointerException if url is null
+     */
+    public URLReader(final URL url, final String charsetName) {
+        this(url, Charset.forName(charsetName));
+    }
+
+    /**
+     * Constructor
+     *
+     * @param url URL for this URLReader
+     * @param cs  Charset used to convert bytes to chars
+     * @throws NullPointerException if url is null
+     */
+    public URLReader(final URL url, final Charset cs) {
+        this.url = Objects.requireNonNull(url);
+        this.cs  = cs;
+    }
+
+    @Override
+    public int read(final char cbuf[], final int off, final int len) throws IOException {
+        return getReader().read(cbuf, off, len);
+    }
+
+    @Override
+    public void close() throws IOException {
+        getReader().close();
+    }
+
+    /**
+     * URL of this reader
+     * @return the URL from which this reader reads.
+     */
+    public URL getURL() {
+        return url;
+    }
+
+    /**
+     * Charset used by this reader
+     *
+     * @return the Charset used to convert bytes to chars
+     */
+    public Charset getCharset() {
+        return cs;
+    }
+
+    // lazily initialize char array reader using URL content
+    private Reader getReader() throws IOException {
+        synchronized (lock) {
+            if (reader == null) {
+                reader = new CharArrayReader(Source.readFully(url, cs));
+            }
+        }
+
+        return reader;
+    }
+}