--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.base/share/classes/java/util/UnknownFormatFlagsException.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2003, 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 java.util;
+
+/**
+ * Unchecked exception thrown when an unknown flag is given.
+ *
+ * <p> Unless otherwise specified, passing a {@code null} argument to any
+ * method or constructor in this class will cause a {@link
+ * NullPointerException} to be thrown.
+ *
+ * @since 1.5
+ */
+public class UnknownFormatFlagsException extends IllegalFormatException {
+
+    private static final long serialVersionUID = 19370506L;
+
+    private String flags;
+
+    /**
+     * Constructs an instance of this class with the specified flags.
+     *
+     * @param  f
+     *         The set of format flags which contain an unknown flag
+     */
+    public UnknownFormatFlagsException(String f) {
+        if (f == null)
+            throw new NullPointerException();
+        this.flags = f;
+    }
+
+    /**
+     * Returns the set of flags which contains an unknown flag.
+     *
+     * @return  The flags
+     */
+    public String getFlags() {
+        return flags;
+    }
+
+    // javadoc inherited from Throwable.java
+    public String getMessage() {
+        return "Flags = " + flags;
+    }
+}