src/java.base/share/classes/java/nio/file/Path.java

*** 1,7 ****
  /*
!  * Copyright (c) 2007, 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
--- 1,7 ----
  /*
!  * Copyright (c) 2007, 2018, 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
*** 28,37 ****
--- 28,39 ----
  import java.io.File;
  import java.io.IOException;
  import java.net.URI;
  import java.util.Iterator;
  import java.util.NoSuchElementException;
+ import java.util.Objects;
+ import java.util.stream.Stream;
  
  /**
   * An object that may be used to locate a file in a file system. It will
   * typically represent a system dependent file path.
   *
*** 321,330 ****
--- 323,369 ----
      default boolean endsWith(String other) {
          return endsWith(getFileSystem().getPath(other));
      }
  
      /**
+      * Returns whether the extension of this path is in a specified list.
+      * The extension is that portion of the path after the last dot
+      * ({@code '.'}).  If this path is empty, ends with a dot, or has a
+      * {@link FileSystem#getSeparator() name-separator} after the last dot,
+      * or the parameter is empty, then this method returns {@code false}.
+      * Any arguments in the parameter which are either empty or contain a
+      * dot are ignored.
+      *
+      * @param   extensions
+      *          the extensions to be checked
+      *
+      * @return  whether this path has one of the specified extensions
+      */
+     default boolean hasExtension(String... extensions) {
+         Objects.requireNonNull(extensions);
+ 
+         String path = toString();
+         if (path.isEmpty()) {
+             return false;
+         }
+ 
+         int lastDot = path.lastIndexOf(".");
+         if (lastDot == path.length() - 1) {
+             return false;
+         }
+ 
+         String separator = getFileSystem().getSeparator();
+         if (path.indexOf(separator, lastDot) != -1) {
+             return false;
+         }
+ 
+         return Stream.of(extensions)
+             .filter(e -> !e.isEmpty() && !e.contains("."))
+             .anyMatch(path::endsWith);
+     }
+ 
+     /**
       * Returns a path that is this path with redundant name elements eliminated.
       *
       * <p> The precise definition of this method is implementation dependent but
       * in general it derives from this path, a path that does not contain
       * <em>redundant</em> name elements. In many file systems, the "{@code .}"