1 /* 2 * Copyright (c) 2008, 2019, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package sun.nio.fs; 27 28 import java.nio.file.*; 29 import java.io.IOException; 30 31 /** 32 * File type detector that does lookup of file extension using Windows Registry. 33 */ 34 35 public class RegistryFileTypeDetector 36 extends AbstractFileTypeDetector 37 { 38 public RegistryFileTypeDetector() { 39 super(); 40 } 41 42 @Override 43 public String implProbeContentType(Path file) throws IOException { 44 if (!(file instanceof Path)) 45 return null; 46 47 // get file extension 48 Path name = file.getFileName(); 49 if (name == null) 50 return null; 51 String filename = name.toString(); 52 int dot = filename.lastIndexOf('.'); 53 if ((dot < 0) || (dot == (filename.length()-1))) 54 return null; 55 56 // query HKEY_CLASSES_ROOT\<ext> 57 String key = filename.substring(dot); 58 NativeBuffer keyBuffer = WindowsNativeDispatcher.asNativeBuffer(key); 59 NativeBuffer nameBuffer = WindowsNativeDispatcher.asNativeBuffer("Content Type"); 60 try { 61 return queryStringValue(keyBuffer.address(), nameBuffer.address()); 62 } finally { 63 nameBuffer.release(); 64 keyBuffer.release(); 65 } 66 } 67 68 private static native String queryStringValue(long subKey, long name); 69 70 static { 71 // nio.dll has dependency on net.dll 72 jdk.internal.access.SharedSecrets.getJavaLangAccess().loadLibrary("net"); 73 jdk.internal.access.SharedSecrets.getJavaLangAccess().loadLibrary("nio"); 74 } 75 }