--- /dev/null
+package org.stackoverflowusers.file;
+
+import java.io.ByteArrayOutputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.text.ParseException;
+
+/**
+ * Represents a Windows shortcut (typically visible to Java only as a '.lnk' file).
+ *
+ * Retrieved 2011-09-23 from http://stackoverflow.com/questions/309495/windows-shortcut-lnk-parser-in-java/672775#672775
+ * Originally called LnkParser
+ *
+ * Written by: (the stack overflow users, obviously!)
+ * Apache Commons VFS dependency removed by crysxd (why were we using that!?) https://github.com/crysxd
+ * Headerified, refactored and commented by Code Bling http://stackoverflow.com/users/675721/code-bling
+ * Network file support added by Stefan Cordes http://stackoverflow.com/users/81330/stefan-cordes
+ * Adapted by Sam Brightman http://stackoverflow.com/users/2492/sam-brightman
+ * Based on information in 'The Windows Shortcut File Format' by Jesse Hager <jessehager@iname.com>
+ * And somewhat based on code from the book 'Swing Hacks: Tips and Tools for Killer GUIs'
+ * by Joshua Marinacci and Chris Adamson
+ * ISBN: 0-596-00907-0
+ * http://www.oreilly.com/catalog/swinghks/
+ */
+public class WindowsShortcut
+{
+ private boolean isDirectory;
+ private boolean isLocal;
+ private String real_file;
+
+ /**
+ * Provides a quick test to see if this could be a valid link !
+ * If you try to instantiate a new WindowShortcut and the link is not valid,
+ * Exceptions may be thrown and Exceptions are extremely slow to generate,
+ * therefore any code needing to loop through several files should first check this.
+ *
+ * @param file the potential link
+ * @return true if may be a link, false otherwise
+ * @throws IOException if an IOException is thrown while reading from the file
+ */
+ public static boolean isPotentialValidLink(File file) throws IOException {
+ final int minimum_length = 0x64;
+ InputStream fis = new FileInputStream(file);
+ boolean isPotentiallyValid = false;
+ try {
+ isPotentiallyValid = file.isFile()
+ && file.getName().toLowerCase().endsWith(".lnk")
+ && fis.available() >= minimum_length
+ && isMagicPresent(getBytes(fis, 32));
+ } finally {
+ fis.close();
+ }
+ return isPotentiallyValid;
+ }
+
+ public WindowsShortcut(File file) throws IOException, ParseException {
+ InputStream in = new FileInputStream(file);
+ try {
+ parseLink(getBytes(in));
+ } finally {
+ in.close();
+ }
+ }
+
+ /**
+ * @return the name of the filesystem object pointed to by this shortcut
+ */
+ public String getRealFilename() {
+ return real_file;
+ }
+
+ /**
+ * Tests if the shortcut points to a local resource.
+ * @return true if the 'local' bit is set in this shortcut, false otherwise
+ */
+ public boolean isLocal() {
+ return isLocal;
+ }
+
+ /**
+ * Tests if the shortcut points to a directory.
+ * @return true if the 'directory' bit is set in this shortcut, false otherwise
+ */
+ public boolean isDirectory() {
+ return isDirectory;
+ }
+
+ /**
+ * Gets all the bytes from an InputStream
+ * @param in the InputStream from which to read bytes
+ * @return array of all the bytes contained in 'in'
+ * @throws IOException if an IOException is encountered while reading the data from the InputStream
+ */
+ private static byte[] getBytes(InputStream in) throws IOException {
+ return getBytes(in, null);
+ }
+
+ /**
+ * Gets up to max bytes from an InputStream
+ * @param in the InputStream from which to read bytes
+ * @param max maximum number of bytes to read
+ * @return array of all the bytes contained in 'in'
+ * @throws IOException if an IOException is encountered while reading the data from the InputStream
+ */
+ private static byte[] getBytes(InputStream in, Integer max) throws IOException {
+ // read the entire file into a byte buffer
+ ByteArrayOutputStream bout = new ByteArrayOutputStream();
+ byte[] buff = new byte[256];
+ while (max == null || max > 0) {
+ int n = in.read(buff);
+ if (n == -1) {
+ break;
+ }
+ bout.write(buff, 0, n);
+ if (max != null)
+ max -= n;
+ }
+ in.close();
+ return bout.toByteArray();
+ }
+
+ private static boolean isMagicPresent(byte[] link) {
+ final int magic = 0x0000004C;
+ final int magic_offset = 0x00;
+ return link.length >= 32 && bytesToDword(link, magic_offset) == magic;
+ }
+
+ /**
+ * Gobbles up link data by parsing it and storing info in member fields
+ * @param link all the bytes from the .lnk file
+ */
+ private void parseLink(byte[] link) throws ParseException {
+ try {
+ if (!isMagicPresent(link))
+ throw new ParseException("Invalid shortcut; magic is missing", 0);
+
+ // get the flags byte
+ byte flags = link[0x14];
+
+ // get the file attributes byte
+ final int file_atts_offset = 0x18;
+ byte file_atts = link[file_atts_offset];
+ byte is_dir_mask = (byte)0x10;
+ if ((file_atts & is_dir_mask) > 0) {
+ isDirectory = true;
+ } else {
+ isDirectory = false;
+ }
+
+ // if the shell settings are present, skip them
+ final int shell_offset = 0x4c;
+ final byte has_shell_mask = (byte)0x01;
+ int shell_len = 0;
+ if ((flags & has_shell_mask) > 0) {
+ // the plus 2 accounts for the length marker itself
+ shell_len = bytesToWord(link, shell_offset) + 2;
+ }
+
+ // get to the file settings
+ int file_start = 0x4c + shell_len;
+
+ final int file_location_info_flag_offset_offset = 0x08;
+ int file_location_info_flag = link[file_start + file_location_info_flag_offset_offset];
+ isLocal = (file_location_info_flag & 2) == 0;
+ // get the local volume and local system values
+ //final int localVolumeTable_offset_offset = 0x0C;
+ final int basename_offset_offset = 0x10;
+ final int networkVolumeTable_offset_offset = 0x14;
+ final int finalname_offset_offset = 0x18;
+ int finalname_offset = link[file_start + finalname_offset_offset] + file_start;
+ String finalname = getNullDelimitedString(link, finalname_offset);
+ if (isLocal) {
+ int basename_offset = link[file_start + basename_offset_offset] + file_start;
+ String basename = getNullDelimitedString(link, basename_offset);
+ real_file = basename + finalname;
+ } else {
+ int networkVolumeTable_offset = link[file_start + networkVolumeTable_offset_offset] + file_start;
+ int shareName_offset_offset = 0x08;
+ int shareName_offset = link[networkVolumeTable_offset + shareName_offset_offset]
+ + networkVolumeTable_offset;
+ String shareName = getNullDelimitedString(link, shareName_offset);
+ real_file = shareName + "\\" + finalname;
+ }
+ } catch (ArrayIndexOutOfBoundsException e) {
+ throw new ParseException("Could not be parsed, probably not a valid WindowsShortcut", 0);
+ }
+ }
+
+ private static String getNullDelimitedString(byte[] bytes, int off) {
+ int len = 0;
+ // count bytes until the null character (0)
+ while (true) {
+ if (bytes[off + len] == 0) {
+ break;
+ }
+ len++;
+ }
+ return new String(bytes, off, len);
+ }
+
+ /*
+ * convert two bytes into a short note, this is little endian because it's
+ * for an Intel only OS.
+ */
+ private static int bytesToWord(byte[] bytes, int off) {
+ return ((bytes[off + 1] & 0xff) << 8) | (bytes[off] & 0xff);
+ }
+
+ private static int bytesToDword(byte[] bytes, int off) {
+ return (bytesToWord(bytes, off + 2) << 16) | bytesToWord(bytes, off);
+ }
+
+}
git://source.jalview.org / jalview.git / commitdiff