Deprecate SymbolicLinkUtils in favour of Java 7 java.nio.file.Files APIs

src/main/org/apache/tools/ant/DirectoryScanner.java

@@ -20,6 +20,9 @@ package org.apache.tools.ant;
 
 import java.io.File;
 import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
@@ -44,7 +47,6 @@ import org.apache.tools.ant.types.selectors.SelectorUtils;
 import org.apache.tools.ant.types.selectors.TokenizedPath;
 import org.apache.tools.ant.types.selectors.TokenizedPattern;
 import org.apache.tools.ant.util.FileUtils;
-import org.apache.tools.ant.util.SymbolicLinkUtils;
 import org.apache.tools.ant.util.VectorSet;
 
 /**
@@ -227,10 +229,6 @@ public class DirectoryScanner
     /** Helper. */
     private static final FileUtils FILE_UTILS = FileUtils.getFileUtils();
 
-    /** Helper. */
-    private static final SymbolicLinkUtils SYMLINK_UTILS =
-        SymbolicLinkUtils.getSymbolicLinkUtils();
-
     /**
      * Patterns which should be excluded by default.
      *
@@ -874,7 +872,7 @@ public class DirectoryScanner
                 excludes = nullExcludes ? new String[0] : excludes;
 
                 if (basedir != null && !followSymlinks
-                    && SYMLINK_UTILS.isSymbolicLink(basedir)) {
+                    && Files.isSymbolicLink(basedir.toPath())) {
                     notFollowedSymlinks.add(basedir.getAbsolutePath());
                     basedir = null;
                 }
@@ -919,8 +917,6 @@ public class DirectoryScanner
                 includes = nullIncludes ? null : includes;
                 excludes = nullExcludes ? null : excludes;
             }
-        } catch (final IOException ex) {
-            throw new BuildException(ex);
         } finally {
             basedir = savedBase;
             synchronized (scanLock) {
@@ -1220,25 +1216,23 @@ public class DirectoryScanner
         }
         if (!followSymlinks) {
             final ArrayList<String> noLinks = new ArrayList<>();
-            for (String newfile : newfiles) {
-                try {
-                    if (SYMLINK_UTILS.isSymbolicLink(dir, newfile)) {
-                        final String name = vpath + newfile;
-                        final File file = new File(dir, newfile);
-                        if (file.isDirectory()) {
-                            dirsExcluded.addElement(name);
-                        } else if (file.isFile()) {
-                            filesExcluded.addElement(name);
-                        }
-                        accountForNotFollowedSymlink(name, file);
-                    } else {
-                        noLinks.add(newfile);
+            for (final String newfile : newfiles) {
+                final Path filePath;
+                if (dir == null) {
+                    filePath = Paths.get(newfile);
+                } else {
+                    filePath = Paths.get(dir.toPath().toString(), newfile);
+                }
+                if (Files.isSymbolicLink(filePath)) {
+                    final String name = vpath + newfile;
+                    final File file = new File(dir, newfile);
+                    if (file.isDirectory()) {
+                        dirsExcluded.addElement(name);
+                    } else if (file.isFile()) {
+                        filesExcluded.addElement(name);
                     }
-                } catch (final IOException ioe) {
-                    final String msg = "IOException caught while checking "
-                        + "for links, couldn't get canonical path!";
-                    // will be caught and redirected to Ant's logging system
-                    System.err.println(msg);
+                    accountForNotFollowedSymlink(name, file);
+                } else {
                     noLinks.add(newfile);
                 }
             }
@@ -1815,9 +1809,15 @@ public class DirectoryScanner
     private boolean causesIllegalSymlinkLoop(final String dirName, final File parent,
                                              final Deque<String> directoryNamesFollowed) {
         try {
+            final Path dirPath;
+            if (parent == null) {
+                dirPath = Paths.get(dirName);
+            } else {
+                dirPath = Paths.get(parent.toPath().toString(), dirName);
+            }
             if (directoryNamesFollowed.size() >= maxLevelsOfSymlinks
                 && Collections.frequency(directoryNamesFollowed, dirName) >= maxLevelsOfSymlinks
-                && SYMLINK_UTILS.isSymbolicLink(parent, dirName)) {
+                && Files.isSymbolicLink(dirPath)) {
 
                 final List<String> files = new ArrayList<>();
                 File f = FILE_UTILS.resolveFile(parent, dirName);

src/main/org/apache/tools/ant/taskdefs/Delete.java

@@ -19,7 +19,9 @@
 package org.apache.tools.ant.taskdefs;
 
 import java.io.File;
-import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
 import java.util.Arrays;
 import java.util.Comparator;
 import java.util.Iterator;
@@ -61,7 +63,6 @@ import org.apache.tools.ant.types.selectors.SelectSelector;
 import org.apache.tools.ant.types.selectors.SizeSelector;
 import org.apache.tools.ant.types.selectors.modifiedselector.ModifiedSelector;
 import org.apache.tools.ant.util.FileUtils;
-import org.apache.tools.ant.util.SymbolicLinkUtils;
 
 /**
  * Deletes a file or directory, or set of files defined by a fileset.
@@ -81,8 +82,6 @@ public class Delete extends MatchingTask {
     private static final ResourceComparator REVERSE_FILESYSTEM = new Reverse(new FileSystem());
     private static final ResourceSelector EXISTS = new Exists();
     private static FileUtils FILE_UTILS = FileUtils.getFileUtils();
-    private static SymbolicLinkUtils SYMLINK_UTILS =
-        SymbolicLinkUtils.getSymbolicLinkUtils();
 
     private static class ReverseDirs implements ResourceCollection {
 
@@ -715,12 +714,15 @@ public class Delete extends MatchingTask {
                         System.arraycopy(n, 0, links, 0, n.length);
                         Arrays.sort(links, Comparator.reverseOrder());
                         for (int l = 0; l < links.length; l++) {
-                            try {
-                                SYMLINK_UTILS
-                                    .deleteSymbolicLink(new File(links[l]),
-                                                        this);
-                            } catch (java.io.IOException ex) {
-                                handle(ex);
+                            final Path filePath = Paths.get(links[l]);
+                            if (!Files.isSymbolicLink(filePath)) {
+                                // it's not a symbolic link, so move on
+                                continue;
+                            }
+                            // it's a symbolic link, so delete it
+                            final boolean deleted = filePath.toFile().delete();
+                            if (!deleted) {
+                                handle("Could not delete symbolic link at " + filePath);
                             }
                         }
                     }
@@ -876,14 +878,13 @@ public class Delete extends MatchingTask {
         }
     }
 
-    private boolean isDanglingSymlink(File f) {
-        try {
-            return SYMLINK_UTILS.isDanglingSymbolicLink(f);
-        } catch (IOException e) {
-            log("Error while trying to detect " + f.getAbsolutePath()
-                + " as broken symbolic link. " + e.getMessage(),
-                quiet ? Project.MSG_VERBOSE : verbosity);
+    private boolean isDanglingSymlink(final File f) {
+        if (!Files.isSymbolicLink(f.toPath())) {
+            // it's not a symlink, so clearly it's not a dangling one
             return false;
         }
+        // it's a symbolic link, now  check the existence of the (target) file (by "following links")
+        final boolean targetFileExists = Files.exists(f.toPath());
+        return !targetFileExists;
     }
 }

src/main/org/apache/tools/ant/types/selectors/TokenizedPath.java

@@ -19,11 +19,12 @@
 package org.apache.tools.ant.types.selectors;
 
 import java.io.File;
-import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
 
 import org.apache.tools.ant.BuildException;
 import org.apache.tools.ant.util.FileUtils;
-import org.apache.tools.ant.util.SymbolicLinkUtils;
 
 /**
  * Container for a path that has been split into its components.
@@ -39,9 +40,6 @@ public class TokenizedPath {
 
     /** Helper. */
     private static final FileUtils FILE_UTILS = FileUtils.getFileUtils();
-    /** Helper. */
-    private static final SymbolicLinkUtils SYMLINK_UTILS =
-        SymbolicLinkUtils.getSymbolicLinkUtils();
     /** iterations for case-sensitive scanning. */
     private static final boolean[] CS_SCAN_ONLY = new boolean[] {true};
     /** iterations for non-case-sensitive scanning. */
@@ -142,22 +140,16 @@ public class TokenizedPath {
      */
     public boolean isSymlink(File base) {
         for (int i = 0; i < tokenizedPath.length; i++) {
-            try {
-                if ((base != null
-                     && SYMLINK_UTILS.isSymbolicLink(base, tokenizedPath[i]))
-                    ||
-                    (base == null
-                     && SYMLINK_UTILS.isSymbolicLink(tokenizedPath[i]))
-                    ) {
-                    return true;
-                }
-                base = new File(base, tokenizedPath[i]);
-            } catch (IOException ioe) {
-                String msg = "IOException caught while checking "
-                    + "for links, couldn't get canonical path!";
-                // will be caught and redirected to Ant's logging system
-                System.err.println(msg);
+            final Path pathToTraverse;
+            if (base == null) {
+                pathToTraverse = Paths.get(tokenizedPath[i]);
+            } else {
+                pathToTraverse = Paths.get(base.toPath().toString(), tokenizedPath[i]);
+            }
+            if (Files.isSymbolicLink(pathToTraverse)) {
+                return true;
             }
+            base = new File(base, tokenizedPath[i]);
         }
         return false;
     }

src/main/org/apache/tools/ant/util/FileUtils.java

@@ -33,6 +33,7 @@ import java.net.URLConnection;
 import java.nio.channels.Channel;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.nio.file.Paths;
 import java.nio.file.StandardOpenOption;
 import java.text.DecimalFormat;
 import java.util.ArrayList;
@@ -1141,16 +1142,15 @@ public class FileUtils {
      * @return true if the file is a symbolic link.
      * @throws IOException on error.
      * @since Ant 1.5
-     * @deprecated use SymbolicLinkUtils instead
+     * @deprecated use {@link Files#isSymbolicLink(Path)} instead
      */
     @Deprecated
-    public boolean isSymbolicLink(File parent, String name)
+    public boolean isSymbolicLink(final File parent, final String name)
         throws IOException {
-        SymbolicLinkUtils u = SymbolicLinkUtils.getSymbolicLinkUtils();
         if (parent == null) {
-            return u.isSymbolicLink(name);
+            return Files.isSymbolicLink(Paths.get(name));
         }
-        return u.isSymbolicLink(parent, name);
+        return Files.isSymbolicLink(Paths.get(parent.toPath().toString(), name));
     }
 
     /**

src/main/org/apache/tools/ant/util/SymbolicLinkUtils.java

@@ -30,6 +30,9 @@ import org.apache.tools.ant.taskdefs.Execute;
  * a symbolic link based on the absent support for them in Java.
  *
  * @since Ant 1.8.0
+ * @deprecated Starting Ant 1.10.2, this class is now deprecated in favour
+ *              of the Java {@link java.nio.file.Files} APIs introduced in
+ *              Java 7, for dealing with symbolic links
  */
 public class SymbolicLinkUtils {
     private static final FileUtils FILE_UTILS = FileUtils.getFileUtils();