[MCLEAN-126] Replaced old File API with new Path equivalent where possible (#62)

Author: peterdemaeyer

src/main/java/org/apache/maven/plugins/clean/CleanMojo.java

@@ -20,6 +20,8 @@
 
 import java.io.File;
 import java.io.IOException;
+import java.nio.file.FileSystems;
+import java.nio.file.Path;
 
 import org.apache.maven.execution.MavenSession;
 import org.apache.maven.plugin.AbstractMojo;
@@ -183,7 +185,7 @@ public class CleanMojo extends AbstractMojo {
      * <code>${maven.multiModuleProjectDirectory}/target/.clean</code> directory will be used.  If the
      * <code>${build.directory}</code> has been modified, you'll have to adjust this property explicitly.
      * In order for fast clean to work correctly, this directory and the various directories that will be deleted
-     * should usually reside on the same volume. The exact conditions are system dependant though, but if an atomic
+     * should usually reside on the same volume.  The exact conditions are system-dependent though, but if an atomic
      * move is not supported, the standard deletion mechanism will be used.
      *
      * @see #fast
@@ -196,8 +198,8 @@ public class CleanMojo extends AbstractMojo {
      * Mode to use when using fast clean.  Values are: <code>background</code> to start deletion immediately and
      * waiting for all files to be deleted when the session ends, <code>at-end</code> to indicate that the actual
      * deletion should be performed synchronously when the session ends, or <code>defer</code> to specify that
-     * the actual file deletion should be started in the background when the session ends (this should only be used
-     * when maven is embedded in a long running process).
+     * the actual file deletion should be started in the background when the session ends.  This should only be used
+     * when maven is embedded in a long-running process.
      *
      * @see #fast
      * @since 3.2
@@ -223,11 +225,14 @@ public void execute() throws MojoExecutionException {
 
         String multiModuleProjectDirectory =
                 session != null ? session.getSystemProperties().getProperty("maven.multiModuleProjectDirectory") : null;
-        File fastDir;
+        Path fastDir;
         if (fast && this.fastDir != null) {
-            fastDir = this.fastDir;
+            fastDir = toNullablePath(this.fastDir);
         } else if (fast && multiModuleProjectDirectory != null) {
-            fastDir = new File(multiModuleProjectDirectory, "target/.clean");
+            fastDir = FileSystems.getDefault()
+                    .getPath(multiModuleProjectDirectory)
+                    .resolve("target")
+                    .resolve(".clean");
         } else {
             fastDir = null;
             if (fast) {
@@ -247,7 +252,7 @@ public void execute() throws MojoExecutionException {
         Cleaner cleaner = new Cleaner(session, getLog(), isVerbose(), fastDir, fastMode);
 
         try {
-            for (File directoryItem : getDirectories()) {
+            for (Path directoryItem : getDirectories()) {
                 if (directoryItem != null) {
                     cleaner.delete(directoryItem, null, followSymLinks, failOnError, retryOnError);
                 }
@@ -270,7 +275,11 @@ public void execute() throws MojoExecutionException {
                         selector = null;
                     }
                     cleaner.delete(
-                            fileset.getDirectory(), selector, fileset.isFollowSymlinks(), failOnError, retryOnError);
+                            fileset.getDirectory().toPath(),
+                            selector,
+                            fileset.isFollowSymlinks(),
+                            failOnError,
+                            retryOnError);
                 }
             }
         } catch (IOException e) {
@@ -292,13 +301,22 @@ private boolean isVerbose() {
      *
      * @return The directories to clean or an empty array if none, never <code>null</code>.
      */
-    private File[] getDirectories() {
-        File[] directories;
+    private Path[] getDirectories() {
+        Path[] directories;
         if (excludeDefaultDirectories) {
-            directories = new File[0];
+            directories = new Path[0];
         } else {
-            directories = new File[] {directory, outputDirectory, testOutputDirectory, reportDirectory};
+            directories = new Path[] {
+                toNullablePath(directory),
+                toNullablePath(outputDirectory),
+                toNullablePath(testOutputDirectory),
+                toNullablePath(reportDirectory)
+            };
         }
         return directories;
     }
+
+    private static Path toNullablePath(File file) {
+        return file != null ? file.toPath() : null;
+    }
 }

src/main/java/org/apache/maven/plugins/clean/Cleaner.java

@@ -23,6 +23,7 @@
 import java.lang.reflect.InvocationHandler;
 import java.lang.reflect.Method;
 import java.lang.reflect.Proxy;
+import java.nio.file.DirectoryStream;
 import java.nio.file.Files;
 import java.nio.file.LinkOption;
 import java.nio.file.Path;
@@ -37,6 +38,9 @@
 import org.codehaus.plexus.util.Os;
 import org.eclipse.aether.SessionData;
 
+import static java.nio.file.Files.exists;
+import static java.nio.file.Files.isDirectory;
+import static java.nio.file.Files.newDirectoryStream;
 import static org.apache.maven.plugins.clean.CleanMojo.FAST_MODE_BACKGROUND;
 import static org.apache.maven.plugins.clean.CleanMojo.FAST_MODE_DEFER;
 
@@ -56,7 +60,7 @@ class Cleaner {
      */
     private final MavenSession session;
 
-    private final File fastDir;
+    private final Path fastDir;
 
     private final String fastMode;
 
@@ -73,7 +77,7 @@ class Cleaner {
      * @param fastDir  The explicit configured directory or to be deleted in fast mode.
      * @param fastMode The fast deletion mode.
      */
-    Cleaner(MavenSession session, final Log log, boolean verbose, File fastDir, String fastMode) {
+    Cleaner(MavenSession session, final Log log, boolean verbose, Path fastDir, String fastMode) {
         this.session = session;
         // This can't be null as the Cleaner gets it from the CleanMojo which gets it from AbstractMojo class, where it
         // is never null.
@@ -96,10 +100,10 @@ class Cleaner {
      * @throws IOException If a file/directory could not be deleted and <code>failOnError</code> is <code>true</code>.
      */
     public void delete(
-            File basedir, Selector selector, boolean followSymlinks, boolean failOnError, boolean retryOnError)
+            Path basedir, Selector selector, boolean followSymlinks, boolean failOnError, boolean retryOnError)
             throws IOException {
-        if (!basedir.isDirectory()) {
-            if (!basedir.exists()) {
+        if (!isDirectory(basedir)) {
+            if (!exists(basedir)) {
                 if (log.isDebugEnabled()) {
                     log.debug("Skipping non-existing directory " + basedir);
                 }
@@ -112,7 +116,7 @@ public void delete(
             log.info("Deleting " + basedir + (selector != null ? " (" + selector + ")" : ""));
         }
 
-        File file = followSymlinks ? basedir : basedir.getCanonicalFile();
+        Path file = followSymlinks ? basedir : basedir.toRealPath();
 
         if (selector == null && !followSymlinks && fastDir != null && session != null) {
             // If anything wrong happens, we'll just use the usual deletion mechanism
@@ -124,9 +128,7 @@ public void delete(
         delete(file, "", selector, followSymlinks, failOnError, retryOnError);
     }
 
-    private boolean fastDelete(File baseDirFile) {
-        Path baseDir = baseDirFile.toPath();
-        Path fastDir = this.fastDir.toPath();
+    private boolean fastDelete(Path baseDir) {
         // Handle the case where we use ${maven.multiModuleProjectDirectory}/target/.clean for example
         if (fastDir.toAbsolutePath().startsWith(baseDir.toAbsolutePath())) {
             try {
@@ -135,7 +137,7 @@ private boolean fastDelete(File baseDirFile) {
                 try {
                     Files.move(baseDir, tmpDir, StandardCopyOption.REPLACE_EXISTING);
                     if (session != null) {
-                        session.getRepositorySession().getData().set(LAST_DIRECTORY_TO_DELETE, baseDir.toFile());
+                        session.getRepositorySession().getData().set(LAST_DIRECTORY_TO_DELETE, baseDir);
                     }
                     baseDir = tmpDir;
                 } catch (IOException e) {
@@ -151,7 +153,7 @@ private boolean fastDelete(File baseDirFile) {
         }
         // Create fastDir and the needed parents if needed
         try {
-            if (!Files.isDirectory(fastDir)) {
+            if (!isDirectory(fastDir)) {
                 Files.createDirectories(fastDir);
             }
         } catch (IOException e) {
@@ -172,7 +174,7 @@ private boolean fastDelete(File baseDirFile) {
             // or any other exception occurs, an exception will be thrown in which case
             // the method will return false and the usual deletion will be performed.
             Files.move(baseDir, dstDir, StandardCopyOption.ATOMIC_MOVE);
-            BackgroundCleaner.delete(this, tmpDir.toFile(), fastMode);
+            BackgroundCleaner.delete(this, tmpDir, fastMode);
             return true;
         } catch (IOException e) {
             if (log.isDebugEnabled()) {
@@ -198,7 +200,7 @@ private boolean fastDelete(File baseDirFile) {
      * @throws IOException If a file/directory could not be deleted and <code>failOnError</code> is <code>true</code>.
      */
     private Result delete(
-            File file,
+            Path file,
             String pathname,
             Selector selector,
             boolean followSymlinks,
@@ -207,18 +209,16 @@ private Result delete(
             throws IOException {
         Result result = new Result();
 
-        boolean isDirectory = file.isDirectory();
+        boolean isDirectory = isDirectory(file);
 
         if (isDirectory) {
             if (selector == null || selector.couldHoldSelected(pathname)) {
-                if (followSymlinks || !isSymbolicLink(file.toPath())) {
-                    File canonical = followSymlinks ? file : file.getCanonicalFile();
-                    String[] filenames = canonical.list();
-                    if (filenames != null) {
-                        String prefix = pathname.length() > 0 ? pathname + File.separatorChar : "";
-                        for (int i = filenames.length - 1; i >= 0; i--) {
-                            String filename = filenames[i];
-                            File child = new File(canonical, filename);
+                if (followSymlinks || !isSymbolicLink(file)) {
+                    Path canonical = followSymlinks ? file : file.toRealPath();
+                    String prefix = pathname.length() > 0 ? pathname + File.separatorChar : "";
+                    try (DirectoryStream<Path> children = newDirectoryStream(canonical)) {
+                        for (Path child : children) {
+                            String filename = child.getFileName().toString();
                             result.update(delete(
                                     child, prefix + filename, selector, followSymlinks, failOnError, retryOnError));
                         }
@@ -235,7 +235,7 @@ private Result delete(
             String logmessage;
             if (isDirectory) {
                 logmessage = "Deleting directory " + file;
-            } else if (file.exists()) {
+            } else if (exists(file)) {
                 logmessage = "Deleting file " + file;
             } else {
                 logmessage = "Deleting dangling symlink " + file;
@@ -272,7 +272,7 @@ private boolean isSymbolicLink(Path path) throws IOException {
      * @return <code>0</code> if the file was deleted, <code>1</code> otherwise.
      * @throws IOException If a file/directory could not be deleted and <code>failOnError</code> is <code>true</code>.
      */
-    private int delete(File file, boolean failOnError, boolean retryOnError) throws IOException {
+    private int delete(Path file, boolean failOnError, boolean retryOnError) throws IOException {
         IOException failure = delete(file);
         if (failure != null) {
             boolean deleted = false;
@@ -290,10 +290,10 @@ private int delete(File file, boolean failOnError, boolean retryOnError) throws
                     } catch (InterruptedException e) {
                         // ignore
                     }
-                    deleted = delete(file) == null || !file.exists();
+                    deleted = delete(file) == null || !exists(file);
                 }
             } else {
-                deleted = !file.exists();
+                deleted = !exists(file);
             }
 
             if (!deleted) {
@@ -311,9 +311,9 @@ private int delete(File file, boolean failOnError, boolean retryOnError) throws
         return 0;
     }
 
-    private static IOException delete(File file) {
+    private static IOException delete(Path file) {
         try {
-            Files.delete(file.toPath());
+            Files.delete(file);
         } catch (IOException e) {
             return e;
         }
@@ -338,19 +338,19 @@ private static class BackgroundCleaner extends Thread {
         private static final int RUNNING = 1;
         private static final int STOPPED = 2;
         private static BackgroundCleaner instance;
-        private final Deque<File> filesToDelete = new ArrayDeque<>();
+        private final Deque<Path> filesToDelete = new ArrayDeque<>();
         private final Cleaner cleaner;
         private final String fastMode;
         private int status = NEW;
 
-        private BackgroundCleaner(Cleaner cleaner, File dir, String fastMode) {
+        private BackgroundCleaner(Cleaner cleaner, Path dir, String fastMode) throws IOException {
             super("mvn-background-cleaner");
             this.cleaner = cleaner;
             this.fastMode = fastMode;
             init(cleaner.fastDir, dir);
         }
 
-        public static void delete(Cleaner cleaner, File dir, String fastMode) {
+        public static void delete(Cleaner cleaner, Path dir, String fastMode) throws IOException {
             synchronized (BackgroundCleaner.class) {
                 if (instance == null || !instance.doDelete(dir)) {
                     instance = new BackgroundCleaner(cleaner, dir, fastMode);
@@ -368,7 +368,7 @@ static void sessionEnd() {
 
         public void run() {
             while (true) {
-                File basedir = pollNext();
+                Path basedir = pollNext();
                 if (basedir == null) {
                     break;
                 }
@@ -380,24 +380,23 @@ public void run() {
             }
         }
 
-        synchronized void init(File fastDir, File dir) {
-            if (fastDir.isDirectory()) {
-                File[] children = fastDir.listFiles();
-                if (children != null && children.length > 0) {
-                    for (File child : children) {
+        synchronized void init(Path fastDir, Path dir) throws IOException {
+            if (isDirectory(fastDir)) {
+                try (DirectoryStream<Path> children = newDirectoryStream(fastDir)) {
+                    for (Path child : children) {
                         doDelete(child);
                     }
                 }
             }
             doDelete(dir);
         }
 
-        synchronized File pollNext() {
-            File basedir = filesToDelete.poll();
+        synchronized Path pollNext() {
+            Path basedir = filesToDelete.poll();
             if (basedir == null) {
                 if (cleaner.session != null) {
                     SessionData data = cleaner.session.getRepositorySession().getData();
-                    File lastDir = (File) data.get(LAST_DIRECTORY_TO_DELETE);
+                    Path lastDir = (Path) data.get(LAST_DIRECTORY_TO_DELETE);
                     if (lastDir != null) {
                         data.set(LAST_DIRECTORY_TO_DELETE, null);
                         return lastDir;
@@ -409,7 +408,7 @@ synchronized File pollNext() {
             return basedir;
         }
 
-        synchronized boolean doDelete(File dir) {
+        synchronized boolean doDelete(Path dir) {
             if (status == STOPPED) {
                 return false;
             }

src/test/java/org/apache/maven/plugins/clean/CleanMojoTest.java

@@ -263,7 +263,7 @@ private void testSymlink(LinkCreator linkCreator) throws Exception {
         Files.write(file, Collections.singleton("Hello world"));
         linkCreator.createLink(jctDir, orgDir);
         // delete
-        cleaner.delete(dirWithLnk.toFile(), null, false, true, false);
+        cleaner.delete(dirWithLnk, null, false, true, false);
         // verify
         assertTrue(Files.exists(file));
         assertFalse(Files.exists(jctDir));
@@ -276,7 +276,7 @@ private void testSymlink(LinkCreator linkCreator) throws Exception {
         Files.write(file, Collections.singleton("Hello world"));
         linkCreator.createLink(jctDir, orgDir);
         // delete
-        cleaner.delete(dirWithLnk.toFile(), null, true, true, false);
+        cleaner.delete(dirWithLnk, null, true, true, false);
         // verify
         assertFalse(Files.exists(file));
         assertFalse(Files.exists(jctDir));