Add support for symbolic links in ZIP file resource collections

Author: plamentotev

src/main/java/org/codehaus/plexus/archiver/zip/PlexusArchiverZipFileResourceCollection.java

@@ -57,7 +57,9 @@ public PlexusIoResource next()
         {
             final ZipArchiveEntry entry = (ZipArchiveEntry) en.nextElement();
 
-            return new ZipResource( zipFile, entry, getStreamTransformer() );
+            return !entry.isUnixSymlink()
+                ? new ZipResource( zipFile, entry, getStreamTransformer() )
+                : new ZipSymlinkResource( zipFile, entry, getStreamTransformer() );
         }
 
         public void remove()

src/main/java/org/codehaus/plexus/archiver/zip/ZipSymlinkResource.java

@@ -0,0 +1,41 @@
+package org.codehaus.plexus.archiver.zip;
+
+import java.io.IOException;
+
+import org.apache.commons.compress.archivers.zip.ZipArchiveEntry;
+import org.apache.commons.compress.archivers.zip.ZipFile;
+import org.codehaus.plexus.components.io.functions.InputStreamTransformer;
+import org.codehaus.plexus.components.io.functions.SymlinkDestinationSupplier;
+
+/**
+ * A {@link ZipResource} that represents symbolic link.
+ */
+public class ZipSymlinkResource
+    extends ZipResource
+    implements SymlinkDestinationSupplier
+{
+    private final String symlinkDestination;
+
+    public ZipSymlinkResource(ZipFile zipFile, ZipArchiveEntry entry, InputStreamTransformer streamTransformer)
+    {
+        super(zipFile, entry, streamTransformer);
+        try {
+            symlinkDestination = zipFile.getUnixSymlink(entry);
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    @Override
+    public String getSymlinkDestination() throws IOException
+    {
+        return symlinkDestination;
+    }
+
+    @Override
+    public boolean isSymbolicLink()
+    {
+        return true;
+    }
+
+}

src/test/java/org/codehaus/plexus/archiver/zip/ZipArchiverTest.java

@@ -533,6 +533,20 @@ public void testSymlinkFileSet()
         assertTrue( fa.isSymbolicLink() );
     }
 
+    public void testSymlinkArchivedFileSet()
+        throws Exception
+    {
+        final File zipFile = getTestFile( "src/test/resources/symlinks/symlinks.zip" );
+        final File zipFile2 = getTestFile( "target/output/pasymlinks-archivedFileset.zip" );
+        final ZipArchiver zipArchiver = getZipArchiver( zipFile2 );
+        zipArchiver.addArchivedFileSet( zipFile );
+        zipArchiver.createArchive();
+
+        final ZipFile cmp1 = new ZipFile( zipFile );
+        final ZipFile cmp2 = new ZipFile( zipFile2 );
+        ArchiveFileComparator.assertEquals( cmp1, cmp2, "" );
+    }
+
     /*
      */