SJH 3.0: Replace BiPredicate by UnionPathFilter in UnionFS and hide S…

…ecureJar impl details

src/main/java/cpw/mods/jarhandling/JarContentsBuilder.java

@@ -53,6 +53,6 @@ public JarContentsBuilder pathFilter(@Nullable UnionPathFilter pathFilter) {
      * Builds the jar.
      */
     public JarContents build() {
-        return new JarContentsImpl(paths, defaultManifest, pathFilter == null ? null : pathFilter::test);
+        return new JarContentsImpl(paths, defaultManifest, pathFilter);
     }
 }

src/main/java/cpw/mods/jarhandling/SecureJar.java

@@ -138,7 +138,7 @@ record Provider(String serviceName, List<String> providers) {
         /**
          * Helper method to parse service provider implementations from a {@link Path}.
          */
-        public static Provider fromPath(final Path path, final UnionPathFilter pkgFilter) {
+        public static Provider fromPath(Path path, @Nullable UnionPathFilter pkgFilter) {
             final var sname = path.getFileName().toString();
             try {
                 var entries = Files.readAllLines(path).stream()

src/main/java/cpw/mods/niofs/union/UnionFileSystem.java

@@ -31,12 +31,17 @@
 import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
+import java.util.Spliterator;
+import java.util.Spliterators;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 import java.util.stream.IntStream;
 import java.util.stream.Stream;
 import java.util.stream.StreamSupport;
 
+/**
+ * Can be instantiated using the public methods in {@link UnionFileSystemProvider}.
+ */
 public class UnionFileSystem extends FileSystem {
     private static final MethodHandle ZIPFS_CH;
     private static final MethodHandle FCI_UNINTERUPTIBLE;
@@ -83,7 +88,7 @@ private static class UncheckedIOException extends java.io.UncheckedIOException {
         public UncheckedIOException(final IOException cause) {
             super(cause);
         }
-        
+
         public UncheckedIOException(final String message, final IOException cause) {
             super(message, cause);
         }
@@ -107,6 +112,9 @@ public Path getPrimaryPath() {
         return basepaths.get(basepaths.size() - 1);
     }
 
+    /**
+     * {@return the filter for this file system, or null if there is none}
+     */
     @Nullable
     public UnionPathFilter getFilesystemFilter() {
         return pathFilter;
@@ -119,7 +127,7 @@ String getKey() {
     private record EmbeddedFileSystemMetadata(Path path, FileSystem fs, SeekableByteChannel fsCh) {
     }
 
-    public UnionFileSystem(final UnionFileSystemProvider provider, @Nullable UnionPathFilter pathFilter, final String key, final Path... basepaths) {
+    UnionFileSystem(UnionFileSystemProvider provider, @Nullable UnionPathFilter pathFilter, String key, Path... basepaths) {
         this.pathFilter = pathFilter;
         this.provider = provider;
         this.key = key;

src/main/java/cpw/mods/niofs/union/UnionFileSystemProvider.java

@@ -29,7 +29,6 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
-import java.util.function.BiPredicate;
 import java.util.stream.Stream;
 
 public class UnionFileSystemProvider extends FileSystemProvider {
@@ -73,24 +72,7 @@ protected Path uriToPath(URI uri) {
      */
     @Override
     public FileSystem newFileSystem(final URI uri, final Map<String, ?> env) throws IOException {
-        @SuppressWarnings("unchecked")
-        var additional = ((Map<String, List<Path>>)env).getOrDefault("additional", List.<Path>of());
-        @SuppressWarnings("unchecked")
-        var filter = ((Map<String, UnionPathFilter>)env).getOrDefault("filter", null);
-
-        if (filter == null && additional.isEmpty())
-            throw new IllegalArgumentException("Missing additional and/or filter");
-
-        if (filter == null)
-            filter = (p, b) -> true;
-
-        var path = uriToPath(uri);
-        var key = makeKey(path);
-        try {
-            return newFileSystemInternal(key, filter, Stream.concat(Stream.of(path), additional.stream()).toArray(Path[]::new));
-        } catch (UncheckedIOException e) {
-            throw e.getCause();
-        }
+        return newFileSystem(uriToPath(uri), env);
     }
 
     /**
@@ -105,8 +87,7 @@ public FileSystem newFileSystem(final URI uri, final Map<String, ?> env) throws
     public FileSystem newFileSystem(final Path path, final Map<String, ?> env) throws IOException {
         @SuppressWarnings("unchecked")
         var additional = ((Map<String, List<Path>>)env).getOrDefault("additional", List.<Path>of());
-        @SuppressWarnings("unchecked")
-        var filter = ((Map<String, UnionPathFilter>)env).getOrDefault("filter", null);
+        var filter = readFilterFromEnv(env);
 
         if (filter == null && additional.isEmpty())
             throw new UnsupportedOperationException("Missing additional and/or filter");
@@ -119,6 +100,19 @@ public FileSystem newFileSystem(final Path path, final Map<String, ?> env) throw
         }
     }
 
+    @Nullable
+    private static UnionPathFilter readFilterFromEnv(Map<String, ?> env) {
+        Object filter = env.get("filter");
+
+        if (filter == null) {
+            return null;
+        } else if (filter instanceof UnionPathFilter unionPathFilter) {
+            return unionPathFilter;
+        } else {
+            throw new IllegalArgumentException("Unknown type for \"filter\" UnionFileSystem env var: " + filter.getClass().getName());
+        }
+    }
+
     public UnionFileSystem newFileSystem(@Nullable UnionPathFilter pathfilter, final Path... paths) {
         if (paths.length == 0) throw new IllegalArgumentException("Need at least one path");
         var key = makeKey(paths[0]);

src/main/java/module-info.java

@@ -3,7 +3,6 @@
 
 module cpw.mods.securejarhandler {
     exports cpw.mods.jarhandling;
-    exports cpw.mods.jarhandling.impl; // TODO - Bump version, and remove this export, you don't need our implementation
     exports cpw.mods.cl;
     exports cpw.mods.niofs.union;
     requires jdk.unsupported;