Closes #132: Use URL class loader internally

java-compiler-testing/src/main/java/io/github/ascopes/jct/containers/impl/AbstractPackageContainerGroup.java

@@ -52,8 +52,7 @@
  * @since 0.0.1
  */
 @API(since = "0.0.1", status = Status.INTERNAL)
-public abstract class AbstractPackageContainerGroup
-    implements PackageContainerGroup {
+public abstract class AbstractPackageContainerGroup implements PackageContainerGroup {
 
   // https://docs.oracle.com/cd/E19830-01/819-4712/ablgz/index.html
   private static final Set<String> ARCHIVE_EXTENSIONS = Set.of(
@@ -268,8 +267,10 @@ public void listFileObjects(
     }
   }
 
-  protected ContainerGroupClassLoaderImpl createClassLoader() {
-    return new ContainerGroupClassLoaderImpl(getLocation(), getPackages());
-  }
-
+  /**
+   * Create a classloader and return it.
+   *
+   * @return the classloader.
+   */
+  protected abstract ClassLoader createClassLoader();
 }

java-compiler-testing/src/main/java/io/github/ascopes/jct/containers/impl/ContainerGroupClassLoaderImpl.java → java-compiler-testing/src/main/java/io/github/ascopes/jct/containers/impl/ContainerGroupPathClassLoader.java

@@ -40,15 +40,18 @@
  *
  * @author Ashley Scopes
  * @since 0.0.1
+ * @deprecated use {@link ContainerGroupUrlClassLoader} instead. This class is kept for profiling
+ *     later on to compare the performance of the newer URL class loader versus this one.
  */
-@API(since = "0.0.1", status = Status.EXPERIMENTAL)
-public class ContainerGroupClassLoaderImpl extends ClassLoader {
+@API(since = "0.0.1", status = Status.DEPRECATED)
+@Deprecated(forRemoval = true)
+public class ContainerGroupPathClassLoader extends ClassLoader {
 
   static {
     ClassLoader.registerAsParallelCapable();
   }
 
-  private static final Logger LOGGER = LoggerFactory.getLogger(ContainerGroupClassLoaderImpl.class);
+  private static final Logger LOGGER = LoggerFactory.getLogger(ContainerGroupPathClassLoader.class);
   private static final List<Container> NO_PACKAGES = List.of();
   private static final Map<String, ? extends List<Container>> NO_MODULES = Map.of();
 
@@ -62,7 +65,7 @@ public class ContainerGroupClassLoaderImpl extends ClassLoader {
    * @param location          the location that the containers are for.
    * @param packageContainers the package containers.
    */
-  public ContainerGroupClassLoaderImpl(Location location,
+  public ContainerGroupPathClassLoader(Location location,
       List<? extends Container> packageContainers) {
     this(location, packageContainers, NO_MODULES);
   }
@@ -73,7 +76,7 @@ public ContainerGroupClassLoaderImpl(Location location,
    * @param location         the location that the containers are for.
    * @param moduleContainers the module containers.
    */
-  public ContainerGroupClassLoaderImpl(
+  public ContainerGroupPathClassLoader(
       Location location,
       Map<String, ? extends List<Container>> moduleContainers
   ) {
@@ -87,7 +90,7 @@ public ContainerGroupClassLoaderImpl(
    * @param packageContainers the package containers.
    * @param moduleContainers  the module containers.
    */
-  public ContainerGroupClassLoaderImpl(
+  public ContainerGroupPathClassLoader(
       Location location,
       List<? extends Container> packageContainers,
       Map<String, ? extends List<Container>> moduleContainers

java-compiler-testing/src/main/java/io/github/ascopes/jct/containers/impl/ContainerGroupUrlClassLoader.java

@@ -0,0 +1,106 @@
+/*
+ * Copyright (C) 2022 - 2022 Ashley Scopes
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.github.ascopes.jct.containers.impl;
+
+import io.github.ascopes.jct.containers.Container;
+import io.github.ascopes.jct.containers.ModuleContainerGroup;
+import io.github.ascopes.jct.containers.OutputContainerGroup;
+import io.github.ascopes.jct.containers.PackageContainerGroup;
+import io.github.ascopes.jct.pathwrappers.PathWrapper;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.util.Collection;
+import java.util.stream.Stream;
+import org.apiguardian.api.API;
+import org.apiguardian.api.API.Status;
+
+/**
+ * An extension of the Java {@link URLClassLoader} that wraps around container groups.
+ *
+ * @author Ashley Scopes
+ * @since 0.0.1
+ */
+@API(since = "0.0.1", status = Status.INTERNAL)
+public final class ContainerGroupUrlClassLoader extends URLClassLoader {
+
+  private ContainerGroupUrlClassLoader(String name, URL[] urls) {
+    super(name, urls, ClassLoader.getSystemClassLoader());
+  }
+
+  /**
+   * Create a class loader for a given package container group.
+   *
+   * @param group the package container group to wrap.
+   * @return the class loader.
+   */
+  public static ContainerGroupUrlClassLoader createClassLoaderFor(PackageContainerGroup group) {
+    return new ContainerGroupUrlClassLoader(
+        "Packages within package group " + group.getLocation().getName(),
+        urlsForPackageGroup(group)
+            .distinct()
+            .toArray(URL[]::new)
+    );
+  }
+
+  /**
+   * Create a class loader for a given module container group.
+   *
+   * @param group the module container group to wrap.
+   * @return the class loader.
+   */
+  public static ContainerGroupUrlClassLoader createClassLoaderFor(ModuleContainerGroup group) {
+    return new ContainerGroupUrlClassLoader(
+        "Packages within module group " + group.getLocation().getName(),
+        urlsForModuleGroup(group)
+            .distinct()
+            .toArray(URL[]::new)
+    );
+  }
+
+  /**
+   * Create a class loader for a given output container group.
+   *
+   * @param group the output container group to wrap.
+   * @return the class loader.
+   */
+  public static ContainerGroupUrlClassLoader createClassLoaderFor(OutputContainerGroup group) {
+    return new ContainerGroupUrlClassLoader(
+        "Packages within output group " + group.getLocation().getName(),
+        Stream.concat(urlsForPackageGroup(group), urlsForModuleGroup(group))
+            .distinct()
+            .toArray(URL[]::new)
+    );
+  }
+
+  private static Stream<URL> urlsForPackageGroup(PackageContainerGroup group) {
+    return group
+        .getPackages()
+        .stream()
+        .map(Container::getPathWrapper)
+        .map(PathWrapper::getUrl);
+  }
+
+  private static Stream<URL> urlsForModuleGroup(ModuleContainerGroup group) {
+    return group
+        .getModules()
+        .values()
+        .stream()
+        .map(PackageContainerGroup::getPackages)
+        .flatMap(Collection::stream)
+        .map(Container::getPathWrapper)
+        .map(PathWrapper::getUrl);
+  }
+}

java-compiler-testing/src/main/java/io/github/ascopes/jct/containers/impl/ModuleContainerGroupImpl.java

@@ -37,7 +37,6 @@
 import java.util.Map;
 import java.util.ServiceLoader;
 import java.util.Set;
-import java.util.stream.Collectors;
 import javax.tools.JavaFileManager.Location;
 import org.apiguardian.api.API;
 import org.apiguardian.api.API.Status;
@@ -54,7 +53,7 @@ public final class ModuleContainerGroupImpl implements ModuleContainerGroup {
   private final Location location;
   private final Map<ModuleLocation, @WillCloseWhenClosed ModulePackageContainerGroupImpl> modules;
   private final String release;
-  private final Lazy<ContainerGroupClassLoaderImpl> classLoaderLazy;
+  private final Lazy<ClassLoader> classLoaderLazy;
 
   /**
    * Initialize this container group.
@@ -207,16 +206,8 @@ public String toString() {
         .toString();
   }
 
-  private ContainerGroupClassLoaderImpl createClassLoader() {
-    var moduleMapping = modules
-        .entrySet()
-        .stream()
-        .collect(Collectors.toUnmodifiableMap(
-            entry -> entry.getKey().getModuleName(),
-            entry -> entry.getValue().getPackages()
-        ));
-
-    return new ContainerGroupClassLoaderImpl(location, moduleMapping);
+  private ClassLoader createClassLoader() {
+    return ContainerGroupUrlClassLoader.createClassLoaderFor(this);
   }
 
   private ModulePackageContainerGroupImpl newPackageGroup(ModuleLocation location) {
@@ -233,5 +224,10 @@ private static final class ModulePackageContainerGroupImpl
     private ModulePackageContainerGroupImpl(ModuleLocation location, String release) {
       super(location, release);
     }
+
+    @Override
+    protected ClassLoader createClassLoader() {
+      return ContainerGroupUrlClassLoader.createClassLoaderFor(this);
+    }
   }
 }

java-compiler-testing/src/main/java/io/github/ascopes/jct/containers/impl/OutputContainerGroupImpl.java

@@ -34,7 +34,6 @@
 import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
-import java.util.stream.Collectors;
 import javax.tools.JavaFileManager.Location;
 import javax.tools.JavaFileObject.Kind;
 import org.apiguardian.api.API;
@@ -213,7 +212,7 @@ public List<Set<Location>> getLocationsForModules() {
 
   @Override
   public Map<ModuleLocation, PackageContainerGroup> getModules() {
-    return null;
+    return Map.copyOf(modules);
   }
 
   @Override
@@ -227,16 +226,8 @@ public boolean hasLocation(ModuleLocation location) {
   }
 
   @Override
-  protected ContainerGroupClassLoaderImpl createClassLoader() {
-    var moduleMapping = modules
-        .entrySet()
-        .stream()
-        .collect(Collectors.toUnmodifiableMap(
-            entry -> entry.getKey().getModuleName(),
-            entry -> entry.getValue().getPackages()
-        ));
-
-    return new ContainerGroupClassLoaderImpl(location, getPackages(), moduleMapping);
+  protected ClassLoader createClassLoader() {
+    return ContainerGroupUrlClassLoader.createClassLoaderFor(this);
   }
 
   @SuppressWarnings("resource")
@@ -267,5 +258,10 @@ private static final class OutputPackageContainerGroupImpl
     private OutputPackageContainerGroupImpl(Location location, String release) {
       super(location, release);
     }
+
+    @Override
+    protected ClassLoader createClassLoader() {
+      return ContainerGroupUrlClassLoader.createClassLoaderFor(this);
+    }
   }
 }

java-compiler-testing/src/main/java/io/github/ascopes/jct/containers/impl/PackageContainerGroupImpl.java

@@ -59,4 +59,9 @@ public PackageContainerGroupImpl(Location location, String release) {
       );
     }
   }
+
+  @Override
+  protected ClassLoader createClassLoader() {
+    return ContainerGroupUrlClassLoader.createClassLoaderFor(this);
+  }
 }

java-compiler-testing/src/main/java/io/github/ascopes/jct/pathwrappers/AbstractTestDirectory.java

@@ -21,6 +21,7 @@
 import io.github.ascopes.jct.annotations.CheckReturnValue;
 import io.github.ascopes.jct.annotations.Nullable;
 import io.github.ascopes.jct.annotations.WillClose;
+import io.github.ascopes.jct.pathwrappers.impl.PathWrapperUtils;
 import io.github.ascopes.jct.utils.GarbageDisposalUtils;
 import io.github.ascopes.jct.utils.ToStringBuilder;
 import java.io.BufferedInputStream;
@@ -72,6 +73,7 @@ public abstract class AbstractTestDirectory<I extends AbstractTestDirectory<I>>
   private final Path rootDirectory;
   private final String separator;
   private final URI uri;
+  private final URL url;
   private final Closeable closeHook;
 
   @SuppressWarnings("ThisEscapedInObjectConstruction")
@@ -82,16 +84,19 @@ protected AbstractTestDirectory(
       boolean closeOnGc,
       Closeable closeHook
   ) {
+
+    // Register immediately so we still clean up if an exception is thrown from this constructor.
+    if (closeOnGc) {
+      LOGGER.trace("Registering {} to be destroyed on garbage collection", rootDirectory.toUri());
+      GarbageDisposalUtils.onPhantom(this, name, closeHook);
+    }
+
     this.name = requireNonNull(name, "name");
     this.closeHook = requireNonNull(closeHook, "closeHook");
     this.rootDirectory = requireNonNull(rootDirectory, "rootDirectory");
     this.separator = requireNonNull(separator, "separator");
     uri = this.rootDirectory.toUri();
-
-    if (closeOnGc) {
-      LOGGER.trace("Registering {} to be destroyed on garbage collection", uri);
-      GarbageDisposalUtils.onPhantom(this, name, closeHook);
-    }
+    url = PathWrapperUtils.retrieveRequiredUrl(this.rootDirectory);
   }
 
 
@@ -119,6 +124,12 @@ public URI getUri() {
     return uri;
   }
 
+  @CheckReturnValue
+  @Override
+  public URL getUrl() {
+    return url;
+  }
+
   /**
    * Get the identifying name of the temporary file system.
    *
@@ -297,31 +308,6 @@ private I thisTestFileSystem() {
     return (I) this;
   }
 
-  /**
-   * Assert that the given name is a valid name for a directory, and that it does not contain
-   * potentially dangerous characters such as double-dots or slashes that could be used to escape
-   * the directory we are running from.
-   *
-   * @param name the directory name to check.
-   * @throws IllegalArgumentException if the name is invalid.
-   * @throws NullPointerException     if the name is {@code null}.
-   */
-  protected static void assertValidRootName(@Nullable String name) {
-    Objects.requireNonNull(name, "name");
-
-    if (name.isBlank()) {
-      throw new IllegalArgumentException("Directory name cannot be blank");
-    }
-
-    if (!name.equals(name.trim())) {
-      throw new IllegalArgumentException("Directory name cannot begin or end in spaces");
-    }
-
-    if (name.contains("/") || name.contains("\\") || name.contains("..")) {
-      throw new IllegalArgumentException("Invalid file name provided");
-    }
-  }
-
   /**
    * Chainable builder for creating individual files.
    *

java-compiler-testing/src/main/java/io/github/ascopes/jct/pathwrappers/PathWrapper.java

@@ -17,6 +17,7 @@
 
 import io.github.ascopes.jct.annotations.Nullable;
 import java.net.URI;
+import java.net.URL;
 import java.nio.file.FileSystem;
 import java.nio.file.Path;
 import org.apiguardian.api.API;
@@ -60,6 +61,13 @@ public interface PathWrapper {
    */
   URI getUri();
 
+  /**
+   * Get a URL representation of this path-like object.
+   *
+   * @return the URL.
+   */
+  URL getUrl();
+
   /**
    * Get the parent path wrapper, if there is one.
    *