src/java.base/share/classes/jdk/internal/jrtfs/SystemImage.java

@@ -37,47 +37,62 @@
  import java.security.CodeSource;
  import java.security.PrivilegedAction;
  
  import jdk.internal.jimage.ImageReader;
  import jdk.internal.jimage.ImageReader.Node;
+ import jdk.internal.jimage.PreviewMode;
  
  /**
   * @implNote This class needs to maintain JDK 8 source compatibility.
   *
   * It is used internally in the JDK to implement jimage/jrtfs access,
   * but also compiled and delivered as part of the jrtfs.jar to support access
   * to the jimage file provided by the shipped JDK by tools running on JDK 8.
   */
- @SuppressWarnings({ "removal", "suppression"} )
- abstract class SystemImage {
+ @SuppressWarnings({"removal", "suppression"})
+ public abstract class SystemImage implements AutoCloseable {
  
-     abstract Node findNode(String path) throws IOException;
-     abstract byte[] getResource(Node node) throws IOException;
-     abstract void close() throws IOException;
+     public abstract Node findNode(String path) throws IOException;
+     public abstract byte[] getResource(Node node) throws IOException;
+     public abstract void close() throws IOException;
  
-     static SystemImage open() throws IOException {
-         if (modulesImageExists) {
-             // open a .jimage and build directory structure
-             final ImageReader image = ImageReader.open(moduleImageFile);
-             return new SystemImage() {
-                 @Override
-                 Node findNode(String path) throws IOException {
-                     return image.findNode(path);
-                 }
-                 @Override
-                 byte[] getResource(Node node) throws IOException {
-                     return image.getResource(node);
-                 }
-                 @Override
-                 void close() throws IOException {
-                     image.close();
-                 }
-             };
+     /**
+      * Opens the system image for the current runtime.
+      *
+      * @param mode determines whether preview mode should be enabled.
+      * @return a new system image based on either the jimage file or an "exploded"
+      *     modules directory, according to the build state.
+      */
+     public static SystemImage open(PreviewMode mode) throws IOException {
+         return modulesImageExists ? fromJimage(moduleImageFile, mode) : fromDirectory(explodedModulesDir, mode);
+     }
+ 
+     /** Internal factory method for testing only, use {@link SystemImage#open(PreviewMode)}. */
+     public static SystemImage fromJimage(Path path, PreviewMode mode) throws IOException {
+         final ImageReader image = ImageReader.open(path, mode);
+         return new SystemImage() {
+             @Override
+             public Node findNode(String path) throws IOException {
+                 return image.findNode(path);
+             }
+             @Override
+             public byte[] getResource(Node node) throws IOException {
+                 return image.getResource(node);
+             }
+             @Override
+             public void close() throws IOException {
+                 image.close();
+             }
+         };
+     }
+ 
+     /** Internal factory method for testing only, use {@link SystemImage#open(PreviewMode)}. */
+     public static SystemImage fromDirectory(Path modulesDir, PreviewMode mode) throws IOException {
+         if (!Files.isDirectory(modulesDir)) {
+             throw new FileSystemNotFoundException(modulesDir.toString());
          }
-         if (Files.notExists(explodedModulesDir))
-             throw new FileSystemNotFoundException(explodedModulesDir.toString());
-         return new ExplodedImage(explodedModulesDir);
+         return new ExplodedImage(modulesDir, mode.isPreviewModeEnabled());
      }
  
      private static final String RUNTIME_HOME;
      // "modules" jimage file Path
      private static final Path moduleImageFile;