Class FilesystemResourceLoader

  • All Implemented Interfaces:
    ResourceLoader

    public final class FilesystemResourceLoader
    extends java.lang.Object
    implements ResourceLoader
    Simple ResourceLoader that opens resource files from the local file system, optionally resolving against a base directory.

    This loader wraps a delegate ResourceLoader that is used to resolve all files, the current base directory does not contain. newInstance(java.lang.String, java.lang.Class<T>) is always resolved against the delegate, as a ClassLoader is needed.

    You can chain several FilesystemResourceLoaders to allow lookup of files in more than one base directory.

    • Constructor Summary

      Constructors 
      Constructor Description
      FilesystemResourceLoader​(java.nio.file.Path baseDirectory, java.lang.ClassLoader delegate)
      Creates a resource loader that resolves resources against the given base directory.
      FilesystemResourceLoader​(java.nio.file.Path baseDirectory, java.lang.Module delegate)
      Creates a resource loader that resolves resources against the given base directory.
      FilesystemResourceLoader​(java.nio.file.Path baseDirectory, ResourceLoader delegate)
      Creates a resource loader that resolves resources against the given base directory.
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      <T> java.lang.Class<? extends T> findClass​(java.lang.String cname, java.lang.Class<T> expectedType)
      Finds class of the name and expected type
      <T> T newInstance​(java.lang.String cname, java.lang.Class<T> expectedType)
      Creates an instance of the name and expected type
      java.io.InputStream openResource​(java.lang.String resource)
      Opens a named resource
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Field Detail

      • baseDirectory

        private final java.nio.file.Path baseDirectory
    • Constructor Detail

      • FilesystemResourceLoader

        public FilesystemResourceLoader​(java.nio.file.Path baseDirectory,
                                        java.lang.ClassLoader delegate)
        Creates a resource loader that resolves resources against the given base directory. Files not found in file system and class lookups are delegated to ClassLoader.

        To use this constructor with the Java Module System, you must open all modules that contain resources to the org.apache.lucene.core module, otherwise resources can't be looked up. It is recommended to use FilesystemResourceLoader(Path, Module) for such use cases as this would limit to certain modules.

      • FilesystemResourceLoader

        public FilesystemResourceLoader​(java.nio.file.Path baseDirectory,
                                        java.lang.Module delegate)
        Creates a resource loader that resolves resources against the given base directory. Files not found in file system and class lookups are delegated to ModuleResourceLoader.

        To use this constructor, you must open the module to the org.apache.lucene.core module, otherwise resources can't be looked up.

      • FilesystemResourceLoader

        public FilesystemResourceLoader​(java.nio.file.Path baseDirectory,
                                        ResourceLoader delegate)
        Creates a resource loader that resolves resources against the given base directory. Files not found in file system and class lookups are delegated to the given delegate ResourceLoader.
    • Method Detail

      • openResource

        public java.io.InputStream openResource​(java.lang.String resource)
                                         throws java.io.IOException
        Description copied from interface: ResourceLoader
        Opens a named resource
        Specified by:
        openResource in interface ResourceLoader
        Throws:
        java.io.IOException
      • newInstance

        public <T> T newInstance​(java.lang.String cname,
                                 java.lang.Class<T> expectedType)
        Description copied from interface: ResourceLoader
        Creates an instance of the name and expected type
        Specified by:
        newInstance in interface ResourceLoader
      • findClass

        public <T> java.lang.Class<? extends T> findClass​(java.lang.String cname,
                                                          java.lang.Class<T> expectedType)
        Description copied from interface: ResourceLoader
        Finds class of the name and expected type
        Specified by:
        findClass in interface ResourceLoader