Package org.eclipse.jetty.util.resource

Class Resource

java.lang.Object
org.eclipse.jetty.util.resource.Resource
All Implemented Interfaces:
Closeable, AutoCloseable, ResourceFactory
Direct Known Subclasses:
EmptyResource, PathResource, ResourceCollection, URLResource
public abstract class Resource extends Object implements ResourceFactory, Closeable
Abstract resource class.

This class provides a resource abstraction, where a resource may be a file, a URL or an entry in a jar file.

  • Field Details

    • __defaultUseCaches

      public static boolean __defaultUseCaches

  • Constructor Details

    • Resource

      public Resource()

  • Method Details

    • setDefaultUseCaches

      public static void setDefaultUseCaches(boolean useCaches)
      Change the default setting for url connection caches. Subsequent URLConnections will use this default.
      Parameters:
      useCaches - true to enable URL connection caches, false otherwise.

    • getDefaultUseCaches

      public static boolean getDefaultUseCaches()

    • resolveAlias

      public static Resource resolveAlias(Resource resource)
      Attempt to resolve the real path of a Resource to potentially remove any symlinks causing the Resource to be an alias.
      Parameters:
      resource - the resource to resolve.
      Returns:
      a new Resource resolved to the real path of the original Resource, or the original resource if it was not an alias.

    • newResource

      public static Resource newResource(URI uri) throws MalformedURLException
      Construct a resource from a uri.
      Parameters:
      uri - A URI.
      Returns:
      A Resource object.
      Throws:
      MalformedURLException - Problem accessing URI

    • newResource

      public static Resource newResource(URL url)
      Construct a resource from a url.
      Parameters:
      url - A URL.
      Returns:
      A Resource object.

    • newResource

      public static Resource newResource(String resource) throws IOException
      Construct a resource from a string.
      Parameters:
      resource - A URL or filename.
      Returns:
      A Resource object.
      Throws:
      MalformedURLException - Problem accessing URI
      IOException

    • newResource

      public static Resource newResource(String resource, boolean useCaches) throws IOException
      Construct a resource from a string.
      Parameters:
      resource - A URL or filename.
      useCaches - controls URLConnection caching
      Returns:
      A Resource object.
      Throws:
      MalformedURLException - Problem accessing URI
      IOException

    • newResource

      public static Resource newResource(File file)

    • newResource

      public static Resource newResource(Path path)
      Construct a Resource from provided path
      Parameters:
      path - the path
      Returns:
      the Resource for the provided path
      Since:
      9.4.10

    • newSystemResource

      public static Resource newSystemResource(String resource) throws IOException
      Construct a system resource from a string. The resource is tried as classloader resource before being treated as a normal resource.
      Parameters:
      resource - Resource as string representation
      Returns:
      The new Resource
      Throws:
      IOException - Problem accessing resource.

    • newClassPathResource

      public static Resource newClassPathResource(String resource)
      Find a classpath resource.
      Parameters:
      resource - the relative name of the resource
      Returns:
      Resource or null

    • newClassPathResource

      public static Resource newClassPathResource(String name, boolean useCaches, boolean checkParents)
      Find a classpath resource. The Class.getResource(String) method is used to lookup the resource. If it is not found, then the Loader.getResource(String) method is used. If it is still not found, then ClassLoader.getSystemResource(String) is used. Unlike ClassLoader.getSystemResource(String) this method does not check for normal resources.
      Parameters:
      name - The relative name of the resource
      useCaches - True if URL caches are to be used.
      checkParents - True if forced searching of parent Classloaders is performed to work around loaders with inverted priorities
      Returns:
      Resource or null

    • isContainedIn

      public static boolean isContainedIn(Resource r, Resource containingResource) throws MalformedURLException
      Throws:
      MalformedURLException

    • isContainedIn

      public abstract boolean isContainedIn(Resource r) throws MalformedURLException
      Throws:
      MalformedURLException

    • isSame

      public boolean isSame(Resource resource)
      Return true if the passed Resource represents the same resource as the Resource. For many resource types, this is equivalent to Object.equals(Object), however for resources types that support aliasing, this maybe some other check (e.g. Files.isSameFile(Path, Path)).
      Parameters:
      resource - The resource to check
      Returns:
      true if the passed resource represents the same resource.

    • close

      public abstract void close()
      Release any temporary resources held by the resource.
      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable

    • exists

      public abstract boolean exists()
      Returns:
      true if the represented resource exists.

    • isDirectory

      public abstract boolean isDirectory()
      Returns:
      true if the represented resource is a container/directory.

    • lastModified

      public abstract long lastModified()
      Time resource was last modified.
      Returns:
      the last modified time as milliseconds since unix epoch

    • length

      public abstract long length()
      Length of the resource.
      Returns:
      the length of the resource

    • getURI

      public abstract URI getURI()
      URI representing the resource.
      Returns:
      an URI representing the given resource

    • getFile

      public abstract File getFile() throws IOException
      File representing the given resource.
      Returns:
      an File representing the given resource or NULL if this is not possible.
      Throws:
      IOException - if unable to get the resource due to permissions

    • getName

      public abstract String getName()
      The name of the resource.
      Returns:
      the name of the resource

    • getInputStream

      public abstract InputStream getInputStream() throws IOException
      Input stream to the resource
      Returns:
      an input stream to the resource
      Throws:
      IOException - if unable to open the input stream

    • getReadableByteChannel

      public abstract ReadableByteChannel getReadableByteChannel() throws IOException
      Readable ByteChannel for the resource.
      Returns:
      an readable bytechannel to the resource or null if one is not available.
      Throws:
      IOException - if unable to open the readable bytechannel for the resource.

    • delete

      public abstract boolean delete() throws SecurityException
      Deletes the given resource
      Returns:
      true if resource was found and successfully deleted, false if resource didn't exist or was unable to be deleted.
      Throws:
      SecurityException - if unable to delete due to permissions

    • renameTo

      public abstract boolean renameTo(Resource dest) throws SecurityException
      Rename the given resource
      Parameters:
      dest - the destination name for the resource
      Returns:
      true if the resource was renamed, false if the resource didn't exist or was unable to be renamed.
      Throws:
      SecurityException - if unable to rename due to permissions

    • list

      public abstract String[] list()
      list of resource names contained in the given resource. Ordering is unspecified, so callers may wish to sort the return value to ensure deterministic behavior.
      Returns:
      a list of resource names contained in the given resource, or null. Note: The resource names are not URL encoded.

    • addPath

      public abstract Resource addPath(String path) throws IOException, MalformedURLException
      Returns the resource contained inside the current resource with the given name, which may or may not exist.
      Parameters:
      path - The path segment to add, which is not encoded. The path may be non canonical, but if so then the resulting Resource will return true from isAlias().
      Returns:
      the Resource for the resolved path within this Resource, never null
      Throws:
      IOException - if unable to resolve the path
      MalformedURLException - if the resolution of the path fails because the input path parameter is malformed, or a relative path attempts to access above the root resource.

    • getResource

      public Resource getResource(String path) throws IOException
      Get a resource from within this resource.
      Specified by:
      getResource in interface ResourceFactory
      Parameters:
      path - The path to the resource
      Returns:
      The resource, that might not actually exist (yet).
      Throws:
      IOException - if unable to create Resource

    • getAssociate

      public Object getAssociate()

    • setAssociate

      public void setAssociate(Object o)

    • isAlias

      public boolean isAlias()
      Returns:
      true if this Resource is an alias to another real Resource

    • getAlias

      public URI getAlias()
      Returns:
      The canonical Alias of this resource or null if none.

    • getListHTML

      public String getListHTML(String base, boolean parent, String query) throws IOException
      Get the resource list as a HTML directory listing.
      Parameters:
      base - The base URL
      parent - True if the parent directory should be included
      query - query params
      Returns:
      String of HTML
      Throws:
      IOException - on failure to generate a list.

    • copyTo

      public void copyTo(File destination) throws IOException
      Copy the Resource to the new destination file.

      Will not replace existing destination file.

      Parameters:
      destination - the destination file to create
      Throws:
      IOException - if unable to copy the resource

    • getWeakETag

      public String getWeakETag()
      Generate a weak ETag reference for this Resource.
      Returns:
      the weak ETag reference for this resource.

    • getWeakETag

      public String getWeakETag(String suffix)

    • getAllResources

      public Collection<Resource> getAllResources()

    • toURL

      public static URL toURL(File file) throws MalformedURLException
      Generate a properly encoded URL from a File instance.
      Parameters:
      file - Target file.
      Returns:
      URL of the target file.
      Throws:
      MalformedURLException - if unable to convert File to URL

    • fromList

      public static List<Resource> fromList(String resources, boolean globDirs) throws IOException
      Parse a list of String delimited resources and return the List of Resources instances it represents.

      Supports glob references that end in /* or \*. Glob references will only iterate through the level specified and will not traverse found directories within the glob reference.

      Parameters:
      resources - the comma , or semicolon ; delimited String of resource references.
      globDirs - true to return directories in addition to files at the level of the glob
      Returns:
      the list of resources parsed from input string.
      Throws:
      IOException

    • fromList

      public static List<Resource> fromList(String resources, boolean globDirs, ResourceFactory resourceFactory) throws IOException
      Parse a delimited String of resource references and return the List of Resources instances it represents.

      Supports glob references that end in /* or \*. Glob references will only iterate through the level specified and will not traverse found directories within the glob reference.

      Parameters:
      resources - the comma , or semicolon ; delimited String of resource references.
      globDirs - true to return directories in addition to files at the level of the glob
      resourceFactory - the ResourceFactory used to create new Resource references
      Returns:
      the list of resources parsed from input string.
      Throws:
      IOException