Package net.shibboleth.shared.spring.resource

Class ConditionalResource

java.lang.Object
net.shibboleth.shared.component.AbstractInitializableComponent
net.shibboleth.shared.component.AbstractIdentifiedInitializableComponent
net.shibboleth.shared.spring.resource.ConditionalResource
All Implemented Interfaces:
Component, DestructableComponent, IdentifiedComponent, InitializableComponent, Resource, Aware, BeanNameAware, InputStreamSource, Resource
public class ConditionalResource extends AbstractIdentifiedInitializableComponent implements Resource, BeanNameAware, Resource
A wrapper that guards a Resource that may be absent by returning an empty bean file instead.
Since:
5.4.0

  • Field Details

    • DEFAULT_CONTENT

      @Nonnull @NotEmpty private static final String DEFAULT_CONTENT
      Dummy content.
      See Also:

    • log

      @Nonnull private final org.slf4j.Logger log
      Logger.

    • logPrefix

      @Nullable private String logPrefix
      Cached log prefix.

    • wrappedResource

      @Nonnull private final Resource wrappedResource
      Resource to wrap.

    • defaultContent

      @NonnullAfterInit private String defaultContent
      Content to return if the resource is missing.

  • Constructor Details

    • ConditionalResource

      public ConditionalResource(@Nonnull Resource wrapped)
      Constructor.
      Parameters:
      wrapped - the resource to wrap

  • Method Details

    • setId

      public void setId(@Nonnull @NotEmpty String id)
      Sets the ID of this component. The component must not yet be initialized. NOTE - this declaration makes the method public
      Overrides:
      setId in class AbstractIdentifiedInitializableComponent
      Parameters:
      id - ID of the component

    • setDefaultContent

      public void setDefaultContent(@Nonnull String content)
      Set the default content to return if the underlying resource is absent.
      Parameters:
      content - default "empty" content
      Since:
      6.1.0

    • getInputStream

      @Nonnull public InputStream getInputStream() throws IOException
      Return an InputStream.

      It is expected that each call creates a fresh stream.

      This requirement is particularly important when you consider an API such as JavaMail, which needs to be able to read the stream multiple times when creating mail attachments. For such a use case, it is required that each getInputStream() call returns a fresh stream.

      Specified by:
      getInputStream in interface InputStreamSource
      Specified by:
      getInputStream in interface Resource
      Returns:
      the input stream for the underlying resource (must not be null)
      Throws:
      IOException - if the stream could not be opened

    • createRelativeResource

      @Nonnull public Resource createRelativeResource(@Nonnull String relativePath) throws IOException
      Create a resource relative to this resource.
      Specified by:
      createRelativeResource in interface Resource
      Parameters:
      relativePath - the relative path (relative to this resource)
      Returns:
      the resource handle for the relative resource
      Throws:
      IOException - if the relative resource cannot be determined

    • setBeanName

      public void setBeanName(@Nonnull String name)
      Specified by:
      setBeanName in interface BeanNameAware

    • exists

      public boolean exists()
      Return whether this resource actually exists in physical form.

      This method performs a definitive existence check, whereas the existence of a Resource handle only guarantees a valid descriptor handle.

      Specified by:
      exists in interface Resource
      Specified by:
      exists in interface Resource
      Returns:
      whether this resource actually exists in physical form.

    • isFile

      public boolean isFile()
      Determine whether this resource represents a file in a file system.

      A value of true strongly suggests (but does not guarantee) that a Resource.getFile() call will succeed.

      This is conservatively false by default.

      Specified by:
      isFile in interface Resource
      Specified by:
      isFile in interface Resource
      Returns:
      true iff this resource represents a file in a file system

    • isReadable

      public boolean isReadable()
      Return whether the contents of this resource can be read, e.g. via Resource.getInputStream() or Resource.getFile().

      Will be true for typical resource descriptors; note that actual content reading may still fail when attempted. However, a value of false is a definitive indication that the resource content cannot be read.

      Specified by:
      isReadable in interface Resource
      Specified by:
      isReadable in interface Resource
      Returns:
      whether the contents of this resource can be read.
      See Also:

    • isOpen

      public boolean isOpen()
      Return whether this resource represents a handle with an open stream. If true, the InputStream cannot be read multiple times, and must be read and closed to avoid resource leaks.

      Will be false for typical resource descriptors.

      Specified by:
      isOpen in interface Resource
      Specified by:
      isOpen in interface Resource
      Returns:
      whether this resource represents a handle with an open stream.

    • getURL

      @Nonnull public URL getURL() throws IOException
      Return a URL handle for this resource.
      Specified by:
      getURL in interface Resource
      Specified by:
      getURL in interface Resource
      Returns:
      a URL handle for this resource.
      Throws:
      IOException - if the resource cannot be resolved as URL, i.e. if the resource is not available as descriptor

    • getURI

      @Nonnull public URI getURI() throws IOException
      Return a URI handle for this resource.
      Specified by:
      getURI in interface Resource
      Specified by:
      getURI in interface Resource
      Returns:
      a URI handle for this resource.
      Throws:
      IOException - if the resource cannot be resolved as URI, i.e. if the resource is not available as descriptor

    • getFile

      @Nonnull public File getFile() throws IOException
      Return a File handle for this resource.
      Specified by:
      getFile in interface Resource
      Specified by:
      getFile in interface Resource
      Returns:
      a File handle for this resource.
      Throws:
      IOException - if the resource cannot be resolved as absolute file path, i.e. if the resource is not available in a file system

    • contentLength

      public long contentLength() throws IOException
      Determine the content length for this resource.
      Specified by:
      contentLength in interface Resource
      Specified by:
      contentLength in interface Resource
      Returns:
      the content length for this resource.
      Throws:
      IOException - if the resource cannot be resolved (in the file system or as some other known physical resource type)

    • lastModified

      public long lastModified() throws IOException
      Determine the last-modified timestamp for this resource.
      Specified by:
      lastModified in interface Resource
      Specified by:
      lastModified in interface Resource
      Returns:
      the last-modified timestamp for this resource.
      Throws:
      IOException - if the resource cannot be resolved (in the file system or as some other known physical resource type)

    • createRelative

      @Nonnull public Resource createRelative(@Nonnull String relativePath) throws IOException
      Specified by:
      createRelative in interface Resource
      Throws:
      IOException

    • getFilename

      public String getFilename()
      Determine a filename for this resource, i.e. typically the last part of the path: for example, "myfile.txt".
      Specified by:
      getFilename in interface Resource
      Specified by:
      getFilename in interface Resource
      Returns:
      null if this type of resource does not have a filename, otherwise the file name.

    • getDescription

      @Nonnull public String getDescription()
      Return a description for this resource, to be used for error output when working with the resource.

      Implementations are also encouraged to return this value from their toString method.

      Specified by:
      getDescription in interface Resource
      Specified by:
      getDescription in interface Resource
      Returns:
      a description for this resource.
      See Also:

    • getLogPrefix

      @Nonnull @NotEmpty protected String getLogPrefix()
      Return a prefix for logging messages for this component.
      Returns:
      a string for insertion at the beginning of any log messages