Class PropertyCacheFile

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Field Details

• CONFIG_HASH_KEY

  public static final String CONFIG_HASH_KEY

  The property key to use for storing the hashcode of the configuration. To avoid name clashes with the files that are checked the key is chosen in such a way that it cannot be a valid file name.

  See Also:

  • Constant Field Values

• EXTERNAL_RESOURCE_KEY_PREFIX

  public static final String EXTERNAL_RESOURCE_KEY_PREFIX

  The property prefix to use for storing the hashcode of an external resource. To avoid name clashes with the files that are checked the prefix is chosen in such a way that it cannot be a valid file name and makes it clear it is a resource.

  See Also:

  • Constant Field Values

• BUFFER_SIZE

  private static final int BUFFER_SIZE

  Size of default byte array for buffer.

  See Also:

  • Constant Field Values

• BUFFER

  private static final byte[] BUFFER

  Default buffer for reading from streams.

• BASE_16

  private static final int BASE_16

  Default number for base 16 encoding.

  See Also:

  • Constant Field Values

• details

  private final Properties details

  The details on files.

• config

  private final Configuration config

  Configuration object.

• fileName

  private final String fileName

  File name of cache.

• configHash

  private String configHash

  Generated configuration hash.

Constructor Details

• PropertyCacheFile

  public PropertyCacheFile (Configuration config, String fileName)

  Creates a new PropertyCacheFile instance.

  Parameters:

  config - the current configuration, not null

  fileName - the cache file

  Throws:

  IllegalArgumentException - when either arguments are null

Method Details

• load

  public void load () throws IOException

  Load cached values from file.

  Throws:

  IOException - when there is a problems with file read

• persist

  public void persist () throws IOException

  Cleans up the object and updates the cache file.

  Throws:

  IOException - when there is a problems with file save

• reset

  public void reset ()

  Resets the cache to be empty except for the configuration hash.

• isInCache

  public boolean isInCache (String uncheckedFileName, long timestamp)

  Checks that file is in cache.

  Parameters:

  uncheckedFileName - the file to check

  timestamp - the timestamp of the file to check

  Returns:

  whether the specified file has already been checked ok

• put

  public void put (String checkedFileName, long timestamp)

  Records that a file checked ok.

  Parameters:

  checkedFileName - name of the file that checked ok

  timestamp - the timestamp of the file

• get

  public String get (String name)

  Retrieves the hash of a specific file.

  Parameters:

  name - The name of the file to retrieve.

  Returns:

  The has of the file or null.

• remove

  public void remove (String checkedFileName)

  Removed a specific file from the cache.

  Parameters:

  checkedFileName - The name of the file to remove.

• getHashCodeBasedOnObjectContent

  private static String getHashCodeBasedOnObjectContent (Serializable object)

  Calculates the hashcode for the serializable object based on its content.

  Parameters:

  object - serializable object.

  Returns:

  the hashcode for serializable object.

  Throws:

  IllegalStateException - when some unexpected happened.

• serialize

  private static void serialize (Serializable object, OutputStream outputStream) throws IOException

  Serializes object to output stream.

  Parameters:

  object - object to be serialized

  outputStream - serialization stream

  Throws:

  IOException - if an error occurs

• putExternalResources

  public void putExternalResources (Set<String> locations)

  Puts external resources in cache. If at least one external resource changed, clears the cache.

  Parameters:

  locations - locations of external resources.

• loadExternalResources

  private static Set<PropertyCacheFile.ExternalResource> loadExternalResources (Set<String> resourceLocations)

  Loads a set of PropertyCacheFile.ExternalResource based on their locations.

  Parameters:

  resourceLocations - locations of external configuration resources.

  Returns:

  a set of PropertyCacheFile.ExternalResource.

• loadExternalResource

  private static byte[] loadExternalResource (String location) throws IOException, CheckstyleException

  Loads the content of external resource.

  Parameters:

  location - external resource location.

  Returns:

  array of bytes which represents the content of external resource in binary form.

  Throws:

  IOException - if error while loading occurs.

  CheckstyleException - if error while loading occurs.

• toByteArray

  private static byte[] toByteArray (InputStream stream) throws IOException

  Reads all the contents of an input stream and returns it as a byte array.

  Parameters:

  stream - The input stream to read from.

  Returns:

  The resulting byte array of the stream.

  Throws:

  IOException - if there is an error reading the input stream.

• areExternalResourcesChanged

  private boolean areExternalResourcesChanged (Set<PropertyCacheFile.ExternalResource> resources)

  Checks whether the contents of external configuration resources were changed.

  Parameters:

  resources - a set of PropertyCacheFile.ExternalResource.

  Returns:

  true if the contents of external configuration resources were changed.

• isResourceChanged

  private boolean isResourceChanged (PropertyCacheFile.ExternalResource resource)

  Checks whether the resource is changed.

  Parameters:

  resource - resource to check.

  Returns:

  true if resource is changed.

• fillCacheWithExternalResources

  private void fillCacheWithExternalResources (Set<PropertyCacheFile.ExternalResource> externalResources)

  Fills cache with a set of PropertyCacheFile.ExternalResource. If external resource from the set is already in cache, it will be skipped.

  Parameters:

  externalResources - a set of PropertyCacheFile.ExternalResource.

• isResourceLocationInCache

  private boolean isResourceLocationInCache (String location)

  Checks whether resource location is in cache.

  Parameters:

  location - resource location.

  Returns:

  true if resource location is in cache.