com.googlecode.sarasvati.load
Interface GraphLoader<G extends Graph>

All Known Implementing Classes:

AbstractGraphLoader, GraphLoaderImpl

public interface GraphLoader<G extends Graph>

Interface for loading process definitions into a GraphRepository. Should not be considered thread-safe.

Author:

Paul Lorenz

Method Summary

boolean	isLoaded(String name) Returns true if the graph has been loaded into the associated GraphRepository, false otherwise.
void	load(File file) Loads the given XML process definition file.
void	loadDefinition(ProcessDefinition procDef) Loads the given process definition.
void	loadDefinition(ProcessDefinition procDef, String customId) Loads the given process definition, giving it the passed in custom identifier.
<T> void	loadDefinition(ProcessDefinitionTranslator<T> translator, T source) Takes a ProcessDefinitionTranslator, applies it to the given source and loads the resulting ProcessDefinition.
<T> void	loadDefinition(ProcessDefinitionTranslator<T> translator, T source, String customId) Takes a ProcessDefinitionTranslator, applies it to the given source and loads the resulting ProcessDefinition.
List<LoadResult>	loadNewAndChanged(File baseDir) Loads all new and changed process definitions under the given base directory.
List<LoadResult>	loadNewAndChanged(File baseDir, FilenameFilter filter) Loads all new and changed process definitions under the given base directory that match the given file name filter.
List<LoadResult>	loadWithDependencies(String name, ProcessDefinitionResolver resolver) Loads the named process definition.

Method Detail

loadDefinition

void loadDefinition(ProcessDefinition procDef)
                    throws SarasvatiLoadException

Loads the given process definition.

Equivalent to loadDefinition( procDef, null )

Throws:

SarasvatiLoadException

See Also:

loadDefinition(ProcessDefinition, String)

loadDefinition

void loadDefinition(ProcessDefinition procDef,
                    String customId)
                    throws SarasvatiLoadException

Loads the given process definition, giving it the passed in custom identifier.

Parameters:

procDef - The process definition to load

customId - The custom identifier to give the loaded process definition

Throws:

SarasvatiLoadException - Thrown if an error occurs during load, or the loader has a validator which throws an exception.

isLoaded

boolean isLoaded(String name)

Returns true if the graph has been loaded into the associated GraphRepository, false otherwise.

Parameters:

name - The name of the graph being searched for

Returns:

true if the graph has been loaded into the associated GraphRepository, false otherwise.

loadNewAndChanged

List<LoadResult> loadNewAndChanged(File baseDir)
                                   throws SarasvatiLoadException

Loads all new and changed process definitions under the given base directory. Uses the default file name filter, which matches all files with the .wf.xml extension.

Equivalent to loadNewAndChanged( baseDir, null );

Throws:

SarasvatiLoadException

See Also:

loadNewAndChanged(File, FilenameFilter)

loadNewAndChanged

List<LoadResult> loadNewAndChanged(File baseDir,
                                   FilenameFilter filter)
                                   throws SarasvatiLoadException

Loads all new and changed process definitions under the given base directory that match the given file name filter.

This method works as follows:

1. It finds and parse all process definitions under the given base directory that match the given filename filter.
2. A SHA-1 hash is calculated for each process definition. This hash is based on the sorted contents of the process definition. Changes in the ordering of the file and changes to whitespace outside of elements containing text will not result in a hash change.
3. The process definitions are sorted by dependency, that for any given process definition, its dependencies will be inspected first.
4. The sorted set of process definitions will be inspected.
   • If a process definition is new, i.e. it does not exist in the GraphRepository, it will be marked for load
   • If a process definition is updated, i.e. the SHA-1 hash does not match the value in Graph.getCustomId() for the new graph of the same name in the repository, it will be marked for load.
   • If a dependency (referenced external) of a process definition is marked for load, the process definition will also be marked for load.

All process definitions marked for load will then be loaded, in dependency order.

Parameters:

baseDir - The directory under which to recursively search for process definitions

filter - The filename filter to use to find process definition files. May be null, in which case the default filter is used. The default filter matches all files with the .wf.xml extension.

Returns:

The list of load results, which indicate which process definitions have been loaded and the reason why they were loaded (new, updated, dependency changed).

Throws:

SarasvatiLoadException - Thrown if an error occurs during the load or if the GraphValidator throws an exception.

loadDefinition

<T> void loadDefinition(ProcessDefinitionTranslator<T> translator,
                        T source)
                    throws SarasvatiLoadException

Takes a ProcessDefinitionTranslator, applies it to the given source and loads the resulting ProcessDefinition.

Equivalent to loadDefinition( translator, source, null )

Throws:

SarasvatiLoadException

See Also:

loadDefinition(ProcessDefinitionTranslator, Object, String)

loadDefinition

<T> void loadDefinition(ProcessDefinitionTranslator<T> translator,
                        T source,
                        String customId)
                    throws SarasvatiLoadException

Takes a ProcessDefinitionTranslator, applies it to the given source and loads the resulting ProcessDefinition.

Type Parameters:

T - The type of input that the process definition translator takes.

Parameters:

translator - Class which takes an input and returns a ProcessDefinition

source - The input for the translator (usually an XML file).

customId - The custom ID to give the graph. Example usage is a SHA-1 hash of the process definition.

Throws:

SarasvatiLoadException - Thrown if an error occurs during the load or if the GraphValidator throws an exception.

loadWithDependencies

List<LoadResult> loadWithDependencies(String name,
                                      ProcessDefinitionResolver resolver)
                                      throws SarasvatiLoadException

Loads the named process definition. The given resolver is used to find the process definition and any of its dependencies that have not yet been loaded. The process definition is only and its dependencies are only loaded if they are new, have changed or dependencies have changed.

Parameters:

name - The name of the process definition to load

resolver - The resolver to use in finding the process definition and its dependencies.

Returns:

The list of load results, which indicate which process definitions have been loaded and the reason why they were loaded (new, updated, dependency changed).

Throws:

SarasvatiLoadException - Thrown if an error occurs during the load or if the GraphValidator throws an exception.

load

void load(File file)
          throws SarasvatiLoadException

Loads the given XML process definition file.

Equivalent to loadDefinition( new XmlLoader(), file );

Parameters:

file - The xml file to load

Throws:

SarasvatiLoadException - Thrown if an error occurs during the load or if the GraphValidator throws an exception.