prajna.structure.accessor

Class RecordAccessorClient

java.lang.Object

prajna.structure.AbstractDataAccessor<DataRecord,DataRecord>

prajna.structure.accessor.RecordAccessor

prajna.structure.accessor.RecordAccessorClient

All Implemented Interfaces:

DataAccessor<DataRecord,DataRecord>

public class RecordAccessorClient
extends RecordAccessor

Class which interacts with server-side SemanticAccessors. The SemanticAccessorClient connects to a RecordAccessorServlet, and retrieves the various data through servlet invocations. The data received from the servlet is transmitted as serialized objects to enhance performance. The data received must be generated from a SemanticAccessor on the server side.

Author:

Edward Swing

Constructor Summary

Constructors

Constructor and Description
RecordAccessorClient() Creates a new SemanticAccessorClient object.
RecordAccessorClient(java.net.URL documentBase) Creates a new DataAccessorClient object.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	extendGraph(java.lang.String graphName, Graph<DataRecord,DataRecord> graph, DataRecord node) Extend the given graph around the specified node.
boolean	extendTree(java.lang.String treeName, Tree<DataRecord> tree, DataRecord node) Extend the given tree around the specified node.
java.util.Set<DataRecord>	getDataset(java.lang.String datasetName) Retrieve the dataset from the underlying data source.
Graph<DataRecord,DataRecord>	getGraph(java.lang.String graphName) Retrieve the graph from the underlying data source.
Grid<DataRecord>	getGrid(java.lang.String gridName) Retrieve the grid from the underlying data source.
Tree<DataRecord>	getTree(java.lang.String treeName) Retrieve the tree from the underlying data source.
protected java.util.Set<DataRecord>	retrieveRecords(DataTemplate template) Stub implementation of retrieveRecords.
void	setDocBase(java.lang.String docBaseStr) Set the document base for this SemanticAccessorClient.
void	setDocBase(java.net.URL documentBase) Set the document base for this SemanticAccessorClient.
void	setInitParameters(java.util.Map<java.lang.String,java.lang.String> parameters) Set any initialization parameters required by the SemanticAccessorClient.
void	setQuery(java.lang.String queryString) Set the query string used to retrieve records.

Methods inherited from class prajna.structure.accessor.RecordAccessor

addFieldHandler, addToGraph, addToTree, createReferenceNode, getFieldHandler, getMaxRecords, getReasoner, getStructureReasoners, setMaxRecords, setReasoner, setReasoner

Methods inherited from class prajna.structure.AbstractDataAccessor

addStructure, addTemplate, getDatasetNames, getGraphNames, getGridNames, getSpec, getStructureType, getTemplate, getTemplateNames, getTreeNames, setConfig, setConfigFile, setConfigFile

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

RecordAccessorClient

public RecordAccessorClient()

Creates a new SemanticAccessorClient object. This no-arg constructor must be initialized with a configuration file or via the setDocBase method before accessing data

RecordAccessorClient

public RecordAccessorClient(java.net.URL documentBase)

Creates a new DataAccessorClient object. This constructor needs a document base so that it will know where to communicate with the server.

Parameters:

documentBase - The document base

Method Detail

extendGraph

public boolean extendGraph(java.lang.String graphName,
                  Graph<DataRecord,DataRecord> graph,
                  DataRecord node)

Extend the given graph around the specified node. This method uses the basic graph retrieval, but adds the node's name as an additional argument attached to the graph name

Specified by:

extendGraph in interface DataAccessor<DataRecord,DataRecord>

Overrides:

extendGraph in class RecordAccessor

Parameters:

graphName - The name of the graph

graph - The graph to extend

node - The node to use as an extension point.

Returns:

true if more data was added to the graph, false otherwise.

extendTree

public boolean extendTree(java.lang.String treeName,
                 Tree<DataRecord> tree,
                 DataRecord node)

Extend the given tree around the specified node. This method adds any children which are not already part of the tree. This method uses the basic tree retrieval, but adds the node's name as an additional argument attached to the tree name

Specified by:

extendTree in interface DataAccessor<DataRecord,DataRecord>

Overrides:

extendTree in class RecordAccessor

Parameters:

treeName - The name of the graph

tree - The graph to extend

node - The node to use as an extension point.

Returns:

true if more data was added to the tree, false otherwise.

getDataset

public java.util.Set<DataRecord> getDataset(java.lang.String datasetName)

Retrieve the dataset from the underlying data source. This method queries the servlet to retrieve the named dataset. The dataset is retrieved from the servlet in a serialized form.

Specified by:

getDataset in interface DataAccessor<DataRecord,DataRecord>

Overrides:

getDataset in class RecordAccessor

Parameters:

datasetName - the name of the dataset

Returns:

the dataset

getGraph

public Graph<DataRecord,DataRecord> getGraph(java.lang.String graphName)

Retrieve the graph from the underlying data source. This method queries the servlet to retrieve the named graph. The graph is retrieved from the servlet in a serialized form.

Specified by:

getGraph in interface DataAccessor<DataRecord,DataRecord>

Overrides:

getGraph in class RecordAccessor

Parameters:

graphName - the name of the graph

Returns:

the graph

getGrid

public Grid<DataRecord> getGrid(java.lang.String gridName)

Retrieve the grid from the underlying data source. This method queries the servlet to retrieve the named grid. The grid is retrieved from the servlet in a serialized form.

Specified by:

getGrid in interface DataAccessor<DataRecord,DataRecord>

Overrides:

getGrid in class RecordAccessor

Parameters:

gridName - the name of the grid

Returns:

the grid

getTree

public Tree<DataRecord> getTree(java.lang.String treeName)

Retrieve the tree from the underlying data source. This method queries the servlet to retrieve the named tree. The tree is retrieved from the servlet in a serialized form.

Specified by:

getTree in interface DataAccessor<DataRecord,DataRecord>

Overrides:

getTree in class RecordAccessor

Parameters:

treeName - the name of the tree

Returns:

the tree

retrieveRecords

protected java.util.Set<DataRecord> retrieveRecords(DataTemplate template)

Stub implementation of retrieveRecords. Since this SemanticAccessor retrieves its data via a web call, this method is never used.

Specified by:

retrieveRecords in class RecordAccessor

Parameters:

template - the DataTemplate

Returns:

an empty set

setDocBase

public void setDocBase(java.lang.String docBaseStr)

Set the document base for this SemanticAccessorClient.

Parameters:

docBaseStr - The document base

setDocBase

public void setDocBase(java.net.URL documentBase)

Set the document base for this SemanticAccessorClient. This method queries the servlet without arguments. The response from the servlet should return configuration information

Parameters:

documentBase - The document base

setInitParameters

public void setInitParameters(java.util.Map<java.lang.String,java.lang.String> parameters)

Set any initialization parameters required by the SemanticAccessorClient. This class requires a docBase to be defined, either from the constructor, config file, or with the mutator. The docBase should be the servlet that this accessor will consume.

Parameters:

parameters - a map of initialization parameters

setQuery

public void setQuery(java.lang.String queryString)

Set the query string used to retrieve records. This method should transform the query string into a format which the accessor can parse. The query string supports a query of the form field=value. The query string is appended to all servlet requests.

Specified by:

setQuery in class AbstractDataAccessor<DataRecord,DataRecord>

Parameters:

queryString - the query string