com.bigdata.samples
Class SampleCode

java.lang.Object
  com.bigdata.samples.SampleCode

Direct Known Subclasses:

LoadNamedGraphs, TestNamedGraphs

public class SampleCode
extends Object

Demonstrate how to use bigdata. You are free to use this code for whatever purpose without restriction.

Author:

mikep

Field Summary

protected static org.apache.log4j.Logger

log Do you have log4j set up correctly? Bigdata turns its logging level way down by default (WARN).

Constructor Summary

SampleCode()

Method Summary

protected void	compare(TupleQueryResult result, Collection<BindingSet> answer)
protected BindingSet	createBindingSet(Binding... bindings)
void	doLUBMTest(String lubmResource) Run a simple LUBM load and query benchmark.
void	doU1()
void	doU10()
void	executeConstructQuery(Repository repo, String query, QueryLanguage ql) Execute a "construct" query.
boolean	executeFreeTextQuery(Repository repo) Demonstrate execution of a free-text query.
void	executeHistoricalQuery(Repository repo) Demonstrate execution of historical query using a read-only transaction.
boolean	executeProvenanceQuery(Repository repo) Demonstrate execution of statement level provenance.
void	executeSelectQuery(Repository repo, String query, QueryLanguage ql) Execute a "select" query.
Reader	getReader(Class c, String resource)
Properties	loadProperties(String resource) Load a Properties object from a file.
void	loadSomeData(Repository repo) Add a statement to a repository.
void	loadSomeDataFromADocument(Repository repo, String resource, String baseURL) Load a document into a repository.
static void	main(String[] args) Are you running with the -server JVM option? You should be.
void	readSomeData(Repository repo, URI uri) Read some statements from a repository.

Methods inherited from class java.lang.Object

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

Field Detail

log

protected static final org.apache.log4j.Logger log

Do you have log4j set up correctly? Bigdata turns its logging level way down by default (WARN). You should not be seeing INFO or DEBUG log statements from bigdata - if you are, then this will severely impact performance.

Constructor Detail

SampleCode

public SampleCode()

Method Detail

loadProperties

public Properties loadProperties(String resource)
                          throws Exception

Load a Properties object from a file.

Parameters:

resource -

Returns:

Throws:

Exception

loadSomeData

public void loadSomeData(Repository repo)
                  throws Exception

Add a statement to a repository.

Parameters:

repo -

Throws:

Exception

loadSomeDataFromADocument

public void loadSomeDataFromADocument(Repository repo,
                                      String resource,
                                      String baseURL)
                               throws Exception

Load a document into a repository.

Parameters:

repo -

resource -

baseURL -

Throws:

Exception

readSomeData

public void readSomeData(Repository repo,
                         URI uri)
                  throws Exception

Read some statements from a repository.

Parameters:

repo -

uri -

Throws:

Exception

executeSelectQuery

public void executeSelectQuery(Repository repo,
                               String query,
                               QueryLanguage ql)
                        throws Exception

Execute a "select" query.

Parameters:

repo -

query -

ql -

Throws:

Exception

executeConstructQuery

public void executeConstructQuery(Repository repo,
                                  String query,
                                  QueryLanguage ql)
                           throws Exception

Execute a "construct" query.

Parameters:

repo -

query -

ql -

Throws:

Exception

executeFreeTextQuery

public boolean executeFreeTextQuery(Repository repo)
                             throws Exception

Demonstrate execution of a free-text query.

Parameters:

repo -

Throws:

Exception

executeProvenanceQuery

public boolean executeProvenanceQuery(Repository repo)
                               throws Exception

Demonstrate execution of statement level provenance.

Parameters:

repo -

Throws:

Exception

executeHistoricalQuery

public void executeHistoricalQuery(Repository repo)
                            throws Exception

Demonstrate execution of historical query using a read-only transaction.

Note: Bigdata preserves historical commit points until their release age expires. This behavior is controlled by the deployment mode (RW, WORM, or cluster) and by AbstractTransactionService.Options#MIN_RELEASE_AGE. Except for the WORM deployment mode, you MUST guard a historical commit point on which you want to read using a read-lock. The read-lock itself is just a read-only connection. It can be obtained for any historical commit point that you want to "pin" and can be released once you are no longer need to "pin" that commit point.

The read-lock is not required for the WORM deployment because it never releases historical commit points.

Parameters:

repo -

Throws:

Exception

doLUBMTest

public void doLUBMTest(String lubmResource)
                throws Exception

Run a simple LUBM load and query benchmark.

Parameters:

lubmResource - the ZIP file containing the LUBM data files

filter - helps filter out non-data files in the ZIP file

Throws:

Exception

doU10

public void doU10()
           throws Exception

Throws:

Exception

doU1

public void doU1()
          throws Exception

Throws:

Exception

getReader

public Reader getReader(Class c,
                        String resource)

main

public static void main(String[] args)

Are you running with the -server JVM option? You should be. Also, try increasing heap size with -Xmx512m or even -Xmx1024m if you have enough RAM.

Parameters:

args -

createBindingSet

protected BindingSet createBindingSet(Binding... bindings)

compare

protected void compare(TupleQueryResult result,
                       Collection<BindingSet> answer)
                throws QueryEvaluationException

Throws:

QueryEvaluationException