-- 作者：lngxt
-- 发布时间：4/15/2005 9:34:00 PM
-- 用jena存储两个.owl时出现的问题
这是Jena Document中的例子，在mysql中存储两个.owl。
出现的问题是
Exception in thread "main" com.hp.hpl.jena.db.RDFRDBException: Failure to instantiate DB Driver:MySQL java.sql.SQLException: No suitable driver
上面要求的是这个驱动mysql-connector-java-3.0.8-stable.jar ，可我下载到的驱动是mysql-connector-java-3.0.8-stable.zip，这里面有个mysql-connector-java-3.0.8-stable-bin.jar，难道这个驱动不能用？
可我另写了一个小程序是可以连上去的，不知道是怎么回事，
有没有人试过这个例子？ import java.util.*;
import com.hp.hpl.jena.db.*;
import com.hp.hpl.jena.ontology.*;
import com.hp.hpl.jena.rdf.model.*; public class PersistentOntology {
// Constants
public static final String ONT1 = "urn:x-hp-jena:test1";
public static final String ONT2 = "urn:x-hp-jena:test2";
static String DB_URL = "jdbc:mysql://localhost/jenatest";
static String DB_USER = "root";
static String DB_PASSWD = "chair";
static String DB = "MySQL";
static String DBDRIVER_CLASS = "com.mysql.jdbc.Driver"; public static void main( String[] args ) {
new PersistentOntology().go( args );
} protected void go( String[] args ) {
if (args.length > 0 && args[0].equals( "reload" )) {
reloadDB();
}
listClasses();
} protected void reloadDB() {
ModelMaker maker = getMaker(); // clear out the old
if (maker.hasModel( ONT1 )) maker.removeModel( ONT1 );
if (maker.hasModel( ONT2 )) maker.removeModel( ONT2 ); // create a spec for the new ont model
OntModelSpec spec = new OntModelSpec( OntModelSpec.OWL_MEM_RULE_INF );
spec.setModelMaker( maker ); // create the base model as a persistent model
Model base = maker.createModel( ONT1 );
OntModel m = ModelFactory.createOntologyModel( spec, base ); // tell m where to find the content for ont2
m.getDocumentManager().addAltEntry( ONT2, "file:test2.owl" ); // now load the document for test1, which will import ONT2
m.read( "file:test.owl" );
} protected void listClasses() {
OntModelSpec spec = new OntModelSpec( OntModelSpec.OWL_MEM_RULE_INF );
spec.setModelMaker( getMaker() ); OntModel m = ModelFactory.createOntologyModel( spec, getMaker().createModel( ONT1 ) ); for (Iterator i = m.listClasses(); i.hasNext(); ) {
OntClass c = (OntClass) i.next();
System.out.println( "Class " + c.getURI() );
}
} protected ModelMaker getMaker() {
try {
IDBConnection conn = new DBConnection ( DB_URL, DB_USER, DB_PASSWD,DB);
// Create a model maker object
return ModelFactory.createModelRDBMaker(conn); }
catch (Exception e) {
e.printStackTrace();
System.exit( 1 );
} return null;
} // Internal implementation methods
}
/********************* test.owl *************************/
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE owl [
<!ENTITY rdf 'http://www.w3.org/1999/02/22-rdf-syntax-ns#'>
<!ENTITY rdfs 'http://www.w3.org/2000/01/rdf-schema#'>
<!ENTITY owl 'http://www.w3.org/2002/07/owl#' >
<!ENTITY xsd 'http://www.w3.org/2001/XMLSchema#' >
]> <rdf:RDF
xmlns:owl="&owl;"
xmlns:rdf="&rdf;"
xmlns:rdfs="&rdfs;"
xmlns="urn:x-hp-jena:test1#"
xml:base = "urn:x-hp-jena:test1"
>
<owl:Ontology rdf:about="">
<owl:imports rdf:resource="urn:x-hp-jena:test2" />
</owl:Ontology>
<owl:Class rdf:ID="Test1A"/>
<owl:Class rdf:ID="Test1B">
<rdfs:subClassOf rdf:resource="#Test1A"/>
</owl:Class>
</rdf:RDF> /***************** test2.owl ********************************/
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE owl [
<!ENTITY rdf 'http://www.w3.org/1999/02/22-rdf-syntax-ns#'>
<!ENTITY rdfs 'http://www.w3.org/2000/01/rdf-schema#'>
<!ENTITY owl 'http://www.w3.org/2002/07/owl#' >
<!ENTITY xsd 'http://www.w3.org/2001/XMLSchema#' >
]>
<rdf:RDF
xmlns:owl="&owl;"
xmlns:rdf="&rdf;"
xmlns:rdfs="&rdfs;"
xmlns:test1="urn:x-hp-jena:test1#"
xmlns="urn:x-hp-jena:test2#"
xml:base = "urn:x-hp-jena:test2"
>
<owl:Ontology rdf:about="">
</owl:Ontology>
<owl:Class rdf:ID="Test2A"/>
<test1:Test1A rdf:ID="test1a" />
</rdf:RDF>
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