この例では、Oracle Databaseの接続プーリングを使用します。
import com.hp.hpl.jena.graph.*; import com.hp.hpl.jena.query.*; import oracle.rdf.kv.client.jena.*; public class Example15 { public static void main(String[] args) throws Exception { String szStoreName = args[0]; String szHostName = args[1]; String szHostPort = args[2]; String szModelName = args[3]; int iPoolSize = Integer.parseInt(args[4]); // Property of the pool: wait if no connection is available // at request. boolean bWaitIfBusy = true; System.out.println("Creating OracleNoSQL pool"); OracleNoSqlPool pool = OracleNoSqlPool.createInstance(szStoreName, szHostName, szHostPort, iPoolSize, bWaitIfBusy, true); //lazyInit System.out.println("Done creating OracleNoSql pool"); // grab an Oracle NoSQL connection and do something System.out.println("Get a connection from the pool"); OracleNoSqlConnection conn = pool.getResource(); OracleModelNoSql model = OracleModelNoSql.createOracleModelNoSql(szModelName, conn); System.out.println("Clear model"); model.removeAll(); model.getGraph().add(Triple.create(Node.createURI("u:John"), Node.createURI("u:cousinOf"), Node.createURI("u:Jackie"))); model.close(); //return connection back to the pool conn.dispose(); // grab another Oracle NoSQL connection and do something System.out.println("Get a connection from the pool"); conn = pool.getResource(); model = OracleModelNoSql.createOracleModelNoSql(szModelName, conn); String queryString = "select ?x ?y ?z WHERE {?x ?y ?z}"; System.out.println("Execute query " + queryString); Query query = QueryFactory.create(queryString) ; QueryExecution qexec = QueryExecutionFactory.create(query, model); try { ResultSet results = qexec.execSelect(); ResultSetFormatter.out(System.out, results, query); } finally { qexec.close(); } model.close(); //return connection back to the pool conn.dispose(); // Close pool. // This will close all resources even if they have not been freed up System.out.println("Close pool, this will close all resources"); pool.close(); } }
この例をコンパイルして実行するコマンドと、想定されるJavaコマンドの出力は次のとおりです。
javac -classpath ./:./jena-core-2.7.4.jar:./jena-arq-2.9.4.jar: \ ./sdordfnosqlclient.jar:./kvclient.jar:./xercesImpl-2.10.0.jar: \ ./slf4j-api-1.6.4.jar:./slf4j-log4j12-1.6.4.jar:./log4j/1.2.16.jar: \ ./jena-iri-0.9.4.jar:./xml-apis-1.4.01.jar Example15.java javac -classpath ./:./jena-core-2.7.4.jar:./jena-arq-2.9.4.jar: \ ./sdordfnosqlclient.jar:./kvclient.jar:./xercesImpl-2.10.0.jar: \ ./slf4j-api-1.6.4.jar:./slf4j-log4j12-1.6.4.jar:./log4j/1.2.16.jar: \ ./jena-iri-0.9.4.jar:./xml-apis-1.4.01.jar Example15 <store_name> \ <host_name> <host_port> <graph_name> Creating OracleNoSQL pool Done creating OracleNoSql pool Get a connection from the pool Clear model Get a connection from the pool Execute query select ?x ?y ?z WHERE {?x ?y ?z} ---------------------------------------- | x | y | z | ======================================== | <u:John> | <u:cousinOf> | <u:Jackie> | ---------------------------------------- Close pool, this will close all resources