7.4.7.Examples

To assist you further during your utilization or evaluation of OpenLink's Drivers for JDBC a number of demonstration JDBC compliant Applets and Applications are bundled with your OpenLink Driver for JDBC installation, our demo programs are provided in both binary and source code format for your free use.

Example 1

This sample performs a simple insert and retrieval of data against the Virtuoso database.

  1. Open your command shell and change to the "ex1" directory

  2. The following required files need to be placed in the ./lib directory:

    antlr-2.7.6.jar
    commons-collections-3.1.jar
    commons-logging-1.0.4.jar
    dom4j-1.6.1.jar
    hibernate3.jar
    javassist-3.4.GA.jar
    jta-1.1.jar
    lib.lst
    log4j-1.2.15.jar
    slf4j-api-1.5.10.jar
    slf4j-api-1.5.2.jar
    slf4j-jcl-1.5.10.jar
    virtjdbc4.jar
    virt_dialect.jar
    
  3. Run the example with "ant run" and read the log output on the console:

    $ ant run
    Buildfile: build.xml
    
    clean:
       [delete] Deleting directory /Users/hughwilliams/hibernate/ex1/bin
        [mkdir] Created dir: /Users/hughwilliams/hibernate/ex1/bin
    
    copy-resources:
         [copy] Copying 3 files to /Users/hughwilliams/hibernate/ex1/bin
         [copy] Copied 2 empty directories to 1 empty directory under /Users/hughwilliams/hibernate/ex1/bin
    
    compile:
        [javac] Compiling 3 source files to /Users/hughwilliams/hibernate/ex1/bin
    
    run:
         [java] Hibernate: insert into Event (EVENT_DATE, title) values (?, ?)
         [java] Hibernate: select identity_value()
         [java] Hibernate: insert into Event (EVENT_DATE, title) values (?, ?)
         [java] Hibernate: select identity_value()
         [java] Hibernate: select event0_.EVENT_ID as EVENT1_0_, event0_.EVENT_DATE as EVENT2_0_, event0_.title as title0_ from Event event0_
         [java] Event: My Event1 Time: 2010-03-14 03:27:51.0
         [java] Event: My Event2 Time: 2010-03-14 03:27:53.0
    
    BUILD SUCCESSFUL
    Total time: 3 seconds
    
  4. Hibernate logging levels can be varied by changing the settings in the src/hibernate.cfg.xml and src/log4j.properties files.

Example 2

Hello World with Java Persistence

  1. Open your command shell and change to the "ex2" directory

  2. The following required files need to be placed in the ./lib directory:

    
    antlr-2.7.6.jar
    asm-attrs.jar
    asm.jar
    c3p0-0.9.0.jar
    cglib-2.1.3.jar
    commons-collections-2.1.1.jar
    commons-logging-1.0.4.jar
    dom4j-1.6.1.jar
    ejb3-persistence.jar
    freemarker.jar
    hibernate-annotations.jar
    hibernate-commons-annotations.jar
    hibernate-entitymanager.jar
    hibernate-tools.jar
    hibernate3.jar
    javassist.jar
    jboss-archive-browsing.jar
    jta.jar
    log4j-1.2.13.jar
    virtjdbc4.jar
    virt_dialect.jar
    
  3. Use "ant schemaexport" to export a database schema automatically to the database. Ignore any errors about failing ALTER TABLE statements, they are thrown because there are no tables when you run this for the first time.

    $ ant schemaexport
    Buildfile: build.xml
    
    compile:
    
    copymetafiles:
    
    schemaexport:
    [hibernatetool] Executing Hibernate Tool with a JPA Configuration
    [hibernatetool] 1. task: hbm2ddl (Generates database schema)
    [hibernatetool]
    [hibernatetool]     drop table MESSAGES;
    [hibernatetool]
    [hibernatetool]     create table MESSAGES (
    [hibernatetool]         MESSAGE_ID decimal(20,0)  identity,
    [hibernatetool]         MESSAGE_TEXT varchar(255) null,
    [hibernatetool]         NEXT_MESSAGE_ID decimal(20,0) null,
    [hibernatetool]         primary key (MESSAGE_ID)
    [hibernatetool]     );
    [hibernatetool]
    [hibernatetool]     alter table MESSAGES
    [hibernatetool]         add
    [hibernatetool]         foreign key (NEXT_MESSAGE_ID)
    [hibernatetool]         references MESSAGES;
    
    BUILD SUCCESSFUL
    Total time: 2 seconds
    
  4. Check the DDL that was also exported to the file helloworld-ddl.sql

    $ more helloworld-ddl.sql
    
        drop table MESSAGES;
    
        create table MESSAGES (
            MESSAGE_ID decimal(20,0)  identity,
            MESSAGE_TEXT varchar(255) null,
            NEXT_MESSAGE_ID decimal(20,0) null,
            primary key (MESSAGE_ID)
        );
    
        alter table MESSAGES
            add
            foreign key (NEXT_MESSAGE_ID)
            references MESSAGES;
    
  5. Run the example with "ant run" and read the log output on the console

    $ ant run
    Buildfile: build.xml
    
    compile:
    
    copymetafiles:
    
    run:
         [java] 1 message(s) found:
         [java] Hello World with JPA
    
    BUILD SUCCESSFUL
    Total time: 2 seconds
    
  6. Call ant run again

    $ ant run
    Buildfile: build.xml
    
    compile:
    
    copymetafiles:
    
    run:
         [java] 2 message(s) found:
         [java] Hello World with JPA
         [java] Hello World with JPA
    
    BUILD SUCCESSFUL
    Total time: 2 seconds
    
  7. If you call ant schemaexport again, all tables will be re-created

  8. Hibernate logging levels can be varied by changing the settings in the src/etc/log4j.properties and src/etc/META-INF/persistence.xml files

Example 3

This sample performs more complex insert and retrieval of data against the Virtuoso database.

  1. Open your command shell and change to the "ex3" directory

  2. The following required files need to be placed in the ./lib directory:

    
    

    antlr-2.7.6.jar commons-collections-3.1.jar commons-logging-1.0.4.jar dom4j-1.6.1.jar hibernate3.jar javassist-3.4.GA.jar jta-1.1.jar libs.lst log4j-1.2.15.jar slf4j-api-1.5.10.jar slf4j-api-1.5.2.jar slf4j-jcl-1.5.10.jar virtjdbc4.jar virt_dialect.jar

  3. Run the example with "ant run" and read the log output on the console:

    $ ant run
    Buildfile: build.xml
    
    clean:
       [delete] Deleting directory /Users/hughwilliams/hibernate/ex3/bin
        [mkdir] Created dir: /Users/hughwilliams/hibernate/ex3/bin
    
    copy-resources:
         [copy] Copying 4 files to /Users/hughwilliams/hibernate/ex3/bin
         [copy] Copied 2 empty directories to 1 empty directory under /Users/hughwilliams/hibernate/ex3/bin
    
    compile:
        [javac] Compiling 4 source files to /Users/hughwilliams/hibernate/ex3/bin
        [javac] Note: Some input files use unchecked or unsafe operations.
        [javac] Note: Recompile with -Xlint:unchecked for details.
    
    run:
         [java] Hibernate: insert into EVENTS (EVENT_DATE, title) values (?, ?)
         [java] Hibernate: select identity_value()
         [java] Hibernate: insert into EVENTS (EVENT_DATE, title) values (?, ?)
         [java] Hibernate: select identity_value()
         [java] Hibernate: insert into PERSON (age, firstname, lastname) values (?, ?, ?)
         [java] Hibernate: select identity_value()
         [java] Hibernate: select person0_.PERSON_ID as PERSON1_2_0_, event2_.EVENT_ID as EVENT1_0_1_, person0_.age as age2_0_, person0_.firstname as firstname2_0_, person0_.lastname as lastname2_0_, event2_.EVENT_DATE as EVENT2_0_1_, event2_.title as title0_1_, events1_.PERSON_ID as PERSON2_0__, events1_.EVENT_ID as EVENT1_0__ from PERSON person0_ left outer join PERSON_EVENT events1_ on person0_.PERSON_ID=events1_.PERSON_ID left outer join EVENTS event2_ on events1_.EVENT_ID=event2_.EVENT_ID where person0_.PERSON_ID=?
         [java] Hibernate: select event0_.EVENT_ID as EVENT1_0_0_, event0_.EVENT_DATE as EVENT2_0_0_, event0_.title as title0_0_ from EVENTS event0_ where event0_.EVENT_ID=?
         [java] Hibernate: select participan0_.EVENT_ID as EVENT1_1_, participan0_.PERSON_ID as PERSON2_1_, person1_.PERSON_ID as PERSON1_2_0_, person1_.age as age2_0_, person1_.firstname as firstname2_0_, person1_.lastname as lastname2_0_ from PERSON_EVENT participan0_ left outer join PERSON person1_ on participan0_.PERSON_ID=person1_.PERSON_ID where participan0_.EVENT_ID=?
         [java] Hibernate: insert into PERSON_EVENT (PERSON_ID, EVENT_ID) values (?, ?)
         [java] Hibernate: update PERSON set age=?, firstname=?, lastname=? where PERSON_ID=?
         [java] Added person 1 to event 2
         [java] Hibernate: insert into PERSON (age, firstname, lastname) values (?, ?, ?)
         [java] Hibernate: select identity_value()
         [java] Hibernate: select person0_.PERSON_ID as PERSON1_2_0_, person0_.age as age2_0_, person0_.firstname as firstname2_0_, person0_.lastname as lastname2_0_ from PERSON person0_ where person0_.PERSON_ID=?
         [java] Hibernate: select emailaddre0_.PERSON_ID as PERSON1_0_, emailaddre0_.EMAIL_ADDR as EMAIL2_0_ from PERSON_EMAIL_ADDR emailaddre0_ where emailaddre0_.PERSON_ID=?
         [java] Hibernate: insert into PERSON_EMAIL_ADDR (PERSON_ID, EMAIL_ADDR) values (?, ?)
         [java] Hibernate: select person0_.PERSON_ID as PERSON1_2_0_, person0_.age as age2_0_, person0_.firstname as firstname2_0_, person0_.lastname as lastname2_0_ from PERSON person0_ where person0_.PERSON_ID=?
         [java] Hibernate: select emailaddre0_.PERSON_ID as PERSON1_0_, emailaddre0_.EMAIL_ADDR as EMAIL2_0_ from PERSON_EMAIL_ADDR emailaddre0_ where emailaddre0_.PERSON_ID=?
         [java] Hibernate: insert into PERSON_EMAIL_ADDR (PERSON_ID, EMAIL_ADDR) values (?, ?)
         [java] Added two email addresses (value typed objects) to person entity : 1
         [java] Hibernate: select event0_.EVENT_ID as EVENT1_0_, event0_.EVENT_DATE as EVENT2_0_, event0_.title as title0_ from EVENTS event0_
         [java] Event: My Event Time: 2010-03-14 03:30:02.0
         [java] Event: My Event Time: 2010-03-14 03:30:06.0
    
    BUILD SUCCESSFUL
    Total time: 5 seconds
    
  4. Hibernate logging levels can be varied by changing the settings in the src/hibernate.cfg.xml and src/log4j.properties files.

Example 4

This example demonstrates how to make Multi Thread Virtuoso connection using JDBC.

It starts 3 threads: one thread executes SPARQL select and two threads execute SPARQL inserts:

import java.util.*;
import java.sql.*;
import java.math.*;

public class MTtest extends Thread {

  int mode = 0;
  int startId = 0;

  static  String urlDB = "jdbc:virtuoso://localhost:1111";

 public MTtest(int _mode, int _init) {
   mode = _mode;
   startId = _init;
 }

 void prnRs(ResultSet rs)
 {
   try {
     ResultSetMetaData rsmd;

     System.out.println(">>>>>>>>");
     rsmd = rs.getMetaData();
     int cnt = rsmd.getColumnCount();

       while(rs.next()) {
         Object o;

         System.out.print("Thread:"+Thread.currentThread().getId()+"  ");
         for (int i = 1; i <= cnt; i++) {
           o = rs.getObject(i);
           if (rs.wasNull())
             System.out.print("<NULL> ");
           else
             System.out.print("["+ o + "] ");
         }
         System.out.println();
       }

   } catch (Exception e) {
     System.out.println(e);
     e.printStackTrace();
   }
   System.out.println(">>>>>>>>");
 }

 public static void main(String argv[])
 {
  try {

    Class.forName("virtuoso.jdbc3.Driver");

    Connection conn = DriverManager.getConnection(urlDB,"dba","dba");
    Statement st = conn.createStatement();

    st.execute("sparql clear graph <mttest>");
    st.execute("sparql insert into graph <mttest> { <xxx> <P01> \"test1\" }");
    st.execute("sparql insert into graph <mttest> { <xxx> <P01> \"test2\" }");
    st.execute("sparql insert into graph <mttest> { <xxx> <P01> \"test3\" }");
    st.execute("sparql insert into graph <mttest> { <xxx> <P01> \"test4\" }");
    st.execute("sparql insert into graph <mttest> { <xxx> <P01> \"test5\" }");
    conn.close();

    int init = 0;

    for(int i=0; i < 2; i++) {
      MTtest thr1 = new MTtest(1, init);
      init+=10;

      MTtest thr2 = new MTtest(0, init);
      init+=10;

      MTtest thr3 = new MTtest(0, init);
      init+=10;

      thr1.start();
      thr2.start();
      thr3.start();

      thr1.join();
      thr2.join();
      thr3.join();
    }

    System.out.println("===End===");

  } catch (Exception e) {
    System.out.print(e);
    e.printStackTrace();
  }
 }

 public void run( )
 {
  try {

    Connection conn = DriverManager.getConnection(urlDB,"dba","dba");
    Statement st;

    st = conn.createStatement();

    if (mode == 1)
    {
      String query = "sparql SELECT * from <mttest> WHERE {?s ?p ?o}";
      ResultSet rs = st.executeQuery(query);
      prnRs(rs);
    }
    else
    {
      long id = Thread.currentThread().getId();
      for (int i =0; i < 5; i++)
        st.execute("sparql insert into graph <mttest> { <xxx"+startId+"> <P"+id+"> \"test"+i+"\" }");

      System.out.println("\nThread:"+Thread.currentThread().getId()+"  ===Rows Inserted===");
    }

    conn.close();

  } catch (SQLException e) {
        System.out.println("===========================================================");
        System.out.println(">>["+e.getMessage()+"]");
        System.out.println(">>["+e.getErrorCode()+"]");
        System.out.println(">>["+e.getSQLState()+"]");
        System.out.println(e);
        System.out.println("===========================================================");
        e.printStackTrace();
        System.exit(-1);
  } catch (Exception e) {
        System.out.println("===========================================================");
        System.out.println(e);
        System.out.println("===========================================================");
        e.printStackTrace();
        System.exit(-1);
  }
 } // run( )

}