In preparation for some Java work I wanted to configure and test the Drizzle JDBC Driver. Any chance to swing Drizzle into a MySQL discussion is worth the research. What I found was an issue compiling and an issue running on Ubuntu 9.04

You can start by downloading and building the Drizzle JDBC. My first problem was when I tried to build a usable .jar. I got errors in the test cases which caused by default no built .jar to work with. I raised Bug #432146 – org.drizzle.jdbc.MySQLDriverTest Tests fail. As I stated it may not be a real bug, but it seems at present that you require a running MySQL instance as well as a running Drizzle instance. In my case I didn’t have MySQL running, and I think to be fair, I should be able to build a Drizzle driver without MySQL.

Anyway, as per the Wiki Docs I proceeded to package without successful test cases. My next problem was more interesting, and perhaps found earlier from the tests?

I first created a test schema my code was going to use.

$ ~/drizzle/deploy/bin/drizzle
Your Drizzle connection id is 724
Server version: 2009.09.1126 Source distribution (trunk)

drizzle> create schema test_java;
Query OK, 1 row affected (0 sec)
drizzle> exit

I wrote a simple Java program.

$ cat ExampleDrizzle.java
import java.sql.*;

public class ExampleDrizzle {

  public static void main(String args[]) {

    try {
      Class.forName("org.drizzle.jdbc.Driver");
    } catch (Exception e) {
      System.out.println(e.getMessage());
      System.exit(1);
    }

    try {
      Connection con = DriverManager.getConnection("jdbc:drizzle://localhost:4427/test_java");
      Statement st = con.createStatement();
      st.executeUpdate("CREATE TABLE a (id int not null primary key, value varchar(20))");
      st.close();
      con.close();
    } catch (SQLException e) {
      System.out.println(e.getMessage());
    }
  }
}

Compiled.

$ javac ExampleDrizzle.java

Ran.

$ java ExampleDrizzle
org.drizzle.jdbc.Driver not found in gnu.gcj.runtime.SystemClassLoader{urls=[file:mysql-connector-java-5.1.8-bin.jar,file:./], parent=gnu.gcj.runtime.ExtensionClassLoader{urls=[], parent=null}}

Oops, been a while since using Java. I was amazed I could write the code in vi in the first place.

$ export CLASSPATH=drizzle-jdbc-0.5-SNAPSHOT.jar:.
$ java ExampleDrizzle
17-Sep-09 6:48:45 PM org.drizzle.jdbc.internal.drizzle.DrizzleProtocol 
INFO: Connected to: localhost:4427
Exception in thread "main" java.lang.NoClassDefFoundError: org.drizzle.jdbc.DrizzleConnection
   at java.lang.Class.initializeClass(libgcj.so.90)
   at org.drizzle.jdbc.Driver.connect(Driver.java:74)
   at java.sql.DriverManager.getConnection(libgcj.so.90)
   at ExampleDrizzle.main(ExampleDrizzle.java:15)
Caused by: java.lang.ClassNotFoundException: java.sql.SQLFeatureNotSupportedException not found in gnu.gcj.runtime.SystemClassLoader{urls=[file:drizzle-jdbc-0.5-SNAPSHOT.jar,file:./], parent=gnu.gcj.runtime.ExtensionClassLoader{urls=[], parent=null}}
   at java.net.URLClassLoader.findClass(libgcj.so.90)
   at java.lang.ClassLoader.loadClass(libgcj.so.90)
   at java.lang.ClassLoader.loadClass(libgcj.so.90)
   at java.lang.Class.forName(libgcj.so.90)
   at java.lang.Class.initializeClass(libgcj.so.90)
   ...3 more

Hmmm, that’s disappointing. I thought about it a minute, figured some guidance would be beneficial , so I sought out the best Java person on #drizzle IRC. Getting a name, but no response from an initial inquiry after about a half hour I thought again at the problem. Just what java are you using?

$ java -version
java version "1.5.0"
gij (GNU libgcj) version 4.3.3

$ ls -l /usr/bin/java
lrwxrwxrwx 1 root root 22 2009-07-17 12:36 /usr/bin/java -> /etc/alternatives/java

$ sudo find / -name java
[sudo] password for rbradfor:
/usr/lib/java
/usr/lib/ure/share/java
/usr/lib/jvm/java-6-sun-1.6.0.16/bin/java
/usr/lib/jvm/java-6-sun-1.6.0.16/jre/bin/java
/usr/lib/jvm/java-1.5.0-gcj-4.3-1.5.0.0/bin/java
/usr/lib/jvm/java-1.5.0-gcj-4.3-1.5.0.0/jre/bin/java
/usr/bin/java
/usr/include/c++/4.3/gnu/java
/usr/include/c++/4.3/java
/usr/local/include/google/protobuf/compiler/java

$ ls -l /etc/alternatives/j*
...
lrwxrwxrwx   1 root root    33 2009-09-17 17:50 jar -> /usr/lib/jvm/java-gcj/jre/bin/jar
lrwxrwxrwx   1 root root    39 2009-09-17 17:50 jar.1.gz -> /usr/lib/jvm/java-gcj/man/man1/jar.1.gz
lrwxrwxrwx   1 root root    35 2009-09-17 17:50 jarsigner -> /usr/lib/jvm/java-gcj/bin/jarsigner
lrwxrwxrwx   1 root root    45 2009-09-17 17:50 jarsigner.1.gz -> /usr/lib/jvm/java-gcj/man/man1/jarsigner.1.gz
lrwxrwxrwx   1 root root    34 2009-09-17 17:50 java -> /usr/lib/jvm/java-gcj/jre/bin/java
lrwxrwxrwx   1 root root    40 2009-09-17 17:50 java.1.gz -> /usr/lib/jvm/java-gcj/man/man1/java.1.gz
lrwxrwxrwx   1 root root    31 2009-09-17 17:50 javac -> /usr/lib/jvm/java-gcj/bin/javac
lrwxrwxrwx   1 root root    41 2009-09-17 17:50 javac.1.gz -> /usr/lib/jvm/java-gcj/man/man1/javac.1.gz
...

I wonder if I should use the real Sun Java.

$ sudo apt-get install sun-java6-jdk
Reading package lists... Done
Building dependency tree
Reading state information... Done
sun-java6-jdk is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 2 not upgraded.
$ sudo update-alternatives --config java

There are 4 alternatives which provide `java'.

  Selection    Alternative
-----------------------------------------------
          1    /usr/lib/jvm/java-6-sun/jre/bin/java
          2    /usr/bin/gij-4.3
          3    /usr/bin/gij-4.2
*+        4    /usr/lib/jvm/java-gcj/jre/bin/java

Press enter to keep the default[*], or type selection number: 1
Using '/usr/lib/jvm/java-6-sun/jre/bin/java' to provide 'java'.

$ ls -l /usr/bin/java
lrwxrwxrwx 1 root root 22 2009-07-17 12:36 /usr/bin/java -> /etc/alternatives/java
$ ls -l /etc/alternatives/java
lrwxrwxrwx 1 root root 36 2009-09-17 18:53 /etc/alternatives/java -> /usr/lib/jvm/java-6-sun/jre/bin/java

Yep, it took a minute to discover the update-alternatives command, lucky I didn’t try that manually.

A second try.

$ javac ExampleDrizzle.java
$ java ExampleDrizzle
Sep 17, 2009 6:54:22 PM org.drizzle.jdbc.internal.drizzle.DrizzleProtocol 
INFO: Connected to: localhost:4427
Sep 17, 2009 6:54:22 PM org.drizzle.jdbc.internal.drizzle.DrizzleProtocol close
INFO: Closing connection
Sep 17, 2009 6:54:22 PM org.drizzle.jdbc.internal.common.packet.AsyncPacketFetcher run
INFO: Connection closed

$ ~/drizzle/deploy/bin/drizzle test_java
Server version: 2009.09.1126 Source distribution (trunk)

drizzle> show tables;
+---------------------+
| Tables_in_test_java |
+---------------------+
| a                   |
+---------------------+
1 row in set (0 sec)

drizzle> desc a;
+-------+-------------+------+-----+---------+-------+
| Field | Type        | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| id    | int         | NO   | PRI | NULL    |       |
| value | varchar(20) | YES  |     | NULL    |       |
+-------+-------------+------+-----+---------+-------+
2 rows in set (0 sec)

And I’ve got a working testcase.