Description: This activity loads the Derby database engine using a simple Java JDBC program.
Keywords: WwdEmbedded.java program, running, CLASSPATH environment variable

# Activity 3: Run a JDBC program using the embedded driver

This activity loads the Derby database engine using a simple Java JDBC program.

This activity assumes that you have opened a command window and navigated to the `DERBYTUTOR` directory.
JDBC is the Java Database Connectivity API and is also the native API for Derby. The program uses the embedded driver to create the `jdbcDemoDB` database (if the database does not exist) and then connect to the database. You can then populate a table within the database with text. The program demonstrates some basic JDBC processing along with related error handling.

The Java compiler and runtime use the classpath, specified by the `CLASSPATH` environment variable, to locate the binary files (jar files and class files) that are needed to run Derby and other Java applications. Before performing this activity, you need to set the classpath and compile the `WwdEmbedded.java` program.

1. Copy the program files into the `DERBYTUTOR` directory and set the CLASSPATH environment variable.

   Operating System | Commands
   --- | ---
   UNIX (Korn Shell) |
       cp $DERBY_HOME/demo/programs/workingwithderby/* .

       export CLASSPATH=$DERBY_HOME/lib/derby.jar:.
   Windows |
       copy %DERBY_HOME%\demo\programs\workingwithderby\* .

       set CLASSPATH=%DERBY_HOME%\lib\derby.jar;.

   Important: Include the dot (`.`) at the end of each command so that your current working directory is included in the classpath and the files are copied to the correct location.
2. Compile the `WwdEmbedded.java` program.

       javac WwdEmbedded.java

   Important: A command prompt appears if the compilation is successful. The binary file `WwdEmbedded.class` is created. If an error message appears, verify that the JDK is properly installed.
3. Run the program. The `WwdEmbedded.java` program populates a table with wish-list items. The program prompts you for text input (up to 32 characters), stores the text input in a database table, and then lists the items stored in the table. The program continues to ask for wish-list items until the you type the command `exit` or a problem is encountered. Some basic information on program progress is displayed at the beginning and the end of the program.

       java WwdEmbedded
       org.apache.derby.jdbc.EmbeddedDriver loaded.
       Connected to database jdbcDemoDB
        . . . . creating table WISH_LIST
       Enter wish-list item (enter exit to end):
       a peppermint stick
         __________________________________________________________
       On 2007-05-04 15:16:16.795 I wished for a peppermint stick
         __________________________________________________________
       Enter wish-list item (enter exit to end):
       an all expenses paid vacation
         __________________________________________________________
       On 2007-05-04 15:16:16.795 I wished for a peppermint stick
       On 2007-05-04 15:16:46.875 I wished for an all expenses paid vacation
         __________________________________________________________
       Enter wish-list item (enter exit to end):
       exit
       Closed connection
       Database shut down normally
       Working With Derby JDBC program ending.

- The WwdEmbedded program
  This section describes the WwdEmbedded.java program, highlighting details specific to accessing a Derby database from a JDBC program.

Parent topic: Self-study tutorial for users new to Derby