Jdbc Module
Jdbc Module
The Jdbc Module creates 2-tier, Jdbc implementations of the JBeans Session and Home interfaces.
The Jdbc Module contains the following classes:-
- com.javelin.generator.jdbc.JdbcSessionClassWriter
- com.javelin.generator.jdbc.JdbcHomeClassWriter
- com.javelin.generator.jdbc.JdbcContextPropertiesWriter
In order to use the Jdbc module you need to include the following writer:
$GENERATOR.AggregateWriter jdbc
Class Hierarchy
The top-level Jdbc Writer class hierarchy is illustrated below: -
Jdbc Properties
| Property Name |
Default Value |
Example |
Description |
| driver |
MANDITORY |
sun.jdbc.odbc.JdbcOdbcDriver |
The driver class name. |
| url |
MANDITORY |
jdbc:odbc:DEMO |
The database URL – not including the username and password. |
| user |
"" |
myname |
Defaults to an empty string. |
| password |
"" |
password |
Defaults to an empty string. |
| minConnections |
1 |
10 |
The minConnections is the resting state for the connection pool. If more than minConnections are opened then when a connection is returned it is closed. |
| maxConnections |
1 |
20 |
The maximum number of connections that can be opened. |
| waitTimeout |
5000 |
5000 |
The number of milliseconds to wait for a connection to become available. A range can be specified 5000-10000, which will randomise within that range. |
| usageLogged |
false |
true |
Are the first/last dates and usage logged;"true" or "false" |
| debugConnections |
false |
true |
Write the allocation and deallocation to the output stream;"true" or "false" |
| debugTransactions |
false |
true |
Write the allocation and deallocation to the output stream;"true" or "false" |
| debugDriver |
false |
true |
Write the DriverManager Log Stream to the System.out;"true" or "false" |
| verbose |
false |
true |
Write selected output from the code to the System.out;"true" or "false" |
| catalog |
null |
mycatalog |
This sets the catalog property to null. |
| readOnly |
false |
true |
"true" or "false" |
| autoCommit |
false |
true |
"true" or "false" |
| transactionIsolation |
TRANSACTION_NONE |
TRANSACTION_READ_ UNCOMMITTED |
Possible String values are taken from the java.sql.Connection class. One of: - TRANSACTION_NONE TRANSACTION_READ_UNCOMMITTED TRANSACTION_READ_COMMITTED TRANSACTION_REPEATABLE_READ TRANSACTION_SERIALIZABLE |
| currentDate |
CURRENT_DATE |
GetDate() |
The default syntax for the current date for the database. |
| currentTime |
CURRENT_TIME |
GetDate() |
The default syntax for the current time for the database. |
| currentTimeStamp |
CURRENT_TIMESTAMP |
GetDate() |
The default syntax for the current time stamp for the database. |
| dateFormat |
dd/MM/yyyy |
dd/MM/yyyy |
The default date format for the database. |
| timeFormat |
kk:mm:ss |
kk:mm:ss |
The default time format for the database. |
| dateTimeFormat |
dd/MM/yyyy kk:mm:ss |
yyyy-MM-dd-kk.mm.ss.SSS |
The default datetime format for the database. |
| fatalStates |
s1,s2,s2 |
A comma separated list of SQLException states, that will close a connection. |
|
| driverPropertiesPath |
null |
subpackage/mydriver.properties |
The relative class path plus the name of the properties file, to the relative class. If the driver properties file is in a subdirectory called xyz. Then this property would be "xyz/mydriver.properties" |
| batchSize |
100 |
10 |
The default batch size for the JdbcTableKey. This states how often the batch of primary keys is updated. |
| tableKeyClass |
com.javelin.util.jdbc.JdbcTableKey |
A subclass of JdbcTableKey for a specific source. This * allows custom key generation for a specific source. |
For example:
<dbname>.driver=com.inet.tds.TdsDriver
<dbname>.url=jdbc:inetdae:localhost:1433?database=<dbname>&sql7=true
#<dbname>.driverPropertiesPath=
<dbname>.user=<userName>
<dbname>.password=<password>
<dbname>.transactionIsolation=TRANSACTION_READ_COMMITTED
<dbname>.readOnly=false
<dbname>.autoCommit=false
<dbname>.maxConnections=2
<dbname>.minConnections=1
<dbname>.waitTimeout=5000
<dbname>.keyBatchSize=10
#<dbname>.tableKeyClass=com.javelin.util.jdbc.JdbcTableKey
<dbname>.usageLogged=false
<dbname>.debugTransactions=false
<dbname>.debugConnections=false
<dbname>.dateFormat=dd/MM/yyyy
<dbname>.timeFormat=kk:mm:ss
<dbname>.timeStampFormat=yyyy-MM-dd-kk.mm.ss.SSS
<dbname>.currentDate=GetDate()
<dbname>.currentTime=GetDate()
<dbname>.currentTimeStamp=GetDate()
#<dbname>.debugDriver=true
Custom Connection Pool and User Transaction
If you want to use your own connection pool
JdbcHome.getConnection=java code.
This code is written inside a method with the signature:
protected Connection getConnection() throws SQLException
The UserTransaction may also need managing if you want to use your own UserTransaction.
ContextProperties.newUserTransaction=java code.
This code is written inside a method with the signature:
protected UserTransaction newUserTransaction() throws SQLException
Abstract Jdbc Writer (com.javelin.generator.jdbc.AbstractJdbcWriter)
The Abstract Jdbc Writer has the following methods: -
- public String getJdbcHomeClassName()
- public String getJdbcSessionClassName()
- public String getContextPropertiesClassName()
Jdbc Session Class Writer (com.javelin.generator.jdbc.JdbcSessionClassWriter)
The Jdbc Session Class Writer creates BeanSessions that persists beans to a Jdbc storage.
The Sessions are created in the Jdbc package, with the name pattern: -
Jdbc<ClassName>Session
JdbcSessions are responsible for persisting dependent graphs of Beans. JdbcSessions defer loading, finding and counting beans to the JdbcHome classes.
By default the classes generated have the name and pattern: -
$JDBCSESSION=public class $PACKAGE.jdbc.$THIS extends $BEANS.jdbc.JdbcSession implements $PACKAGE
Jdbc Home Class Writer (com.javelin.generator.jdbc.JdbcHomeClassWriter)
The Jdbc Home Class Writer creates BeanHomes.
The Homes are created in the jdbc package, with the name pattern: -
Jdbc<ClassName>Home
JdbcHomes are responsible for persisting, loading, finding and counting individual Beans from a Jdbc store. The Jdbc Home classes currently use the JPool jdbc pooling package to pool connections.
By default the classes generated have the name and pattern: -
$JDBCHOME=public class $PACKAGE.jdbc.$THIS extends $BEANS.jdbc.JdbcHome implements $PACKAGE
Jdbc Context Properties Writer (com.javelin.generator.jdbc.JdbcContextPropertiesWriter)
The Jdbc Context Properties Writer creates a Context Properties file in the jdbc package, with the name: -
JdbcContextProperties
The JdbcContextProperties class is responsible for binding the JBeans interface names to implementations. The binding patterns are as follows: -
<packageName>.<ClassName>=<packageName>.<ClassName>
<packageName>.<ClassName>=<packageName>.Lazy<ClassName>
<packageName>.<ClassName>Session=<packageName>.jdbc.Jdbc<ClassName>Session
<packageName>.<ClassName>Home=<packageName>.jdbc.Jdbc<ClassName>Home
<packageName>.<ClassName>Validator =<packageName>.<ClassName>Validator
To override the bindings in the jdbc properties class do the following: -
<ClassName>.jdbc.Object=<fully qualified class
name>
<ClassName>.jdbc.Bean=<fully qualified class
name>
<ClassName>.jdbc.Session=<fully qualified class name>
<ClassName>.jdbc.Home=<fully qualified class name>
<ClassName>.jdbc.Validator=<fully qualified class name>