com.caplin.transformer.persistence

Class JdbcPersistorImpl

java.lang.Object

com.caplin.transformer.persistence.JdbcPersistorImpl

All Implemented Interfaces:

Persistor

public class JdbcPersistorImpl
extends Object
implements Persistor

A basic JDBC Implementation of a Persistor. This implementation expects the user to provide the following configuration in Transformers persistence.conf configuration file

 persistence.conf
     
          persistence-classid com/caplin/transformer/persistence/JdbcPersistorImpl
          add-database-params
              init-string    <jdbc url>
              driver-name    <jdbc driver - must be explicitly added to transformers jvm-global-classpath>
              username       <db user>
              password       <db password>
              extra-params   <timeout in seconds for Connection.isValid()>
          end-database-params
     
 

 java.conf
     
          jvm-global-classpath <path_to_jdbc_driver>
      end-database-params
     
 

Constructor Summary

Constructors

Constructor and Description
JdbcPersistorImpl(PersistorConfiguration configuration, Logger logger)

Method Summary

Modifier and Type	Method and Description
int	onDelete(String table, Map<String,String> selector) Delete one or more rows from a table
List<Map<String,String>>	onQuery(String table, String query, QueryParams params) Query the database for results.
void	onShutdown() Called when transformer shuts down to close open connections and release acquired resources
int	onUpsert(String table, Map<String,String> keys, Map<String,String> data) Implement this method to handle update or insert callbacks.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

JdbcPersistorImpl

public JdbcPersistorImpl(PersistorConfiguration configuration,
                         Logger logger)
                  throws Exception

Throws:

Exception

Method Detail

onUpsert

public int onUpsert(String table,
                    Map<String,String> keys,
                    Map<String,String> data)

Description copied from interface: Persistor

Implement this method to handle update or insert callbacks. This method is expected to update an existing row or insert a new one if the update did not affect any rows

This method should attempt to update an existing row first by setting all the values given in data and using the entries of this map where the key matches key anded together in the where clause like: "key1=value1 and key2=value2". If the update did not affect any rows, then an insert should be executed with the data given

Specified by:

onUpsert in interface Persistor

Parameters:

table - The table to be modified

keys - Map containing column/value pairs to be used in the where clause for updates. If no row matches the criteria, a combination of keys and data is used as data for the rows, where entries in data take precedence over entries in keys

data - Map containing column/value pairs to be set in the row identified by keys

Returns:

-1 on error or >=0 affected rows on success

onQuery

public List<Map<String,String>> onQuery(String table,
                                        String query,
                                        QueryParams params)

Description copied from interface: Persistor

Query the database for results.

Queries the database with query being a valid sql selection and args being a list of arguments that get bound to ? in the query string

Specified by:

onQuery in interface Persistor

Parameters:

table - The table name to execute the query on.

query - a valid sql where clause or an empty string for all rows.

params - QueryParams to be used for the query

Returns:

null on error, an empty array if there were no results or an array holding all the rows returned by the query.

onDelete

public int onDelete(String table,
                    Map<String,String> selector)

Description copied from interface: Persistor

Delete one or more rows from a table

Delete rows where the all the columns specified in selector match their specified values

Specified by:

onDelete in interface Persistor

Parameters:

table - The table name to delete from.

selector - Map of column names (keys) and values to be anded together in the where clause.

Returns:

true if the operation affected more than 0 rows, false otherwise.

onShutdown

public void onShutdown()

Description copied from interface: Persistor

Called when transformer shuts down to close open connections and release acquired resources

Specified by:

onShutdown in interface Persistor