com.pow2.dao
Class AbstractDAO

java.lang.Object
  com.pow2.dao.AbstractDAO

Direct Known Subclasses:

DAO, DBUserDAO, HTMLDAO, IdGenerator, QueryDAO, ResultSetDataListImpl

public abstract class AbstractDAO

extends Object

Abstract Data access object.

Version:

$Id: AbstractDAO.java,v 1.1.1.1 2004/08/31 20:22:46 foxat Exp $

Author:

Luca Fossato

Field Summary

protected static org.apache.log4j.Category

cat Log4J category.

Constructor Summary

protected

AbstractDAO() Protected default constructor.

Method Summary

boolean	assertion(String tableName, String condition) Apply the input condition on the input table.
protected void	closeResources(Connection con, boolean commit) Commit or rollback any uncommitted transaction and close the input connection.
protected void	closeResources(ResultSet rs, Statement st, Connection con, boolean commit) Close the JDBC resultSet and statement objects, commit or rollback any uncommitted transaction and close the input connection.
protected void	closeResources(Statement st, Connection con, boolean commit) Close the JDBC statement object, commit or rollback any uncommitted transaction and close the input connection.
long	count(String tableName) Get the number of records from the input table.
long	count(String tableName, String condition) Get the number of records from the input table
void	delete(String tableName, String condition) Delete records from the input table, using the input condition.
void	delete(String tableName, String condition, Connection con) Delete records from the input table, using the input condition.
protected String	encode(String statement) Encode the input statement string, replacing all the "'" characters with "''" string.
Connection	getConnection() Return a JDBC Connection.
Connection	getConnection(int isolationLevel) Open a new transaction and return a JDBC Connection set with the input isolation level.
long	getNewKey() Get a new unique key value.
boolean	isDebugEnabled() Get the debug status.
protected void	populate(Object bean, ResultSet resultSet) Transfer a record data into the input value object bean.
protected String	setLike(String value) set a SQL LIKE statement
protected String	setLike(String value, boolean upperCase, int likeMode) set a SQL LIKE statement

Methods inherited from class java.lang.Object

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

Field Detail

cat

protected static org.apache.log4j.Category cat

Log4J category.

Constructor Detail

AbstractDAO

protected AbstractDAO()

Protected default constructor.

Method Detail

isDebugEnabled

public boolean isDebugEnabled()

Get the debug status.

Returns:

the debug status. True means that all the logging requests of priority DEBUG are enabled; false means that that logging requests are are disabled

assertion

public boolean assertion(String tableName,
                         String condition)
                  throws Exception

Apply the input condition on the input table.

Parameters:

tableName - the name of the table where to apply the input condition

condition - the where condition string

Returns:

true if the input condition retrieves at least one record from the input table; false otherwise

Throws:

Exception - if any error occurs

count

public long count(String tableName)
           throws Exception

Get the number of records from the input table.

Parameters:

tableName - the name of the table where to retrieve the records number

Returns:

the number of records of the input table

Throws:

Exception - if any error occurs

count

public long count(String tableName,
                  String condition)
           throws Exception

Get the number of records from the input table

Parameters:

tableName - the name of the table where to retrieve the records number

condition - the where condition string, or null (stands for "no condition")

Returns:

the records number of the input table

Throws:

Exception - if any error occurs

getNewKey

public long getNewKey()
               throws Exception

Get a new unique key value.

Returns:

a new unique key value

Throws:

Exception - Description of the Exception

delete

public void delete(String tableName,
                   String condition)
            throws Exception

Delete records from the input table, using the input condition.
This method supports the READ_COMMITTED isolation level to prevent dirty reads.

Parameters:

condition - the query string.

tableName - Description of the Parameter

Throws:

Exception - Description of the Exception

delete

public void delete(String tableName,
                   String condition,
                   Connection con)
            throws Exception

Delete records from the input table, using the input condition.
This method is useful for DbForms interceptor classes, because it doesn't close the connection object; the connection management is left to the application developer.

Parameters:

tableName - the name of the database table

condition - the query condition (a SQL 'where' clause without the 'WHERE' word);

con - the JDBC Connection object.

Throws:

Exception - if any error occurs

getConnection

public Connection getConnection()
                         throws Exception

Return a JDBC Connection.
note: should
NOT
be public !!

Returns:

a JDBC Connection

Throws:

Exception - Exception if any error occurs

getConnection

public Connection getConnection(int isolationLevel)
                         throws Exception

Open a new transaction and return a JDBC Connection set with the input isolation level.

Parameters:

isolationLevel - the isolation level to set the connection to

Returns:

the new "transactional" connection object

Throws:

Exception - if any error occurs

setLike

protected String setLike(String value)

set a SQL LIKE statement

Parameters:

value - the value to bound to the LIKE statement

Returns:

the LIKE statement

setLike

protected String setLike(String value,
                         boolean upperCase,
                         int likeMode)

set a SQL LIKE statement

Parameters:

value - the value to bound to the LIKE statement

upperCase - true to upper all the characters of the the input value string

likeMode - 0 stands for "contains": LIKE %${value}% 1 stands for "starts with": LIKE ${value}%

Returns:

the LIKE statement

encode

protected String encode(String statement)

Encode the input statement string, replacing all the "'" characters with "''" string.

Parameters:

statement - the SQL statement string to encode

Returns:

the encoded statement string

populate

protected void populate(Object bean,
                        ResultSet resultSet)
                 throws SQLException

Transfer a record data into the input value object bean.
The bean must simply have one or more accessors that match column names in the Map object generated from the input resultSet.
The columns that have a matching accessor will be used to populate the beans. Other accessors and columns are ignored.

Parameters:

bean - the value object to populate with the data retrieved from the input resultSet

resultSet - the resultSet used to retrieve the record data from

Throws:

SQLException - if any error occurs

closeResources

protected void closeResources(Connection con,
                              boolean commit)
                       throws SQLException

Commit or rollback any uncommitted transaction and close the input connection.
Call this method into a finally() clause.

Parameters:

con - the Connection object to close

commit - true to commit the transaction, false to rollback it

Throws:

SQLException - if any error occurs

closeResources

protected void closeResources(Statement st,
                              Connection con,
                              boolean commit)
                       throws SQLException

Close the JDBC statement object, commit or rollback any uncommitted transaction and close the input connection.
Call this method into a finally() clause.

Parameters:

st - the Statement object to close

con - the Connection object to close

commit - true to commit the transaction, false to rollback it

Throws:

SQLException - if any error occurs

closeResources

protected void closeResources(ResultSet rs,
                              Statement st,
                              Connection con,
                              boolean commit)
                       throws SQLException

Close the JDBC resultSet and statement objects, commit or rollback any uncommitted transaction and close the input connection.
Call this method into a finally() clause.

Parameters:

rs - the recordSet object to close

con - the Connection object to close

st - the statement object to close

commit - true to commit the connection, false to rollback it

Throws:

SQLException - if any error occurs