org.xerial.db.sql
Class DatabaseAccessBase

java.lang.Object
  org.xerial.db.sql.DatabaseAccessBase

All Implemented Interfaces:

DatabaseAccess

Direct Known Subclasses:

MySQLAccess, PostgresAccess, SQLiteAccess

public class DatabaseAccessBase
extends Object
implements DatabaseAccess

A base implementation of the DatabaseAccess interface.

Author:

leo

Constructor Summary

DatabaseAccessBase(ConnectionPool connectionPool)

Method Summary

<T> T	accumulate(String sql, ResultSetHandler<T> handler) Accumulate the query result within the ResultSetHandler, then return the result from the handler
protected Statement	createStatement(Connection connection)
protected String	createValueTupleFromBean(String tableName, Object bean) Align the content of a bean object so that it matches with the corresponding relation (table schema) For example, give a bean class, e.g.
void	dispose() Close all connections managed by this database access
ConnectionPool	getConnectionPool()
Relation	getRelation(String tableName) Gets the relation (schema) information of the table.
List<String>	getTableNameList() Gets the table names contained in this database.
<T> int	insert(String tableName, T bean) Inserts a bean into a table
<T> void	query(String sql, BeanResultHandler<T> beanResultHandler) Performs an SQL query, while consuming the results with the given handler
<T> List<T>	query(String sql, Class<T> resultRowType) perforam a given SQL query, then output its results
<T> void	query(String sql, ResultSetHandler<T> pullHandler) Performs an SQL query, while consuming the results with the given handler
<T> List<T>	queryWithHandler(String sql, ResultSetHandler<T> handler)
void	setAutoCommit(boolean enableAutoCommit) Enable/disable auto commit mode for all subsequent queries.
void	setQueryTimeout(int sec) Sets the time of the query until it will be terminated in seconds
<T> List<T>	singleColumnQuery(String sql, String targetColumn, Class<T> resultColumnType) Retrieves only the single column from the SQL query result
<T> void	toJSON(String sql, Class<T> beanClass, Writer writer)
int	update(String sql) Performs the update query
int	update(String sql, boolean autoCommit) Performs the update query
int	updateWithPreparedStatement(String sqlForPreparedStatement, PreparedStatementHandler handler) Performs the update using prepared statement.

Methods inherited from class java.lang.Object

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

Constructor Detail

DatabaseAccessBase

public DatabaseAccessBase(ConnectionPool connectionPool)
                   throws DBException

Throws:

DBException

Method Detail

dispose

public void dispose()
             throws DBException

Description copied from interface: DatabaseAccess

Close all connections managed by this database access

Specified by:

dispose in interface DatabaseAccess

Throws:

DBException

createStatement

protected Statement createStatement(Connection connection)
                             throws SQLException

Throws:

SQLException

query

public <T> List<T> query(String sql,
                         Class<T> resultRowType)
              throws DBException

perforam a given SQL query, then output its results

Specified by:

query in interface DatabaseAccess

Type Parameters:

T - row type : Bean class type

Parameters:

sql - sql statement

resultRowType - it must be equal to the T

result -

Throws:

DBException

query

public <T> void query(String sql,
                      ResultSetHandler<T> pullHandler)
           throws DBException

Description copied from interface: DatabaseAccess

Performs an SQL query, while consuming the results with the given handler

Specified by:

query in interface DatabaseAccess

Parameters:

sql - the SQL query expression

pullHandler - the result set handler that consumes the result set of the query.

Throws:

DBException

queryWithHandler

public <T> List<T> queryWithHandler(String sql,
                                    ResultSetHandler<T> handler)
                         throws DBException

Throws:

DBException

accumulate

public <T> T accumulate(String sql,
                        ResultSetHandler<T> handler)
             throws DBException

Accumulate the query result within the ResultSetHandler, then return the result from the handler

Specified by:

accumulate in interface DatabaseAccess

Type Parameters:

T -

Parameters:

sql -

handler -

Returns:

Throws:

DBException

updateWithPreparedStatement

public int updateWithPreparedStatement(String sqlForPreparedStatement,
                                       PreparedStatementHandler handler)
                                throws DBException

Description copied from interface: DatabaseAccess

Performs the update using prepared statement. You can set the tuple values in the PreparedStatementHandler via PreparedStatement.setBytes(int, byte[]), etc.

Specified by:

updateWithPreparedStatement in interface DatabaseAccess

Parameters:

sqlForPreparedStatement - the update SQL statement that may contain '?' mark that will be filled in the PreparedStatementHandler

handler - the handler for filling '?' marks in the sql statement

Returns:

Throws:

DBException

update

public int update(String sql)
           throws DBException

Description copied from interface: DatabaseAccess

Performs the update query

Specified by:

update in interface DatabaseAccess

Parameters:

sql - the update SQL query

Returns:

the number of rows updated

Throws:

DBException

update

public int update(String sql,
                  boolean autoCommit)
           throws DBException

Description copied from interface: DatabaseAccess

Performs the update query

Specified by:

update in interface DatabaseAccess

Parameters:

sql - the update SQL query

autoCommit - true when enable auto commit arounc this update query, false otherwise

Returns:

the number of rows updated

Throws:

DBException

getConnectionPool

public ConnectionPool getConnectionPool()

setAutoCommit

public void setAutoCommit(boolean enableAutoCommit)

Description copied from interface: DatabaseAccess

Enable/disable auto commit mode for all subsequent queries.

Specified by:

setAutoCommit in interface DatabaseAccess

setQueryTimeout

public void setQueryTimeout(int sec)

Description copied from interface: DatabaseAccess

Sets the time of the query until it will be terminated in seconds

Specified by:

setQueryTimeout in interface DatabaseAccess

Parameters:

sec - timeout (sec.)

getRelation

public Relation getRelation(String tableName)
                     throws DBException

Description copied from interface: DatabaseAccess

Gets the relation (schema) information of the table.

Specified by:

getRelation in interface DatabaseAccess

Parameters:

tableName - the target table name

Returns:

the relation of the table

Throws:

DBException

getTableNameList

public List<String> getTableNameList()
                              throws DBException

Description copied from interface: DatabaseAccess

Gets the table names contained in this database.

Specified by:

getTableNameList in interface DatabaseAccess

Returns:

the list of table names

Throws:

DBException

singleColumnQuery

public <T> List<T> singleColumnQuery(String sql,
                                     String targetColumn,
                                     Class<T> resultColumnType)
                          throws DBException

Description copied from interface: DatabaseAccess

Retrieves only the single column from the SQL query result

Specified by:

singleColumnQuery in interface DatabaseAccess

targetColumn - the target column

resultColumnType - the target column type to be transformed

Returns:

the list of the specified column data

Throws:

DBException

query

public <T> void query(String sql,
                      BeanResultHandler<T> beanResultHandler)
           throws DBException

Description copied from interface: DatabaseAccess

Performs an SQL query, while consuming the results with the given handler

Specified by:

query in interface DatabaseAccess

Throws:

DBException

insert

public <T> int insert(String tableName,
                      T bean)
           throws DBException

Description copied from interface: DatabaseAccess

Inserts a bean into a table

Specified by:

insert in interface DatabaseAccess

Returns:

the number of rows updated (1 if succeeded)

Throws:

DBException

createValueTupleFromBean

protected String createValueTupleFromBean(String tableName,
                                          Object bean)
                                   throws DBException,
                                          BeanException

Align the content of a bean object so that it matches with the corresponding relation (table schema) For example, give a bean class, e.g. class Person { int id; String name; (getters are ommited) } and a table named person with a schema 'id, name', the createValueTupleFromBean("person", (a Person object)) will give a tuple representation of the Person object (id=1, name="leo"), that is '1,"leo"'. This returned string can be used as it is within an insert statement of the SQL, i.e., insert into person values(1, "leo")

Parameters:

tableName -

bean -

Returns:

Throws:

DBException

InvalidBeanException

BeanException

toJSON

public <T> void toJSON(String sql,
                       Class<T> beanClass,
                       Writer writer)
            throws DBException,
                   IOException

Specified by:

toJSON in interface DatabaseAccess

Throws:

DBException

IOException