org.jadetower.sql.impl
Class VelocitySQLEvaluator

java.lang.Object
  org.jadetower.sql.impl.VelocitySQLEvaluator

All Implemented Interfaces:

SQLEvaluator

public class VelocitySQLEvaluator

extends java.lang.Object

implements SQLEvaluator

An SQLEvaluator that uses Jakarta Velocity templates for SQL statement creation.

Field Summary

static java.lang.String	BIND_PARAMETERS
static java.lang.String	SQL_KEY

Constructor Summary

VelocitySQLEvaluator(java.io.Reader reader)
creates a new SQLEvalutor.

Method Summary

void	clearContext() clears the Velocity Context and creates a new one.
void	close() attempts to close all result sets and prepared statements
java.sql.ResultSet	executeQuery(java.sql.Connection dbCon) executes the query using the velocity template and a JDBC PreparedStatement
java.util.Collection	executeQuery(java.sql.Connection dbCon, java.lang.Class beanClazz, java.util.Map map) executes query and maps results to a collection of type "beanClazz".
int	executeUpdate(java.sql.Connection dbCon) executes INSERT, UPDATE, or DELETE statements
java.lang.String	getSQL() Returns the SQL statement by evaluating a Velocity template.
protected void	initVelocity() initialized Velocity runtime
boolean	isSQLMutable() returns SQL mutability state.
void	set(java.lang.String key, java.lang.Object value) sets a value in the Velocity context
void	setContext(java.util.Map map) puts all values of the map into the context.
protected void	setReader(java.io.Reader reader) sets the template reader.
void	setSQLMutable(boolean mutable) sets the mutability for SQL statements.
protected void	setVelocityContext(org.apache.velocity.VelocityContext context) sets the Velocity context

Methods inherited from class java.lang.Object

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

Field Detail

BIND_PARAMETERS

public static final java.lang.String BIND_PARAMETERS

See Also:

Constant Field Values

SQL_KEY

public static final java.lang.String SQL_KEY

See Also:

Constant Field Values

Constructor Detail

VelocitySQLEvaluator

public VelocitySQLEvaluator(java.io.Reader reader)

creates a new SQLEvalutor.

Parameters:

reader - a reader to the Velocity template for the query.

Method Detail

set

public void set(java.lang.String key,
                java.lang.Object value)

sets a value in the Velocity context

Specified by:

set in interface SQLEvaluator

Parameters:

key - context key

value - context value

setContext

public void setContext(java.util.Map map)

puts all values of the map into the context. Map keys should be of type String or they will be ignored. This method overrides any other values set by the set(String key, Object value) method.

Specified by:

setContext in interface SQLEvaluator

Parameters:

map - context map

getSQL

public java.lang.String getSQL()
                        throws java.sql.SQLException

Returns the SQL statement by evaluating a Velocity template.

Specified by:

getSQL in interface SQLEvaluator

Returns:

SQL statement

Throws:

java.sql.SQLException - thrown if error created during template parsing

executeQuery

public java.sql.ResultSet executeQuery(java.sql.Connection dbCon)
                                throws java.sql.SQLException

executes the query using the velocity template and a JDBC PreparedStatement

Specified by:

executeQuery in interface SQLEvaluator

Parameters:

dbCon - the database connection

Returns:

a JDBC ResultSet

Throws:

java.sql.SQLException - thrown if JDBC or Template parsing error occurs

executeQuery

public java.util.Collection executeQuery(java.sql.Connection dbCon,
                                         java.lang.Class beanClazz,
                                         java.util.Map map)
                                  throws java.sql.SQLException

executes query and maps results to a collection of type "beanClazz". Uses Jakarta BeanUtils for mapping.

Specified by:

executeQuery in interface SQLEvaluator

Parameters:

dbCon - the JDBC database connection

beanClazz - a Java Bean class

map - an alternate Column to Bean property mapping

Returns:

a collection of type "beanClazz"

Throws:

java.sql.SQLException - thrown if JDBC, query parsing, or bean mapping error occurs

See Also:

SQLEvaluator

executeUpdate

public int executeUpdate(java.sql.Connection dbCon)
                  throws java.sql.SQLException

executes INSERT, UPDATE, or DELETE statements

Specified by:

executeUpdate in interface SQLEvaluator

Parameters:

dbCon - a JDBC connection

Returns:

number of effected rows

Throws:

java.sql.SQLException - thrown if JDBC or sql parsing error occurs

setReader

protected void setReader(java.io.Reader reader)

sets the template reader. can only be set once

Parameters:

reader - a reader to the template

setVelocityContext

protected void setVelocityContext(org.apache.velocity.VelocityContext context)

sets the Velocity context

Parameters:

context - a VelocityContext object

initVelocity

protected void initVelocity()
                     throws java.lang.Exception

initialized Velocity runtime

Throws:

java.lang.Exception - thrown if error initializing Velocity occurs

setSQLMutable

public void setSQLMutable(boolean mutable)

sets the mutability for SQL statements. Allows for caching of statements.

Specified by:

setSQLMutable in interface SQLEvaluator

Parameters:

mutable - if false, SQL statements will be cached and updates to the context ignored.

isSQLMutable

public boolean isSQLMutable()

returns SQL mutability state. Defaults to 'true'.

Specified by:

isSQLMutable in interface SQLEvaluator

Returns:

mutability

See Also:

SQLEvaluator.setSQLMutable(boolean mutable)

clearContext

public void clearContext()

clears the Velocity Context and creates a new one. If not mutable, this method does nothing.

Specified by:

clearContext in interface SQLEvaluator

close

public void close()
           throws java.sql.SQLException

attempts to close all result sets and prepared statements

Specified by:

close in interface SQLEvaluator

Throws:

java.sql.SQLException - thrown if error during close