org.apache.cayenne.access.jdbc
Class ResultDirective

java.lang.Object
  org.apache.velocity.runtime.directive.Directive
      org.apache.cayenne.access.jdbc.ResultDirective

All Implemented Interfaces:

java.lang.Cloneable, org.apache.velocity.runtime.directive.DirectiveConstants

public class ResultDirective
extends org.apache.velocity.runtime.directive.Directive

A custom Velocity directive to describe a ResultSet column. There are the following possible invocation formats inside the template:

 #result(column_name) - e.g. #result('ARTIST_ID')
 #result(column_name java_type) - e.g. #result('ARTIST_ID' 'String')
 #result(column_name java_type column_alias) - e.g. #result('ARTIST_ID' 'String' 'ID')
 #result(column_name java_type column_alias data_row_key) - e.g. #result('ARTIST_ID' 'String' 'ID' 'toArtist.ID')
 

'data_row_key' is needed if SQL 'column_alias' is not appropriate as a DataRow key on the Cayenne side. One common case when this happens is when a DataRow retrieved from a query is mapped using joint prefetch keys. In this case DataRow must use DB_PATH expressions for joint column keys, and their format is incompatible with most databases alias format.

Most common Java types used in JDBC can be specified without a package. This includes all numeric types, primitives, String, SQL dates, BigDecimal and BigInteger.

Since:

1.1

Author:

Andrei Adamchik

Field Summary

Fields inherited from class org.apache.velocity.runtime.directive.Directive

rsvc

Fields inherited from interface org.apache.velocity.runtime.directive.DirectiveConstants

BLOCK, LINE

Constructor Summary

ResultDirective()

Method Summary

protected void	bindResult(org.apache.velocity.context.InternalContextAdapter context, ColumnDescriptor columnDescriptor) Adds value to the list of result columns in the context.
protected java.lang.Object	getChild(org.apache.velocity.context.InternalContextAdapter context, org.apache.velocity.runtime.parser.node.Node node, int i)
protected java.lang.String	getChildAsString(org.apache.velocity.context.InternalContextAdapter context, org.apache.velocity.runtime.parser.node.Node node, int i) Returns a directive argument at a given index converted to String.
java.lang.String	getName()
int	getType()
protected java.lang.String	guessType(java.lang.String type) Converts "short" type notation to the fully qualified class name.
boolean	render(org.apache.velocity.context.InternalContextAdapter context, java.io.Writer writer, org.apache.velocity.runtime.parser.node.Node node)

Methods inherited from class org.apache.velocity.runtime.directive.Directive

getColumn, getLine, init, setLocation

Methods inherited from class java.lang.Object

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

Constructor Detail

ResultDirective

public ResultDirective()

Method Detail

getName

public java.lang.String getName()

Specified by:

getName in class org.apache.velocity.runtime.directive.Directive

getType

public int getType()

Specified by:

getType in class org.apache.velocity.runtime.directive.Directive

render

public boolean render(org.apache.velocity.context.InternalContextAdapter context,
                      java.io.Writer writer,
                      org.apache.velocity.runtime.parser.node.Node node)
               throws java.io.IOException,
                      org.apache.velocity.exception.ResourceNotFoundException,
                      org.apache.velocity.exception.ParseErrorException,
                      org.apache.velocity.exception.MethodInvocationException

Specified by:

render in class org.apache.velocity.runtime.directive.Directive

Throws:

java.io.IOException

org.apache.velocity.exception.ResourceNotFoundException

org.apache.velocity.exception.ParseErrorException

org.apache.velocity.exception.MethodInvocationException

getChild

protected java.lang.Object getChild(org.apache.velocity.context.InternalContextAdapter context,
                                    org.apache.velocity.runtime.parser.node.Node node,
                                    int i)
                             throws org.apache.velocity.exception.MethodInvocationException

Throws:

org.apache.velocity.exception.MethodInvocationException

getChildAsString

protected java.lang.String getChildAsString(org.apache.velocity.context.InternalContextAdapter context,
                                            org.apache.velocity.runtime.parser.node.Node node,
                                            int i)
                                     throws org.apache.velocity.exception.MethodInvocationException

Returns a directive argument at a given index converted to String.

Throws:

org.apache.velocity.exception.MethodInvocationException

Since:

1.2

guessType

protected java.lang.String guessType(java.lang.String type)

Converts "short" type notation to the fully qualified class name. Right now supports all major standard SQL types, including primitives. All other types are expected to be fully qualified, and are not converted.

bindResult

protected void bindResult(org.apache.velocity.context.InternalContextAdapter context,
                          ColumnDescriptor columnDescriptor)

Adds value to the list of result columns in the context.