org.apache.jdo.jdoql.tree
Interface FieldAccessExpression

All Superinterfaces:

Expression, IdentifierExpression, Node, java.io.Serializable

All Known Implementing Classes:

FieldAccessExpr

public interface FieldAccessExpression

extends IdentifierExpression

This node represents a field access expression. Field access expression have exactly one child, the target expression. This expression can be an arbitrary expression.

Author:

Michael Watzek

Method Summary

java.lang.Object	getFieldValue(javax.jdo.PersistenceManager pm, java.lang.Object object) Returns the value of the field corresponding with this field access expression for the argument object.
Expression	getTarget() Returns the target expression of this field access.

Methods inherited from interface org.apache.jdo.jdoql.tree.IdentifierExpression

getName, getTypeName

Methods inherited from interface org.apache.jdo.jdoql.tree.Node

arrive, getChildren, getJavaClass, getObject, getParent, getTokenType, leave, setObject, setParent, walkNextChild

Method Detail

getTarget

public Expression getTarget()

Returns the target expression of this field access. The target expression can be an instance of ThisExpression or an instance of an arbitrary other Expression, e.g. FieldAccessExpression.

Returns:

the target expression

getFieldValue

public java.lang.Object getFieldValue(javax.jdo.PersistenceManager pm,
                                      java.lang.Object object)

Returns the value of the field corresponding with this field access expression for the argument object.

Parameters:

pm - the persistence manager of the query

object - the instance for which to return the field value

Returns:

the field value for object

Throws:

JDOQueryException - if access to the corresponding field of this expression is denied