org.apache.openjpa.kernel.exps
Class Coalesce

java.lang.Object
  org.apache.openjpa.kernel.exps.Val
      org.apache.openjpa.kernel.exps.Coalesce

All Implemented Interfaces:

Serializable, Value

public class Coalesce
extends Val

An in-memory representation of a coalesce expression

Author:

Catalina Wei

See Also:

Serialized Form

Method Summary

void	acceptVisit(ExpressionVisitor visitor) Accept a visit from a tree visitor.
protected boolean	compare(Object o1, Object o2) Compare the two values.
protected Object	eval(Object candidate, Object orig, StoreContext ctx, Object[] params) Return this value for the given candidate.
protected Object	eval(Object candidate, StoreContext ctx, Object[] params)
Class	getType() Return the expected type for this value, or Object if the type is unknown.
Val[]	getVal()
void	setImplicitType(Class type) Set the implicit type of the value, based on how it is used in the filter.

Methods inherited from class org.apache.openjpa.kernel.exps.Val

eval, evaluate, evaluate, getAlias, getMetaData, getName, getPath, getSelectAs, isAggregate, isVariable, isXPath, setAlias, setMetaData

Methods inherited from class java.lang.Object

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

Method Detail

eval

protected Object eval(Object candidate,
                      Object orig,
                      StoreContext ctx,
                      Object[] params)

Description copied from class: Val

Return this value for the given candidate.

Specified by:

eval in class Val

eval

protected Object eval(Object candidate,
                      StoreContext ctx,
                      Object[] params)

compare

protected boolean compare(Object o1,
                          Object o2)

Compare the two values.

getVal

public Val[] getVal()

getType

public Class getType()

Description copied from interface: Value

Return the expected type for this value, or Object if the type is unknown.

setImplicitType

public void setImplicitType(Class type)

Description copied from interface: Value

Set the implicit type of the value, based on how it is used in the filter. This method is only called on values who return Object from Value.getType().

acceptVisit

public void acceptVisit(ExpressionVisitor visitor)

Description copied from interface: Value

Accept a visit from a tree visitor.

Specified by:

acceptVisit in interface Value

Overrides:

acceptVisit in class Val