org.apache.openjpa.kernel.exps
Class MathVal

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

All Implemented Interfaces:

Serializable, Value

Direct Known Subclasses:

Add, Divide, Mod, Multiply, Subtract

abstract class MathVal
extends Val

Value produced by a mathematical operation on two values.

Author:

Abe White

Constructor Summary

MathVal(Val val1, Val val2)
Constructor.

Method Summary

void	acceptVisit(ExpressionVisitor visitor) Accept a visit from a tree visitor.
protected Object	eval(Object candidate, Object orig, StoreContext ctx, Object[] params) Return this value for the given candidate.
Class	getType() Return the expected type for this value, or Object if the type is unknown.
protected abstract Object	operate(Object o1, Class c1, Object o2, Class c2) Return the result of this mathematical operation on the two values.
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

Constructor Detail

MathVal

public MathVal(Val val1,
               Val val2)

Constructor. Provide the values to operate on.

Method Detail

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().

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

operate

protected abstract Object operate(Object o1,
                                  Class c1,
                                  Object o2,
                                  Class c2)

Return the result of this mathematical operation on the two values.

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