com.solarmetric.rd.kodo.query.exp
Class OrderExpression

java.lang.Object
  |
  +--com.solarmetric.rd.kodo.query.exp.InMemoryExpression
        |
        +--com.solarmetric.rd.kodo.query.exp.OrderExpression

All Implemented Interfaces:

java.util.Comparator, Expression

public class OrderExpression

extends InMemoryExpression

implements java.util.Comparator

Wraps another expression and orders its results.

Constructor Summary

OrderExpression(com.solarmetric.rd.kodo.query.exp.InMemoryExpression exp, com.solarmetric.rd.kodo.query.exp.InMemoryValue val, boolean asc)
Constructor.

Method Summary

int	compare(java.lang.Object o1, java.lang.Object o2) Comparator that uses the result of eval'ing a Value to sort on.
protected boolean	eval(java.lang.Object candidate, java.lang.Object orig, com.solarmetric.rd.kodo.runtime.PersistenceManagerImpl pm, java.util.Map params) Evaluate the expression for the given context candidate and original candidate.
void	order(java.util.List matches, com.solarmetric.rd.kodo.runtime.PersistenceManagerImpl pm, java.util.Map params) Order the given list of matches according to this expression.

Methods inherited from class com.solarmetric.rd.kodo.query.exp.InMemoryExpression

evaluate

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Comparator

equals

Constructor Detail

OrderExpression

public OrderExpression(com.solarmetric.rd.kodo.query.exp.InMemoryExpression exp,
                       com.solarmetric.rd.kodo.query.exp.InMemoryValue val,
                       boolean asc)

Constructor. Supply delegate expression, the value to sort on, and the sort direction.

Method Detail

eval

protected boolean eval(java.lang.Object candidate,
                       java.lang.Object orig,
                       com.solarmetric.rd.kodo.runtime.PersistenceManagerImpl pm,
                       java.util.Map params)

Description copied from class: InMemoryExpression

Evaluate the expression for the given context candidate and original candidate.

Overrides:

eval in class InMemoryExpression

order

public void order(java.util.List matches,
                  com.solarmetric.rd.kodo.runtime.PersistenceManagerImpl pm,
                  java.util.Map params)

Description copied from class: InMemoryExpression

Order the given list of matches according to this expression.

Overrides:

order in class InMemoryExpression

compare

public int compare(java.lang.Object o1,
                   java.lang.Object o2)

Comparator that uses the result of eval'ing a Value to sort on. Null values are placed last if sorting in ascending order, first if descending.

Specified by:

compare in interface java.util.Comparator