I guess I didn't look at it carefully, sorry. ^_^ You probably also want to make a change to the last line (return new Boolean(left && right);) in that block.

Xiping

Inactive hide details for David Wood/Watson/IBM@IBMUSDavid Wood/Watson/IBM@IBMUS


          David Wood/Watson/IBM@IBMUS

          05/29/2009 10:14 AM
          Please respond to
          imperius-dev@incubator.apache.org


To

imperius-dev@incubator.apache.org

cc

imperius-dev@incubator.apache.org

Subject

Re: svn commit: r779776 - in /incubator/imperius/trunk/imperius-splcore/src/main/java/org/apache/imperius/spl/parser/expressions/impl: LogicalAnd.java LogicalOr.java

The original code did this

boolean right = ((Boolean) _rhsExp.evaluate()).booleanValue();

Always!  My change makes it so that it only does it if the left-hand side
evaluates to true (this is for the && case).  what you suggest would work
as well.

David Wood
Policy Technologies Group
IBM TJ Watson Research Center
dawood@us.ibm.com
914-784-5123 (office), 914-396-6515 (mobile)




From:
Xiping Wang/Watson/IBM@IBMUS
To:
imperius-dev@incubator.apache.org
Date:
05/29/2009 09:12 AM
Subject:
Re: svn commit: r779776 - in
/incubator/imperius/trunk/imperius-splcore/src/main/java/org/apache/imperius/spl/parser/expressions/impl:
LogicalAnd.java LogicalOr.java



David,

I am not sure what the difference is between your changes and the original
code. I thought you wanted to optimize the code by simplifying evaluation
process as I described below. Am I missing something?

//for LogicalAnd
boolean left = ((Boolean) _lhsExp.evaluate()).booleanValue();
if (!left) return Boolean(false) //no further evaluation


//for LogicalOr
boolean left = ((Boolean) _lhsExp.evaluate()).booleanValue();
if (left) return Boolean(true) //no further evaluation

In addition, the left hand side or the right hand side can be a constant
expression, so a constant expression can always be eliminated when a
logical expression is created.

Xiping


dawood@apache.org


dawood@apache.org
05/28/2009 05:18 PM

Please respond to
imperius-dev@incubator.apache.org




To

imperius-commits@incubator.apache.org

cc


Subject

svn commit: r779776 - in
/incubator/imperius/trunk/imperius-splcore/src/main/java/org/apache/imperius/spl/parser/expressions/impl:
LogicalAnd.java LogicalOr.java





Author: dawood
Date: Thu May 28 21:18:43 2009
New Revision: 779776

URL:
http://svn.apache.org/viewvc?rev=779776&view=rev
Log:
implement short-circuited evaluation.

Modified:

incubator/imperius/trunk/imperius-splcore/src/main/java/org/apache/imperius/spl/parser/expressions/impl/LogicalAnd.java

incubator/imperius/trunk/imperius-splcore/src/main/java/org/apache/imperius/spl/parser/expressions/impl/LogicalOr.java

Modified:
incubator/imperius/trunk/imperius-splcore/src/main/java/org/apache/imperius/spl/parser/expressions/impl/LogicalAnd.java
URL:
http://svn.apache.org/viewvc/incubator/imperius/trunk/imperius-splcore/src/main/java/org/apache/imperius/spl/parser/expressions/impl/LogicalAnd.java?rev=779776&r1=779775&r2=779776&view=diff

==============================================================================
---
incubator/imperius/trunk/imperius-splcore/src/main/java/org/apache/imperius/spl/parser/expressions/impl/LogicalAnd.java
(original)
+++
incubator/imperius/trunk/imperius-splcore/src/main/java/org/apache/imperius/spl/parser/expressions/impl/LogicalAnd.java
Thu May 28 21:18:43 2009
@@ -76,7 +76,7 @@
       try
       {
           boolean left = ((Boolean) _lhsExp.evaluate()).booleanValue();
-            boolean right = ((Boolean)
_rhsExp.evaluate()).booleanValue();
+            boolean right = left && ((Boolean)
_rhsExp.evaluate()).booleanValue();

           logger.exiting(sourceClass,Thread.currentThread().getName()+"
"+ "evaluate");


Modified:
incubator/imperius/trunk/imperius-splcore/src/main/java/org/apache/imperius/spl/parser/expressions/impl/LogicalOr.java
URL:
http://svn.apache.org/viewvc/incubator/imperius/trunk/imperius-splcore/src/main/java/org/apache/imperius/spl/parser/expressions/impl/LogicalOr.java?rev=779776&r1=779775&r2=779776&view=diff

==============================================================================
---
incubator/imperius/trunk/imperius-splcore/src/main/java/org/apache/imperius/spl/parser/expressions/impl/LogicalOr.java
(original)
+++
incubator/imperius/trunk/imperius-splcore/src/main/java/org/apache/imperius/spl/parser/expressions/impl/LogicalOr.java
Thu May 28 21:18:43 2009
@@ -79,7 +79,7 @@
       {
          //System.out.println("Logical OR::LHS type: RHS type ::"+
lhsExp.getType() + ":" + rhsExp.getType());
           boolean left = ((Boolean) _lhsExp.evaluate()).booleanValue();
-            boolean right = ((Boolean)
_rhsExp.evaluate()).booleanValue();
+            boolean right = left || ((Boolean)
_rhsExp.evaluate()).booleanValue();
          //System.out.println("Logical OR::after Evaluation LHS: RHS
::"+ left + ":" + right);
           logger.exiting(sourceClass,Thread.currentThread().getName()+"
"+ "evaluate");