Re: [rules-users] question about updating main memory

What I'm missing is an import statement in your drl file (import tests.Test.ClassP;). Everything else looks correct and should give the expected results (ResultSize = 5). Cheers, Jarek Senlin Liang wrote: > > Hi all, > > I am trying to insert some object, querying them and the retract them. > My question, when I query the inserted objects using defined "query", > it return 0 objects. But when I iterate over all objects in WM, the > objects are returned. > > Any information is appreciated! > > Files: > ===================test.drl==================== > package tests; > query "selectQuery" > p : ClassP() > end > ==================end of test.drl================ > > ==================Test.java==================== > package tests; > > import java.io.*; > import java.io.InputStreamReader; > import org.drools.RuleBase; > import org.drools.RuleBaseFactory; > import org.drools.StatefulSession; > import org.drools.compiler.PackageBuilder; > import org.drools.QueryResult; > import org.drools.QueryResults; > import org.drools.FactHandle; > import java.util.Iterator; > > public class Test { > public static void main (String args[]) { > try { > Reader source = new > InputStreamReader(Test.class.getResourceAsStream("../test.drl")); > final PackageBuilder builder = new PackageBuilder(); > builder.addPackageFromDrl(source); > if (builder.hasErrors()) { > System.out.println(builder.getErrors().toString()); > System.exit(0); > } > final RuleBase ruleBase = RuleBaseFactory.newRuleBase(); > ruleBase.addPackage(builder.getPackage()); > final StatefulSession session = ruleBase.newStatefulSession(); > > System.out.println("Inserting objects ..."); > for (int i = 0; i < 5; i ++) { > session.insert(new ClassP(1, i)); > } > > System.out.println("Querying objects ..."); > QueryResults results = session.getQueryResults("selectQuery"); > System.out.println("ResultSize = " + results.size()); > > /*************************************************************************************** > Here, it reports results.size() is 0, and there should be > 5 objects in WM right now. It is > the place I got the question. > > I have no idea whether I am using the "query" correctly. > Anything wrong? > > ***************************************************************************************/ > for (Iterator it = results.iterator(); it.hasNext(); ) { > final QueryResult result = (QueryResult) it.next(); > ClassP p = (ClassP) result.get("p"); > System.out.println("p(" + p.getFirst() + ", " + > p.getSecond()+")"); > } > > System.out.println("Deleting ..."); > for (Iterator it = session.iterateFactHandles(); it.hasNext(); > ) { > FactHandle factHandle = (FactHandle) it.next(); > ClassP p = (ClassP) session.getObject(factHandle); > System.out.println("p(" + p.getFirst() + ", " + > p.getSecond()+")"); > session.retract(factHandle); > } > > /*************************************************************************************** > Here, it prints out: it is deleting p(1, 1), ... p(1, 5). > It verifies that there are the 5 objects inserted. > > ***************************************************************************************/ > > session.dispose(); > } catch (Exception e) { > System.out.println(e); > System.exit(0); > } > } > > public static class ClassP { > private int first; > private int second; > public ClassP() {} > public ClassP(int firstIn, int secondIn) { > this.first = firstIn; > this.second = secondIn; > } > public int getFirst() { > return this.first; > } > public int getSecond() { > return this.second; > } > } > } > ========================end of Test.java===================== > > Thanks a lot, > _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users