il.ac.bgu.cs.bp.bpjs.model.eventsets.JsEventSet Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of BPjs Show documentation

Provides runtime and analysis for behavioral programs written in JavaScript. It can run stand-alone (from the commmandline) or be embedded in larger JVM-based systems.

The newest version!

package il.ac.bgu.cs.bp.bpjs.model.eventsets;

import il.ac.bgu.cs.bp.bpjs.model.BEvent;
import il.ac.bgu.cs.bp.bpjs.exceptions.BPjsRuntimeException;
import org.mozilla.javascript.Context;
import org.mozilla.javascript.EcmaError;
import org.mozilla.javascript.EvaluatorException;
import org.mozilla.javascript.Function;
import org.mozilla.javascript.NativeFunction;

/**
 * An event set whose predicate is a JavaScript function.
 *
 * @author michael
 */
public class JsEventSet implements EventSet, java.io.Serializable {

    private final Function predicate;
    private final String name;
    private final String encodedSource;

    public JsEventSet(String aName, Function aPredicate) {
        name = aName;
        predicate = aPredicate;
        if ( aPredicate instanceof NativeFunction ) {
            encodedSource = ((NativeFunction)aPredicate).getEncodedSource();
        } else {
            encodedSource = null;
        }
    }

    @Override
    public boolean contains(BEvent event) {
        try {
            Object result = predicate.call(Context.getCurrentContext(), predicate, predicate.getParentScope(),
                    new Object[]{Context.javaToJS(event, predicate.getParentScope())});

            Boolean res = (Boolean) Context.jsToJava(result, Boolean.class);
            if ( res == null ) {
                throw new BPjsRuntimeException("EventSet " + name + ": JS Predicate returned null, not a boolean value. " + predicate.toString());
            }
            return res;
        } catch (EvaluatorException ee) {
            throw new BPjsRuntimeException("EventSet " + name + ": JS Predicate did not return a boolean value.", ee);
        } catch (EcmaError ee) {
            throw new BPjsRuntimeException("Error evaluating JS Predicate " + name + ": " + ee.getMessage(), ee);
        }
    }

    public Function getPredicate() {
        return predicate;
    }

    public String getName() {
        return name;
    }

    @Override
    public String toString() {
        return "[JsEventSet: " + getName() +"]";
    }
    
    @Override
    public boolean equals( Object other ) {
        if ( other == null ) return false;
        if ( other == this ) return true;
        
        if ( other instanceof JsEventSet ) {
            JsEventSet otherES = (JsEventSet) other;
            if ( !name.equals(otherES.name) ) {
                return false;
            } else if ( encodedSource != null ) {
                return encodedSource.equals(otherES.encodedSource);
            } else {
                return predicate.equals(((JsEventSet) other).predicate);
            }
                
        } else {
            return false;
        }
    }
    
    @Override
    public int hashCode() {
        return (encodedSource!=null) ? encodedSource.hashCode() : predicate.hashCode();
    }
}