package org.drools.workflow.instance.node;
/*
* Copyright 2005 JBoss Inc
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import java.util.HashMap;
import java.util.Map;
import org.drools.definition.process.Connection;
import org.drools.process.core.context.variable.VariableScope;
import org.drools.process.instance.context.variable.VariableScopeInstance;
import org.drools.runtime.process.NodeInstance;
import org.drools.workflow.core.node.Join;
import org.drools.workflow.instance.impl.NodeInstanceImpl;
/**
* Runtime counterpart of a join node.
*
* @author <a href="mailto:kris_verlaenen@hotmail.com">Kris Verlaenen</a>
*/
public class JoinInstance extends NodeInstanceImpl {
private static final long serialVersionUID = 400L;
private Map<Long, Integer> triggers = new HashMap<Long, Integer>();
protected Join getJoin() {
return (Join) getNode();
}
public void internalTrigger(final NodeInstance from, String type) {
if (!org.drools.workflow.core.Node.CONNECTION_DEFAULT_TYPE.equals(type)) {
throw new IllegalArgumentException(
"An ActionNode only accepts default incoming connections!");
}
final Join join = getJoin();
switch ( join.getType() ) {
case Join.TYPE_XOR :
triggerCompleted();
break;
case Join.TYPE_AND :
Integer count = (Integer) this.triggers.get( from.getNodeId() );
if ( count == null ) {
this.triggers.put( from.getNodeId(),
1 );
} else {
this.triggers.put( from.getNodeId(),
count.intValue() + 1 );
}
if (checkAllActivated()) {
decreaseAllTriggers();
triggerCompleted();
}
break;
case Join.TYPE_DISCRIMINATOR :
boolean triggerCompleted = triggers.isEmpty();
triggers.put( from.getNodeId(), new Integer( 1 ) );
if (checkAllActivated()) {
resetAllTriggers();
}
if (triggerCompleted) {
triggerCompleted();
}
break;
case Join.TYPE_N_OF_M :
count = (Integer) this.triggers.get( from.getNodeId() );
if ( count == null ) {
this.triggers.put( from.getNodeId(),
1 );
} else {
this.triggers.put( from.getNodeId(),
count.intValue() + 1 );
}
int counter = 0;
for (final Connection connection: getJoin().getDefaultIncomingConnections()) {
if ( this.triggers.get( connection.getFrom().getId() ) != null ) {
counter++;
}
}
String n = join.getN();
Integer number = null;
if (n.startsWith("#{") && n.endsWith("}")) {
n = n.substring(2, n.length() - 1);
VariableScopeInstance variableScopeInstance = (VariableScopeInstance)
resolveContextInstance(VariableScope.VARIABLE_SCOPE, n);
if (variableScopeInstance == null) {
throw new IllegalArgumentException(
"Could not find variable " + n + " when executing join.");
}
Object value = variableScopeInstance.getVariable(n);
if (value instanceof Number) {
number = ((Number) value).intValue();
} else {
throw new IllegalArgumentException(
"Variable " + n + " did not return a number when executing join: " + value);
}
} else {
number = new Integer(n);
}
if (counter >= number) {
resetAllTriggers();
triggerCompleted();
}
break;
default :
throw new IllegalArgumentException( "Illegal join type " + join.getType() );
}
}
private boolean checkAllActivated() {
// check whether all parent nodes have been triggered
for (final Connection connection: getJoin().getDefaultIncomingConnections()) {
if ( this.triggers.get( connection.getFrom().getId() ) == null ) {
return false;
}
}
return true;
}
private void decreaseAllTriggers() {
// decrease trigger count for all incoming connections
for (final Connection connection: getJoin().getDefaultIncomingConnections()) {
final Integer count = (Integer) this.triggers.get( connection.getFrom().getId() );
if ( count.intValue() == 1 ) {
this.triggers.remove( connection.getFrom().getId() );
} else {
this.triggers.put( connection.getFrom().getId(),
count.intValue() - 1 );
}
}
}
private void resetAllTriggers() {
triggers.clear();
}
public void triggerCompleted() {
// join nodes are only removed from the container when they contain no more state
triggerCompleted(org.drools.workflow.core.Node.CONNECTION_DEFAULT_TYPE, triggers.isEmpty());
}
public Map<Long, Integer> getTriggers() {
return triggers;
}
public void internalSetTriggers(Map<Long, Integer> triggers) {
this.triggers = triggers;
}
}