/* * JBoss, Home of Professional Open Source * Copyright 2005, JBoss Inc., and individual contributors as indicated * by the @authors tag. See the copyright.txt in the distribution for a * full listing of individual contributors. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package org.jbpm.graph.action; import java.util.Collections; import java.util.HashMap; import java.util.HashSet; import java.util.Iterator; import java.util.Map; import java.util.Set; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.dom4j.Element; import org.jbpm.context.def.VariableAccess; import org.jbpm.context.exe.ContextInstance; import org.jbpm.graph.def.Action; import org.jbpm.graph.def.DelegationException; import org.jbpm.graph.exe.ExecutionContext; import org.jbpm.graph.exe.Token; import org.jbpm.jpdl.xml.JpdlXmlReader; import bsh.EvalError; import bsh.Interpreter; import bsh.ParseException; import bsh.TargetError; public class Script extends Action { private static final long serialVersionUID = 1L; protected String expression; protected Set variableAccesses; public void read(Element scriptElement, JpdlXmlReader jpdlReader) { if (scriptElement.isTextOnly()) { expression = scriptElement.getTextTrim(); } else { variableAccesses = new HashSet(jpdlReader.readVariableAccesses(scriptElement)); expression = scriptElement.element("expression").getTextTrim(); } } public void execute(ExecutionContext executionContext) throws Exception { Map outputMap = eval(executionContext); setVariables(outputMap, executionContext); } public String toString() { return "Script(" + expression + ')'; } public Map eval(Token token) { return eval(new ExecutionContext(token)); } public Map eval(ExecutionContext executionContext) { Map inputMap = createInputMap(executionContext); Set outputNames = getOutputNames(); return eval(inputMap, outputNames); } public Map createInputMap(ExecutionContext executionContext) { Token token = executionContext.getToken(); Map inputMap = new HashMap(); inputMap.put("executionContext", executionContext); inputMap.put("token", token); inputMap.put("node", executionContext.getNode()); inputMap.put("task", executionContext.getTask()); inputMap.put("taskInstance", executionContext.getTaskInstance()); // if no readable variableInstances are specified, ContextInstance contextInstance = executionContext.getContextInstance(); if (!hasReadableVariable()) { // put all variables into the input map Map variables = contextInstance.getVariables(token); if (variables != null) { for (Iterator iter = variables.entrySet().iterator(); iter.hasNext();) { Map.Entry entry = (Map.Entry) iter.next(); String variableName = (String) entry.getKey(); Object variableValue = entry.getValue(); inputMap.put(variableName, variableValue); } } } else { // put only the specified variables into the input map for (Iterator iter = variableAccesses.iterator(); iter.hasNext();) { VariableAccess variableAccess = (VariableAccess) iter.next(); if (variableAccess.isReadable()) { String variableName = variableAccess.getVariableName(); String mappedName = variableAccess.getMappedName(); Object variableValue = contextInstance.getVariable(variableName, token); inputMap.put(mappedName, variableValue); } } } return inputMap; } public Map eval(Map inputMap, Set outputNames) { try { // set input variables boolean debug = log.isDebugEnabled(); if (debug) log.debug("script input: " + inputMap); Interpreter interpreter = new Interpreter(); for (Iterator iter = inputMap.entrySet().iterator(); iter.hasNext();) { Map.Entry entry = (Map.Entry) iter.next(); interpreter.set((String) entry.getKey(), entry.getValue()); } // evaluate script interpreter.eval(expression); // get output variables if (outputNames.isEmpty()) return Collections.EMPTY_MAP; Map outputMap = new HashMap(); for (Iterator iter = outputNames.iterator(); iter.hasNext();) { String outputName = (String) iter.next(); Object outputValue = interpreter.get(outputName); outputMap.put(outputName, outputValue); } if (debug) log.debug("script output: " + outputMap); return outputMap; } catch (ParseException e) { throw new DelegationException("failed to parse script", e); } catch (TargetError e) { throw new DelegationException("script threw exception", e.getTarget()); } catch (EvalError e) { throw new DelegationException("script evaluation halted", e); } } public void addVariableAccess(VariableAccess variableAccess) { if (variableAccesses == null) variableAccesses = new HashSet(); variableAccesses.add(variableAccess); } private Set getOutputNames() { if (variableAccesses == null || variableAccesses.isEmpty()) return Collections.EMPTY_SET; Set outputNames = new HashSet(); for (Iterator iter = variableAccesses.iterator(); iter.hasNext();) { VariableAccess variableAccess = (VariableAccess) iter.next(); if (variableAccess.isWritable()) outputNames.add(variableAccess.getMappedName()); } return outputNames; } private boolean hasReadableVariable() { if (variableAccesses != null) { for (Iterator iter = variableAccesses.iterator(); iter.hasNext();) { VariableAccess variableAccess = (VariableAccess) iter.next(); if (variableAccess.isReadable()) return true; } } return false; } private void setVariables(Map outputMap, ExecutionContext executionContext) { if (variableAccesses == null) return; ContextInstance contextInstance = executionContext.getContextInstance(); Token token = executionContext.getToken(); for (Iterator iter = variableAccesses.iterator(); iter.hasNext();) { VariableAccess variableAccess = (VariableAccess) iter.next(); if (variableAccess.isWritable()) { Object value = outputMap.get(variableAccess.getMappedName()); contextInstance.setVariable(variableAccess.getVariableName(), value, token); } } } public String getExpression() { return expression; } public void setExpression(String expression) { this.expression = expression; } public Set getVariableAccesses() { return variableAccesses; } public void setVariableAccesses(Set variableAccesses) { this.variableAccesses = variableAccesses; } private static final Log log = LogFactory.getLog(Script.class); }