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1 package org.jbpm.graph.action;
2
3 import java.util.HashMap  ;
4 import java.util.HashSet ;
5 import java.util.Iterator ;
6 import java.util.Map ;
7 import java.util.Set ;
8
9 import bsh.EvalError;
10 import bsh.Interpreter;
11
12 import org.apache.commons.logging.Log;
13 import org.apache.commons.logging.LogFactory;
14 import org.dom4j.Element;
15 import org.jbpm.context.def.VariableAccess;
16 import org.jbpm.context.exe.ContextInstance;
17 import org.jbpm.graph.def.Action;
18 import org.jbpm.graph.exe.ExecutionContext;
19 import org.jbpm.graph.exe.Token;
20 import org.jbpm.jpdl.xml.JpdlXmlReader;
21 import org.jbpm.jpdl.xml.Parsable;
22
23 public class Script extends Action implements Parsable {
24
25 private static final long serialVersionUID = 1L;
26
27 protected String expression = null;
28 protected Set variableAccesses = null;
29
30 public void read(Element scriptElement, JpdlXmlReader jpdlReader) {
31 if (scriptElement.isTextOnly()) {
32 expression = scriptElement.getTextTrim();
33 } else {
34 this.variableAccesses = new HashSet (jpdlReader.readVariableAccesses(scriptElement));
35 expression = scriptElement.element("expression").getTextTrim();
36 }
37 }
38
39 public void execute(ExecutionContext executionContext) {
40 Map outputMap = eval(executionContext);
41 setVariables(outputMap, executionContext);
42 }
43
44 public Map eval(Token token) {
45 return eval(new ExecutionContext(token));
46 }
47
48 public Map eval(ExecutionContext executionContext) {
49 Map inputMap = createInputMap(executionContext);
50 Set outputNames = getOutputNames();
51 return eval(inputMap, outputNames);
52 }
53
54 public Map createInputMap(ExecutionContext executionContext) {
55 Map inputMap = new HashMap ();
56 inputMap.put( "executionContext", executionContext );
57 inputMap.put( "token", executionContext.getToken() );
58 inputMap.put( "node", executionContext.getNode() );
59 inputMap.put( "task", executionContext.getTask() );
60 inputMap.put( "taskInstance", executionContext.getTaskInstance() );
61
62 ContextInstance contextInstance = executionContext.getContextInstance();
64 if (! hasReadableVariable()) {
65 Map variables = contextInstance.getVariables();
67 if ( variables != null ) {
68 Iterator iter = variables.entrySet().iterator();
69 while( iter.hasNext() ) {
70 Map.Entry entry = (Map.Entry ) iter.next();
71 String variableName = (String ) entry.getKey();
72 Object variableValue = entry.getValue();
73 inputMap.put(variableName, variableValue);
74 }
75 }
76
77 } else {
78 Iterator iter = variableAccesses.iterator();
80 while (iter.hasNext()) {
81 VariableAccess variableAccess = (VariableAccess) iter.next();
82 if (variableAccess.isReadable()) {
83 String variableName = variableAccess.getVariableName();
84 String mappedName = variableAccess.getMappedName();
85 Object variableValue = contextInstance.getVariable(variableName);
86 inputMap.put(mappedName, variableValue);
87 }
88 }
89 }
90
91 return inputMap;
92 }
93
94 public Map eval(Map inputMap, Set outputNames) {
95 Map outputMap = new HashMap ();
96
97 try {
98 log.debug("script input: "+inputMap);
99 Interpreter interpreter = new Interpreter();
100 Iterator iter = inputMap.keySet().iterator();
101 while (iter.hasNext()) {
102 String inputName = (String ) iter.next();
103 Object inputValue = inputMap.get(inputName);
104 if (inputValue!=null) {
105 interpreter.set(inputName, inputValue);
106 }
107 }
108 interpreter.eval(expression);
109 iter = outputNames.iterator();
110 while (iter.hasNext()) {
111 String outputName = (String ) iter.next();
112 Object outputValue = interpreter.get(outputName);
113 outputMap.put(outputName, outputValue);
114 }
115 log.debug("script output: "+outputMap);
116 } catch (EvalError e) {
117 throw new RuntimeException ("can't evaluate beanshell script '"+expression+"'", e);
118 }
119
120 return outputMap;
121 }
122
123 public void addVariableAccess(VariableAccess variableAccess) {
124 if (variableAccesses==null) variableAccesses = new HashSet ();
125 variableAccesses.add(variableAccess);
126 }
127
128 Set getOutputNames() {
129 Set outputNames = new HashSet ();
130 if (variableAccesses!=null) {
131 Iterator iter = variableAccesses.iterator();
132 while (iter.hasNext()) {
133 VariableAccess variableAccess = (VariableAccess) iter.next();
134 if (variableAccess.isWritable()) {
135 outputNames.add(variableAccess.getMappedName());
136 }
137 }
138 }
139 return outputNames;
140 }
141
142 boolean hasReadableVariable() {
143 if (variableAccesses==null) return false;
144 Iterator iter = variableAccesses.iterator();
145 while (iter.hasNext()) {
146 VariableAccess variableAccess = (VariableAccess) iter.next();
147 if (variableAccess.isReadable()) {
148 return true;
149 }
150 }
151 return false;
152 }
153
154 void setVariables(Map outputMap, ExecutionContext executionContext) {
155 if ( (outputMap!=null)
156 && (!outputMap.isEmpty())
157 && (executionContext!=null)
158 ) {
159 Map variableNames = getVariableNames();
160 ContextInstance contextInstance = executionContext.getContextInstance();
161 Token token = executionContext.getToken();
162
163 Iterator iter = outputMap.keySet().iterator();
164 while (iter.hasNext()) {
165 String mappedName = (String ) iter.next();
166 String variableName = (String ) variableNames.get(mappedName);
167 contextInstance.setVariable(variableName, outputMap.get(mappedName), token);
168 }
169 }
170 }
171
172 Map getVariableNames() {
173 Map variableNames = new HashMap ();
174 Iterator iter = variableAccesses.iterator();
175 while (iter.hasNext()) {
176 VariableAccess variableAccess = (VariableAccess) iter.next();
177 if (variableAccess.isWritable()) {
178 variableNames.put(variableAccess.getMappedName(), variableAccess.getVariableName());
179 }
180 }
181 return variableNames;
182 }
183
184 public String getExpression() {
185 return expression;
186 }
187 public void setExpression(String expression) {
188 this.expression = expression;
189 }
190 public Set getVariableAccesses() {
191 return variableAccesses;
192 }
193 public void setVariableAccesses(Set variableAccesses) {
194 this.variableAccesses = variableAccesses;
195 }
196
197 private static final Log log = LogFactory.getLog(Script.class);
198 }
199 |
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