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1 package za.co.csir.icomtek.workflow.handlers;
2
3 import java.util.HashMap  ;
4 import java.util.Vector ;
5 import java.util.Iterator ;
6 import java.util.Enumeration ;
7 import java.util.ArrayList ;
8 import java.util.StringTokenizer ;
9
10 import org.apache.commons.beanutils.ConvertUtils;
11 import org.apache.commons.beanutils.MethodUtils;
12 import org.apache.commons.beanutils.PropertyUtils;
13
14 import za.co.csir.icomtek.workflow.factories.ModuleInvokerFactory;
15 import za.co.csir.icomtek.workflow.interfaces.WorkflowContext;
16 import za.co.csir.icomtek.workflow.model.*;
17
18
21 public abstract class BaseHandler {
22
23 private static HashMap cachedActionObjects = new HashMap ();
24 private static final String INVOKE = "invoke";
25
26 public static Object [] populateParameterValues (Vector params,
27 WorkflowContext ctx,
28 ArrayList requestAttributes)
29 throws Exception
30 {
31 Object [] retVals = new Object [params.size()];
32 int i = 0;
33 for (Iterator it = params.iterator(); it.hasNext(); i++) {
34 ParameterElement paramElement = (ParameterElement)it.next();
35 if (paramElement.getParameter() != null) {
36 Parameter param = paramElement.getParameter();
37 retVals[i] = getValFromParam(ctx, param, requestAttributes);
38 } else if (paramElement.getAction() != null ) {
39 Action action = paramElement.getAction();
40 retVals[i] = getValFromAction(ctx, action, requestAttributes);
41 } else if (paramElement.getProperty() != null ) {
42 Property prop = paramElement.getProperty();
43 retVals[i] = getValFromProperty(ctx, prop, requestAttributes);
44 }
45 }
46 return retVals;
47 }
48
49 private static Object getValFromProperty (WorkflowContext ctx,
50 Property prop,
51 ArrayList requestAttributes)
52 throws Exception
53 {
54 String propVal = prop.getProp();
55 System.err.println("<< resolving property: "+ propVal);
56 Object actionVal = getValFromAction(ctx, prop.getAction(),
57 requestAttributes);
58 StringTokenizer st = new StringTokenizer (propVal, ".");
60 while (st.hasMoreTokens()) {
61 actionVal = resolveProperty(st.nextToken(), actionVal);
62 }
63 if (prop.getName() != null) {
64 ctx.setRequestAttribute(prop.getName(), actionVal);
65 requestAttributes.add(prop.getName());
66 System.err.println("<< setting property: " + actionVal
67 + " with name: " + prop.getName());
68 }
69 return actionVal;
70 }
71
72 private static Object resolveProperty (String prop, Object obj)
73 throws Exception
74 {
75 System.err.println("<< resolving property: "+prop);
76 Object actionVal = null;
77 int idx2 = prop.indexOf("()");
78 if (idx2 > 0) {
79 actionVal = MethodUtils.invokeMethod(obj, prop.substring(0, idx2),
81 null);
82 } else {
83 actionVal = PropertyUtils.getProperty(obj, prop);
84 }
85 System.err.println("<< returing property val: "+actionVal);
86 return actionVal;
87 }
88
89 private static Object getValFromParam (WorkflowContext ctx,
90 Parameter param,
91 ArrayList requestAttributes)
92 throws Exception
93 {
94 Object retVal = null;
95 System.err.println("<<resolving param name: "+param.getParameterTypeChoice().getName());
96 System.err.println("<<resolving param type: "+param.getParameterTypeChoice().getType());
97 System.err.println("<<resolving param val: "+param.getValue());
98 if (param.getParameterTypeChoice().getName() != null) {
99 ctx.setRequestAttribute(param.getParameterTypeChoice().getName(),
100 param.getValue());
101 requestAttributes.add(param.getParameterTypeChoice().getName());
102 retVal = param.getValue();
103 } else {
104 retVal = ConvertUtils.convert(param.getValue(),
105 Class.forName(param.getParameterTypeChoice().getType()));
106 }
107 return retVal;
108 }
109
110 private static Object getValFromAction (WorkflowContext ctx,
111 Action action,
112 ArrayList requestAttributes)
113 throws Exception
114 {
115 Object [] params = new Object [action.getParameterElementCount()];
116 int i = 0;
117 for (Enumeration e = action.enumerateParameterElement();
118 e.hasMoreElements() ; i++) {
119 ParameterElement paramEle = (ParameterElement)e.nextElement();
120 if (paramEle.getParameter() != null) {
121 params[i] = getValFromParam(ctx, paramEle.getParameter(),
122 requestAttributes);
123 } else if (paramEle.getAction() != null) {
124 params[i] = getValFromAction(ctx, paramEle.getAction(),
125 requestAttributes);
126 }
127 }
128 Object retVal = executeAction(ctx, action, null);
129 if (action.getName() != null) {
130 System.err.println("<< setting: "+retVal+" in request as: |"+action.getName()+"|");
131 ctx.setRequestAttribute(action.getName(), retVal);
132 requestAttributes.add(action.getName());
133 }
134 return retVal;
135 }
136
137 public static Object executeAction (WorkflowContext ctx,
138 Action action,
139 Object [] params) throws Exception
140 {
141 String className = action.getClazz();
142 String methodCall = action.getMethod();
143 Object retVal = null;
144 if (className.indexOf(".") > 0) {
145 Object actionObj = cachedActionObjects.get(className);
147 if (actionObj == null) {
148 actionObj = Class.forName(className).newInstance();
150 cachedActionObjects.put(className, actionObj);
151 }
152 retVal = MethodUtils.invokeMethod(actionObj, methodCall, params);
153 System.err.println("<< invoked class: "+className
154 +" with method: "+methodCall);
155 System.err.println("<< got back value: "+retVal);
156 } else {
157 try {
159 ctx.beginWorkflowAction();
160 retVal = ModuleInvokerFactory.instance()
161 .getWorkflowModuleInvoker()
162 .invokeOpOnModule(className, methodCall, ctx);
163 System.err.println("<< invoked module: "+className
164 +" with method: "+methodCall);
165 System.err.println("<< got back value: "+retVal);
166 } finally {
167 ctx.endWorkflowAction();
168 }
169 }
170 return retVal;
171 }
172
173 public static void clearRequestAttributes (WorkflowContext ctx,
174 ArrayList requestAttributes) {
175 for (Iterator it = requestAttributes.iterator(); it.hasNext(); ) {
176 String attrName = (String )it.next();
177 ctx.removeRequestAttribute(attrName);
178 }
179 }
180 }
181 |
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