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1 package org.jicengine.element.impl;
2
3 import org.jicengine.element.*;
4 import org.jicengine.operation.*;
5 import java.util.*;
6
17 public class SwitchCompiler extends ElementCompiler {
18
19 public SwitchCompiler(String  name, Location location, String [] parameters) throws ElementException
20 {
21 super(name, location);
22
23 getElement().setConstructor(new Chooser(parameters[0]));
24 }
25
26
32 protected ActionElement handleLooseVariableElement(final VariableElement child) throws ElementException
33 {
34
37 ((Chooser)getElement().getConstructor()).addCase(child);
39
40 return new ActionElement(){
42 public void execute(Context context, Object parentInstance)
43 {
44 }
45 public String getName()
46 {
47 return child.getName();
48 }
49 public Location getLocation()
50 {
51 return child.getLocation();
52 }
53 public boolean isExecuted(Context outerContext, Object parentInstance)
54 {
55 return false;
56 }
57 };
58 }
59
60 public class Chooser implements Operation {
61 private String variable;
62 private List caseNames = new ArrayList();
63 private List cases = new ArrayList();
64 private VariableElement defaultCase;
65
66 public Chooser(String variable)
67 {
68 this.variable = variable;
69 }
70
71 public void addCase(VariableElement child)
72 {
73 if( child.getName().equals("default") ){
74 this.defaultCase = child;
75 }
76 else {
77 this.cases.add(child);
78 this.caseNames.add(child.getName());
79 }
80 }
81
82 public boolean needsParameters()
83 {
84 return true;
85 }
86
87 public boolean needsParameter(String name)
88 {
89 return name.equals(this.variable);
90 }
91
92 public Object execute(Context context) throws OperationException
93 {
94 Object variableValue = new VariableValueOperation(this.variable).execute(context);
95
96 String stringValue = String.valueOf(variableValue);
97
98 VariableElement selected = null;
99 for (int i = 0; i < this.caseNames.size(); i++) {
100 String candidate = this.caseNames.get(i).toString();
101 if( candidate.equals(stringValue) ){
102 selected = (VariableElement) this.cases.get(i);
104 break;
105 }
106 }
107
108 if( selected == null ){
109 if( this.defaultCase != null ){
110 selected = this.defaultCase;
111 }
112 else {
113 throw new OperationException("Case '" + stringValue + "' not found among " + this.caseNames);
114 }
115 }
116 Context elementContext = ((LocalContext)context).getParent();
117 try {
118 Object result = selected.getValue(elementContext, null);
119 return result;
120 } catch (ElementException e){
121 throw new OperationException(e.getMessage(), e);
122 }
123 }
124 }
125
126 }
127 |
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