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1
52
53 package freemarker.core;
54
55 import java.io.IOException  ;
56 import java.util.HashSet ;
57 import java.util.Set ;
58 import freemarker.template.*;
59
60
63 final class IteratorBlock extends TemplateElement {
64
65 private Expression listExpression;
66 private String indexName;
67 private boolean isForEach;
68
69
74 IteratorBlock(Expression listExpression,
75 String indexName,
76 TemplateElement nestedBlock,
77 boolean isForEach)
78 {
79 this.listExpression = listExpression;
80 this.indexName = indexName;
81 this.isForEach = isForEach;
82 this.nestedBlock = nestedBlock;
83 }
84
85 void accept(Environment env) throws TemplateException, IOException
86 {
87 TemplateModel baseModel = listExpression.getAsTemplateModel(env);
88 if (baseModel == null) {
89 if (env.isClassicCompatible()) {
90 return;
92 }
93 assertNonNull(baseModel, listExpression, env);
94 }
95 env.visit(new Context(baseModel));
96 }
97
98 public String getCanonicalForm() {
99 if (isForEach) {
100 StringBuffer buf = new StringBuffer ("<#foreach ");
101 buf.append(indexName);
102 buf.append(" in ");
103 buf.append(listExpression.getCanonicalForm());
104 buf.append(">");
105 if (nestedBlock != null) {
106 buf.append(nestedBlock.getCanonicalForm());
107 }
108 buf.append("</#foreach>");
109 return buf.toString();
110 }
111 else {
112 StringBuffer buf = new StringBuffer ("<#list ");
113 buf.append(listExpression.getCanonicalForm());
114 buf.append(" as ");
115 buf.append(indexName);
116 buf.append(">");
117 if (nestedBlock != null) {
118 buf.append(nestedBlock.getCanonicalForm());
119 }
120 buf.append("</#list>");
121 return buf.toString();
122 }
123 }
124
125 public String getDescription() {
126 if (isForEach) {
127 return "foreach " + indexName + " in " + listExpression;
128
129 }
130 else {
131 return "list " + listExpression + " as " + indexName;
132 }
133 }
134
135
138
139 class Context implements LocalContext {
140 private boolean hasNext;
141 private TemplateModel loopVar;
142 private int index;
143 private Set variableNames = null;
144 private TemplateModel list;
145
146 Context(TemplateModel list) {
147 this.list = list;
148 }
149
150
151 void runLoop(Environment env) throws TemplateException, IOException {
152 if (list instanceof TemplateCollectionModel) {
153 TemplateCollectionModel baseListModel = (TemplateCollectionModel)list;
154 TemplateModelIterator it = baseListModel.iterator();
155 hasNext = it.hasNext();
156 while (hasNext) {
157 loopVar = it.next();
158 hasNext = it.hasNext();
159 if (nestedBlock != null) {
160 env.visit(nestedBlock);
161 }
162 index++;
163 }
164 }
165 else if (list instanceof TemplateSequenceModel) {
166 TemplateSequenceModel tsm = (TemplateSequenceModel) list;
167 int size = tsm.size();
168 for (index =0; index <size; index++) {
169 loopVar = tsm.get(index);
170 hasNext = (size > index +1);
171 if (nestedBlock != null) {
172 env.visit(nestedBlock);
173 }
174 }
175 }
176 else if (env.isClassicCompatible()) {
177 loopVar = list;
178 if (nestedBlock != null) {
179 env.visit(nestedBlock);
180 }
181 }
182 else {
183 throw invalidTypeException(list, listExpression, env, "collection or sequence");
184 }
185 }
186
187 public TemplateModel getLocalVariable(String name) {
188 if (name.startsWith(indexName)) {
189 switch(name.length() - indexName.length()) {
190 case 0:
191 return loopVar;
192 case 6:
193 if(name.endsWith("_index")) {
194 return new SimpleNumber(index);
195 }
196 break;
197 case 9:
198 if(name.endsWith("_has_next")) {
199 return hasNext ? TemplateBooleanModel.TRUE : TemplateBooleanModel.FALSE;
200 }
201 break;
202 }
203 }
204 return null;
205 }
206
207 public Set getLocalVariableNames() {
208 if(variableNames == null) {
209 variableNames = new HashSet ();
210 variableNames.add(indexName);
211 variableNames.add(indexName + "_index");
212 variableNames.add(indexName + "_has_next");
213 }
214 return variableNames;
215 }
216 }
217 }
218 |
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