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1
52
53 package freemarker.template;
54
55 import java.io.Serializable  ;
56 import java.util.*;
57
58
75 public class SimpleCollection extends WrappingTemplateModel
76 implements TemplateCollectionModel, Serializable {
77
78 private boolean iteratorDirty;
79 private Iterator iterator;
80 private Collection collection;
81
82 public SimpleCollection(Iterator iterator) {
83 this.iterator = iterator;
84 }
85
86 public SimpleCollection(Collection collection) {
87 this.collection = collection;
88 }
89
90 public SimpleCollection(Iterator iterator, ObjectWrapper wrapper) {
91 super(wrapper);
92 this.iterator = iterator;
93 }
94
95 public SimpleCollection(Collection collection, ObjectWrapper wrapper) {
96 super(wrapper);
97 this.collection = collection;
98 }
99
100
109 public TemplateModelIterator iterator() {
110 if (iterator != null) {
111 return new SimpleTemplateModelIterator(iterator, true);
112 } else {
113 synchronized (collection) {
114 return new SimpleTemplateModelIterator(collection.iterator(), false);
115 }
116 }
117 }
118
119
125 private class SimpleTemplateModelIterator implements TemplateModelIterator {
126
127 private Iterator iterator;
128 private boolean iteratorShared;
129
130 SimpleTemplateModelIterator(Iterator iterator, boolean iteratorShared) {
131 this.iterator = iterator;
132 this.iteratorShared = iteratorShared;
133 }
134
135 public TemplateModel next() throws TemplateModelException {
136 if (iteratorShared) makeIteratorDirty();
137
138 if (!iterator.hasNext()) {
139 throw new TemplateModelException("The collection has no more elements.");
140 }
141
142 Object value = iterator.next();
143 if (value instanceof TemplateModel) {
144 return (TemplateModel) value;
145 } else {
146 return wrap(value);
147 }
148 }
149
150 public boolean hasNext() throws TemplateModelException {
151
155 if (iteratorShared) makeIteratorDirty();
156 return iterator.hasNext();
157 }
158
159 private void makeIteratorDirty() throws TemplateModelException {
160 synchronized (SimpleCollection.this) {
161 if (iteratorDirty) {
162 throw new TemplateModelException(
163 "This collection variable wraps a java.util.Iterator, "
164 + "thus it can be <list>-ed or <foreach>-ed only once");
165 } else {
166 iteratorDirty = true;
167 iteratorShared = false;
168 }
169 }
170 }
171 }
172 }
173 |
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