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1
14
15 package com.sun.facelets.tag.jstl.core;
16
17 import java.io.IOException  ;
18 import java.lang.reflect.Array ;
19 import java.util.Collection ;
20 import java.util.Iterator ;
21 import java.util.Map ;
22
23 import javax.el.ELException;
24 import javax.el.ValueExpression;
25 import javax.el.VariableMapper;
26 import javax.faces.FacesException;
27 import javax.faces.component.UIComponent;
28
29 import com.sun.facelets.FaceletContext;
30 import com.sun.facelets.FaceletException;
31 import com.sun.facelets.tag.TagAttribute;
32 import com.sun.facelets.tag.TagAttributeException;
33 import com.sun.facelets.tag.TagConfig;
34 import com.sun.facelets.tag.TagHandler;
35
36
41 public final class ForEachHandler extends TagHandler {
42
43 private static class ArrayIterator implements Iterator {
44
45 protected final Object array;
46
47 protected int i;
48
49 protected final int len;
50
51 public ArrayIterator(Object src) {
52 this.i = 0;
53 this.array = src;
54 this.len = Array.getLength(src);
55 }
56
57 public boolean hasNext() {
58 return this.i < this.len;
59 }
60
61 public Object next() {
62 return Array.get(this.array, this.i++);
63 }
64
65 public void remove() {
66 throw new UnsupportedOperationException ();
67 }
68 }
69
70 private final TagAttribute begin;
71
72 private final TagAttribute end;
73
74 private final TagAttribute items;
75
76 private final TagAttribute step;
77
78 private final TagAttribute tranzient;
79
80 private final TagAttribute var;
81
82 private final TagAttribute varStatus;
83
84
87 public ForEachHandler(TagConfig config) {
88 super(config);
89 this.items = this.getAttribute("items");
90 this.var = this.getAttribute("var");
91 this.begin = this.getAttribute("begin");
92 this.end = this.getAttribute("end");
93 this.step = this.getAttribute("step");
94 this.varStatus = this.getAttribute("varStatus");
95 this.tranzient = this.getAttribute("transient");
96
97 if (this.items == null && this.begin != null && this.end == null) {
98 throw new TagAttributeException(
99 this.tag,
100 this.begin,
101 "If the 'items' attribute is not specified, but the 'begin' attribute is, then the 'end' attribute is required");
102 }
103 }
104
105 public void apply(FaceletContext ctx, UIComponent parent)
106 throws IOException , FacesException, FaceletException, ELException {
107
108 int s = this.getBegin(ctx);
109 int e = this.getEnd(ctx);
110 int m = this.getStep(ctx);
111 Integer sO = this.begin != null ? new Integer (s) : null;
112 Integer eO = this.end != null ? new Integer (e) : null;
113 Integer mO = this.step != null ? new Integer (m) : null;
114
115 boolean t = this.getTransient(ctx);
116 Object src = null;
117 ValueExpression srcVE = null;
118 if (this.items != null) {
119 srcVE = this.items.getValueExpression(ctx, Object .class);
120 src = srcVE.getValue(ctx);
121 } else {
122 byte[] b = new byte[e + 1];
123 for (int i = 0; i < b.length; i++) {
124 b[i] = (byte) i;
125 }
126 src = b;
127 }
128 if (src != null) {
129 Iterator itr = this.toIterator(src);
130 if (itr != null) {
131 int i = 0;
132
133 while (i < s && itr.hasNext()) {
135 itr.next();
136 i++;
137 }
138
139 String v = this.getVarName(ctx);
140 String vs = this.getVarStatusName(ctx);
141 VariableMapper vars = ctx.getVariableMapper();
142 ValueExpression ve = null;
143 ValueExpression vO = this.capture(v, vars);
144 ValueExpression vsO = this.capture(vs, vars);
145 int mi = 0;
146 Object value = null;
147 try {
148 boolean first = true;
149 while (i <= e && itr.hasNext()) {
150 value = itr.next();
151
152 if (v != null) {
154 if (t || srcVE == null) {
155 ctx.setAttribute(v, value);
156 } else {
157 ve = this.getVarExpr(srcVE, src, value, i);
158 vars.setVariable(v, ve);
159 }
160 }
161
162 if (vs != null) {
164 IterationStatus itrS = new IterationStatus(first, !itr.hasNext(),i, sO, eO, mO);
165 if (t || srcVE == null) {
166 ctx.setAttribute(vs, itrS);
167 } else {
168 ve = new IterationStatusExpression(itrS);
169 vars.setVariable(vs, ve);
170 }
171 }
172
173 this.nextHandler.apply(ctx, parent);
175
176 mi = 1;
178 while (mi < m && itr.hasNext()) {
179 itr.next();
180 mi++;
181 i++;
182 }
183 i++;
184
185 first = false;
186 }
187 } finally {
188 if (v != null) {
189 vars.setVariable(v, vO);
190 }
191 if (vs != null) {
192 vars.setVariable(vs, vsO);
193 }
194 }
195 }
196 }
197 }
198
199 private final ValueExpression capture(String name, VariableMapper vars) {
200 if (name != null) {
201 return vars.setVariable(name, null);
202 }
203 return null;
204 }
205
206 private final int getBegin(FaceletContext ctx) {
207 if (this.begin != null) {
208 return this.begin.getInt(ctx);
209 }
210 return 0;
211 }
212
213 private final int getEnd(FaceletContext ctx) {
214 if (this.end != null) {
215 return this.end.getInt(ctx);
216 }
217 return Integer.MAX_VALUE;
218 }
219
220 private final int getStep(FaceletContext ctx) {
221 if (this.step != null) {
222 return this.step.getInt(ctx);
223 }
224 return 1;
225 }
226
227 private final boolean getTransient(FaceletContext ctx) {
228 if (this.tranzient != null) {
229 return this.tranzient.getBoolean(ctx);
230 }
231 return false;
232 }
233
234 private final ValueExpression getVarExpr(ValueExpression ve, Object src,
235 Object value, int i) {
236 if (src instanceof Collection || src.getClass().isArray()) {
237 return new IndexedValueExpression(ve, i);
238 } else if (src instanceof Map && value instanceof Map.Entry ) {
239 return new MappedValueExpression(ve, (Map.Entry ) value);
240 }
241 throw new IllegalStateException ("Cannot create VE for: " + src);
242 }
243
244 private final String getVarName(FaceletContext ctx) {
245 if (this.var != null) {
246 return this.var.getValue(ctx);
247 }
248 return null;
249 }
250
251 private final String getVarStatusName(FaceletContext ctx) {
252 if (this.varStatus != null) {
253 return this.varStatus.getValue(ctx);
254 }
255 return null;
256 }
257
258 private final Iterator toIterator(Object src) {
259 if (src == null) {
260 return null;
261 } else if (src instanceof Collection ) {
262 return ((Collection ) src).iterator();
263 } else if (src instanceof Map ) {
264 return ((Map ) src).entrySet().iterator();
265 } else if (src.getClass().isArray()) {
266 return new ArrayIterator(src);
267 } else {
268 throw new TagAttributeException(this.tag, this.items,
269 "Must evaluate to a Collection, Map, Array, or null.");
270 }
271 }
272
273 }
274 |
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