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1
17
18 package javax.servlet.jsp.el;
19
20 import java.beans.FeatureDescriptor  ;
21 import java.util.ArrayList ;
22 import java.util.Collection ;
23 import java.util.Enumeration ;
24 import java.util.Iterator ;
25 import java.util.List ;
26
27 import javax.el.ELContext;
28 import javax.el.ELException;
29 import javax.el.ELResolver;
30 import javax.el.PropertyNotFoundException;
31 import javax.el.PropertyNotWritableException;
32 import javax.servlet.jsp.JspContext ;
33 import javax.servlet.jsp.PageContext ;
34
35 public class ScopedAttributeELResolver extends ELResolver {
36
37 public ScopedAttributeELResolver() {
38 super();
39 }
40
41 public Object getValue(ELContext context, Object base, Object property)
42 throws NullPointerException , PropertyNotFoundException, ELException {
43 if (context == null) {
44 throw new NullPointerException ();
45 }
46
47 if (base == null) {
48 context.setPropertyResolved(true);
49 if (property != null) {
50 String key = property.toString();
51 PageContext page = (PageContext ) context
52 .getContext(JspContext .class);
53 return page.findAttribute(key);
54 }
55 }
56
57 return null;
58 }
59
60 public Class getType(ELContext context, Object base, Object property)
61 throws NullPointerException , PropertyNotFoundException, ELException {
62 if (context == null) {
63 throw new NullPointerException ();
64 }
65
66 if (base == null) {
67 context.setPropertyResolved(true);
68 return Object .class;
69 }
70
71 return null;
72 }
73
74 public void setValue(ELContext context, Object base, Object property,
75 Object value) throws NullPointerException ,
76 PropertyNotFoundException, PropertyNotWritableException,
77 ELException {
78 if (context == null) {
79 throw new NullPointerException ();
80 }
81
82 if (base == null) {
83 context.setPropertyResolved(true);
84 if (property != null) {
85 String key = property.toString();
86 PageContext page = (PageContext ) context
87 .getContext(JspContext .class);
88 int scope = page.getAttributesScope(key);
89 if (scope != 0) {
90 page.setAttribute(key, value, scope);
91 } else {
92 page.setAttribute(key, value);
93 }
94 }
95 }
96 }
97
98 public boolean isReadOnly(ELContext context, Object base, Object property)
99 throws NullPointerException , PropertyNotFoundException, ELException {
100 if (context == null) {
101 throw new NullPointerException ();
102 }
103
104 if (base == null) {
105 context.setPropertyResolved(true);
106 }
107
108 return false;
109 }
110
111 public Iterator <FeatureDescriptor > getFeatureDescriptors(ELContext context, Object base) {
112
113 PageContext ctxt = (PageContext ) context.getContext(JspContext .class);
114 List <FeatureDescriptor > list = new ArrayList <FeatureDescriptor >();
115 Enumeration e;
116 Object value;
117 String name;
118
119 e = ctxt.getAttributeNamesInScope(PageContext.PAGE_SCOPE);
120 while (e.hasMoreElements()) {
121 name = (String ) e.nextElement();
122 value = ctxt.getAttribute(name, PageContext.PAGE_SCOPE);
123 FeatureDescriptor descriptor = new FeatureDescriptor ();
124 descriptor.setName(name);
125 descriptor.setDisplayName(name);
126 descriptor.setExpert(false);
127 descriptor.setHidden(false);
128 descriptor.setPreferred(true);
129 descriptor.setShortDescription("page scoped attribute");
130 descriptor.setValue("type", value.getClass());
131 descriptor.setValue("resolvableAtDesignTime", Boolean.FALSE);
132 list.add(descriptor);
133 }
134
135 e = ctxt.getAttributeNamesInScope(PageContext.REQUEST_SCOPE);
136 while (e.hasMoreElements()) {
137 name = (String ) e.nextElement();
138 value = ctxt.getAttribute(name, PageContext.REQUEST_SCOPE);
139 FeatureDescriptor descriptor = new FeatureDescriptor ();
140 descriptor.setName(name);
141 descriptor.setDisplayName(name);
142 descriptor.setExpert(false);
143 descriptor.setHidden(false);
144 descriptor.setPreferred(true);
145 descriptor.setShortDescription("request scope attribute");
146 descriptor.setValue("type", value.getClass());
147 descriptor.setValue("resolvableAtDesignTime", Boolean.FALSE);
148 list.add(descriptor);
149 }
150
151 if (ctxt.getSession() != null) {
152 e = ctxt.getAttributeNamesInScope(PageContext.SESSION_SCOPE);
153 while (e.hasMoreElements()) {
154 name = (String ) e.nextElement();
155 value = ctxt.getAttribute(name, PageContext.SESSION_SCOPE);
156 FeatureDescriptor descriptor = new FeatureDescriptor ();
157 descriptor.setName(name);
158 descriptor.setDisplayName(name);
159 descriptor.setExpert(false);
160 descriptor.setHidden(false);
161 descriptor.setPreferred(true);
162 descriptor.setShortDescription("session scoped attribute");
163 descriptor.setValue("type", value.getClass());
164 descriptor.setValue("resolvableAtDesignTime", Boolean.FALSE);
165 list.add(descriptor);
166 }
167 }
168
169 e = ctxt.getAttributeNamesInScope(PageContext.APPLICATION_SCOPE);
170 while (e.hasMoreElements()) {
171 name = (String ) e.nextElement();
172 value = ctxt.getAttribute(name, PageContext.APPLICATION_SCOPE);
173 FeatureDescriptor descriptor = new FeatureDescriptor ();
174 descriptor.setName(name);
175 descriptor.setDisplayName(name);
176 descriptor.setExpert(false);
177 descriptor.setHidden(false);
178 descriptor.setPreferred(true);
179 descriptor.setShortDescription("application scoped attribute");
180 descriptor.setValue("type", value.getClass());
181 descriptor.setValue("resolvableAtDesignTime", Boolean.FALSE);
182 list.add(descriptor);
183 }
184 return list.iterator();
185 }
186
187 private static void appendEnumeration(Collection c, Enumeration e) {
188 while (e.hasMoreElements()) {
189 c.add(e.nextElement());
190 }
191 }
192
193 public Class <String > getCommonPropertyType(ELContext context, Object base) {
194 if (base == null) {
195 return String .class;
196 }
197 return null;
198 }
199 }
200 |
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