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1
17 package org.apache.jasper.runtime;
18
19 import java.util.ArrayList  ;
20 import java.util.Iterator ;
21 import java.util.List ;
22
23 import javax.el.ArrayELResolver;
24 import javax.el.BeanELResolver;
25 import javax.el.CompositeELResolver;
26 import javax.el.ELContextEvent;
27 import javax.el.ELContextListener;
28 import javax.el.ELResolver;
29 import javax.el.ExpressionFactory;
30 import javax.el.ListELResolver;
31 import javax.el.MapELResolver;
32 import javax.el.ResourceBundleELResolver;
33 import javax.servlet.ServletContext ;
34 import javax.servlet.jsp.JspApplicationContext ;
35 import javax.servlet.jsp.JspContext ;
36 import javax.servlet.jsp.el.ImplicitObjectELResolver ;
37 import javax.servlet.jsp.el.ScopedAttributeELResolver ;
38
39 import org.apache.el.ExpressionFactoryImpl;
40 import org.apache.jasper.el.ELContextImpl;
41
42
47 public class JspApplicationContextImpl implements JspApplicationContext {
48
49 private final static String KEY = JspApplicationContextImpl.class.getName();
50
51 private final static ExpressionFactory expressionFactory = new ExpressionFactoryImpl();
52
53 private final List <ELContextListener> contextListeners = new ArrayList <ELContextListener>();
54
55 private final List <ELResolver> resolvers = new ArrayList <ELResolver>();
56
57 private boolean instantiated = false;
58
59 private ELResolver resolver;
60
61 public JspApplicationContextImpl() {
62
63 }
64
65 public void addELContextListener(ELContextListener listener) {
66 if (listener == null) {
67 throw new IllegalArgumentException ("ELConextListener was null");
68 }
69 this.contextListeners.add(listener);
70 }
71
72 public static JspApplicationContextImpl getInstance(ServletContext context) {
73 if (context == null) {
74 throw new IllegalArgumentException ("ServletContext was null");
75 }
76 JspApplicationContextImpl impl = (JspApplicationContextImpl) context
77 .getAttribute(KEY);
78 if (impl == null) {
79 impl = new JspApplicationContextImpl();
80 context.setAttribute(KEY, impl);
81 }
82 return impl;
83 }
84
85 public ELContextImpl createELContext(JspContext context) {
86 if (context == null) {
87 throw new IllegalArgumentException ("JspContext was null");
88 }
89
90 ELResolver r = this.createELResolver();
92 ELContextImpl ctx = new ELContextImpl(r);
93 ctx.putContext(JspContext .class, context);
94
95 ELContextEvent event = new ELContextEvent(ctx);
97 for (int i = 0; i < this.contextListeners.size(); i++) {
98 this.contextListeners.get(i).contextCreated(event);
99 }
100
101 return ctx;
102 }
103
104 private ELResolver createELResolver() {
105 this.instantiated = true;
106 if (this.resolver == null) {
107 CompositeELResolver r = new CompositeELResolver();
108 r.add(new ImplicitObjectELResolver ());
109 for (Iterator itr = this.resolvers.iterator(); itr.hasNext();) {
110 r.add((ELResolver) itr.next());
111 }
112 r.add(new MapELResolver());
113 r.add(new ResourceBundleELResolver());
114 r.add(new ListELResolver());
115 r.add(new ArrayELResolver());
116 r.add(new BeanELResolver());
117 r.add(new ScopedAttributeELResolver ());
118 this.resolver = r;
119 }
120 return this.resolver;
121 }
122
123 public void addELResolver(ELResolver resolver) throws IllegalStateException {
124 if (resolver == null) {
125 throw new IllegalArgumentException ("ELResolver was null");
126 }
127 if (this.instantiated) {
128 throw new IllegalStateException (
129 "cannot call addELResolver after the first request has been made");
130 }
131 this.resolvers.add(resolver);
132 }
133
134 public ExpressionFactory getExpressionFactory() {
135 return expressionFactory;
136 }
137
138 }
139 |
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