File: JspApplicationContextImpl.java

package info (click to toggle)
tomcat7 7.0.56-3%2Bdeb8u11
  • links: PTS, VCS
  • area: main
  • in suites: jessie
  • size: 35,688 kB
  • ctags: 41,823
  • sloc: java: 249,464; xml: 51,553; jsp: 3,037; sh: 1,361; perl: 269; makefile: 195
file content (138 lines) | stat: -rw-r--r-- 4,587 bytes parent folder | download | duplicates (3)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.jasper.runtime;

import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.ArrayList;
import java.util.List;

import javax.el.CompositeELResolver;
import javax.el.ELContextEvent;
import javax.el.ELContextListener;
import javax.el.ELResolver;
import javax.el.ExpressionFactory;
import javax.servlet.ServletContext;
import javax.servlet.jsp.JspApplicationContext;
import javax.servlet.jsp.JspContext;

import org.apache.jasper.Constants;
import org.apache.jasper.el.ELContextImpl;
import org.apache.jasper.el.JasperELResolver;

/**
 * Implementation of JspApplicationContext
 *
 * @author Jacob Hookom
 */
public class JspApplicationContextImpl implements JspApplicationContext {

    private static final String KEY = JspApplicationContextImpl.class.getName();

    private final ExpressionFactory expressionFactory =
            ExpressionFactory.newInstance();

    private final List<ELContextListener> contextListeners = new ArrayList<ELContextListener>();

    private final List<ELResolver> resolvers = new ArrayList<ELResolver>();

    private boolean instantiated = false;

    private ELResolver resolver;

    public JspApplicationContextImpl() {

    }

    @Override
    public void addELContextListener(ELContextListener listener) {
        if (listener == null) {
            throw new IllegalArgumentException("ELConextListener was null");
        }
        this.contextListeners.add(listener);
    }

    public static JspApplicationContextImpl getInstance(ServletContext context) {
        if (context == null) {
            throw new IllegalArgumentException("ServletContext was null");
        }
        JspApplicationContextImpl impl = (JspApplicationContextImpl) context
                .getAttribute(KEY);
        if (impl == null) {
            impl = new JspApplicationContextImpl();
            context.setAttribute(KEY, impl);
        }
        return impl;
    }

    public ELContextImpl createELContext(JspContext context) {
        if (context == null) {
            throw new IllegalArgumentException("JspContext was null");
        }

        // create ELContext for JspContext
        final ELResolver r = this.createELResolver();
        ELContextImpl ctx;
        if (Constants.IS_SECURITY_ENABLED) {
            ctx = AccessController.doPrivileged(
                    new PrivilegedAction<ELContextImpl>() {
                        @Override
                        public ELContextImpl run() {
                            return new ELContextImpl(r);
                        }
                    });
        } else {
            ctx = new ELContextImpl(r);
        }
        ctx.putContext(JspContext.class, context);

        // alert all ELContextListeners
        ELContextEvent event = new ELContextEvent(ctx);
        for (int i = 0; i < this.contextListeners.size(); i++) {
            this.contextListeners.get(i).contextCreated(event);
        }

        return ctx;
    }

    private ELResolver createELResolver() {
        this.instantiated = true;
        if (this.resolver == null) {
            CompositeELResolver r = new JasperELResolver(this.resolvers);
            this.resolver = r;
        }
        return this.resolver;
    }

    @Override
    public void addELResolver(ELResolver resolver) throws IllegalStateException {
        if (resolver == null) {
            throw new IllegalArgumentException("ELResolver was null");
        }
        if (this.instantiated) {
            throw new IllegalStateException(
                    "cannot call addELResolver after the first request has been made");
        }
        this.resolvers.add(resolver);
    }

    @Override
    public ExpressionFactory getExpressionFactory() {
        return expressionFactory;
    }

}