01: /*
02: * Copyright 2004-2007 the original author or authors.
03: *
04: * Licensed under the Apache License, Version 2.0 (the "License");
05: * you may not use this file except in compliance with the License.
06: * You may obtain a copy of the License at
07: *
08: * http://www.apache.org/licenses/LICENSE-2.0
09: *
10: * Unless required by applicable law or agreed to in writing, software
11: * distributed under the License is distributed on an "AS IS" BASIS,
12: * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13: * See the License for the specific language governing permissions and
14: * limitations under the License.
15: */
16: package org.springframework.webflow.engine.support;
17:
18: import java.io.Serializable;
19:
20: import org.springframework.binding.expression.Expression;
21: import org.springframework.core.style.ToStringCreator;
22: import org.springframework.webflow.engine.ViewSelector;
23: import org.springframework.webflow.execution.RequestContext;
24: import org.springframework.webflow.execution.ViewSelection;
25: import org.springframework.webflow.execution.support.ExternalRedirect;
26:
27: /**
28: * Makes view selections requesting a client side redirect to an <i>external</i>
29: * URL outside of the flow.
30: * <p>
31: * This selector is usefull when you wish to request a <i>redirect after
32: * conversation completion</i> as part of entering an EndState.
33: * <p>
34: * This selector may also be used to redirect to an external URL from a
35: * ViewState of an active conversation. The external system redirected to will
36: * be provided the flow execution context necessary to allow it to communicate
37: * back to the executing flow at a later time.
38: *
39: * @see org.springframework.webflow.execution.support.ExternalRedirect
40: *
41: * @author Keith Donald
42: * @author Erwin Vervaet
43: */
44: public class ExternalRedirectSelector implements ViewSelector,
45: Serializable {
46:
47: /**
48: * The parsed, evaluatable redirect URL expression.
49: */
50: private Expression urlExpression;
51:
52: /**
53: * Create a new redirecting view selector that takes given URL expression as
54: * input. The expression is the parsed form (expression-tokenized) of the
55: * encoded view (e.g. "/pathInfo?param0=value0¶m1=value1").
56: * @param urlExpression the url expression
57: */
58: public ExternalRedirectSelector(Expression urlExpression) {
59: this .urlExpression = urlExpression;
60: }
61:
62: /**
63: * Returns the expression used by this view selector.
64: */
65: public Expression getUrlExpression() {
66: return urlExpression;
67: }
68:
69: public boolean isEntrySelectionRenderable(RequestContext context) {
70: return true;
71: }
72:
73: public ViewSelection makeEntrySelection(RequestContext context) {
74: String url = (String) urlExpression.evaluate(context, null);
75: return new ExternalRedirect(url);
76: }
77:
78: public ViewSelection makeRefreshSelection(RequestContext context) {
79: return makeEntrySelection(context);
80: }
81:
82: public String toString() {
83: return new ToStringCreator(this ).append("urlExpression",
84: urlExpression).toString();
85: }
86: }
|