1 /*
2 * Licensed under the Apache License, Version 2.0 (the "License");
3 * you may not use this file except in compliance with the License.
4 * You may obtain a copy of the License at
5 *
6 * http://www.apache.org/licenses/LICENSE-2.0
7 *
8 * Unless required by applicable law or agreed to in writing, software
9 * distributed under the License is distributed on an "AS IS" BASIS,
10 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
11 * See the License for the specific language governing permissions and
12 * limitations under the License.
13 *
14 */
15 package org.esigate.parser.future;
16
17 import java.io.IOException;
18 import java.util.concurrent.Future;
19
20 import org.esigate.HttpErrorPage;
21
22 /**
23 * An element represents a tag inside a document.
24 *
25 * <p>
26 * This class is based on Element
27 *
28 * @see org.esigate.parser.Element
29 * @author Nicolas Richeton
30 *
31 */
32 public interface FutureElement {
33 /**
34 * Method called by the parser when it finds an opening tag.
35 *
36 * @param tag
37 * The tag
38 * @param ctx
39 * The parser context
40 * @return true if the body of this tag should be evaluated
41 * @throws IOException
42 * @throws HttpErrorPage
43 */
44 boolean onTagStart(String tag, FutureParserContext ctx) throws IOException, HttpErrorPage;
45
46 /**
47 * Method called by the parser when it finds the matching closing tag.
48 *
49 * @param tag
50 * The tag
51 * @param ctx
52 * @throws IOException
53 * @throws HttpErrorPage
54 */
55 void onTagEnd(String tag, FutureParserContext ctx) throws IOException, HttpErrorPage;
56
57 /**
58 * @param e
59 * @param ctx
60 * @return <code>true</code> if error has been handled by this element and it should not be propagated further.
61 */
62 boolean onError(Exception e, FutureParserContext ctx);
63
64 /**
65 * Method called by the parser when it finds characters between starting and closing tags.
66 *
67 * @param csq
68 * @throws IOException
69 */
70 void characters(Future<CharSequence> csq) throws IOException;
71
72 /**
73 * Get the parent element of this element.
74 *
75 * @return the parent Element or null if this item is the Root element.
76 */
77 FutureElement getParent();
78 }