1// Copyright (c) 2011, Mike Samuel
2// All rights reserved.
3//
4// Redistribution and use in source and binary forms, with or without
5// modification, are permitted provided that the following conditions
6// are met:
7//
8// Redistributions of source code must retain the above copyright
9// notice, this list of conditions and the following disclaimer.
10// Redistributions in binary form must reproduce the above copyright
11// notice, this list of conditions and the following disclaimer in the
12// documentation and/or other materials provided with the distribution.
13// Neither the name of the OWASP nor the names of its contributors may
14// be used to endorse or promote products derived from this software
15// without specific prior written permission.
16// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
19// FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
20// COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
21// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
22// BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
24// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
26// ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27// POSSIBILITY OF SUCH DAMAGE.
28
29package org.owasp.html;
30
31import com.google.common.base.Throwables;
32
33/**
34 * Receives notification of problems.
35 *
36 * @author Mike Samuel <mikesamuel@gmail.com>
37 */
38public interface Handler<T> {
39
40  void handle(T x);
41
42  /** A handler that does nothing given any input. */
43  public static final Handler<Object> DO_NOTHING = new Handler<Object>() {
44    public void handle(Object x) {
45      // Really, do nothing.
46    }
47  };
48
49  /**
50   * A handler that re-raises an error, wrapping it in a runtime exception if
51   * necessary.
52   */
53  public static final Handler<Throwable> PROPAGATE = new Handler<Throwable>() {
54    public void handle(Throwable th) {
55      Throwables.propagate(th);
56    }
57  };
58}
59