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1   /*
2    * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4    *
5    * This code is free software; you can redistribute it and/or modify it
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7    * published by the Free Software Foundation.  Oracle designates this
8    * particular file as subject to the "Classpath" exception as provided
9    * by Oracle in the LICENSE file that accompanied this code.
10   *
11   * This code is distributed in the hope that it will be useful, but WITHOUT
12   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14   * version 2 for more details (a copy is included in the LICENSE file that
15   * accompanied this code).
16   *
17   * You should have received a copy of the GNU General Public License version
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19   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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25  
26  package jdk.nashorn.internal.ir;
27  
28  import java.util.List;
29  import jdk.nashorn.internal.codegen.Label;
30  
31  /**
32   * This class represents a node from which control flow can execute
33   * a {@code break} statement
34   */
35  public interface BreakableNode extends LexicalContextNode {
36      /**
37       * Ensure that any labels in this breakable node are unique so
38       * that new jumps won't go to old parts of the tree. Used for
39       * example for cloning finally blocks
40       *
41       * @param lc the lexical context
42       * @return node after labels have been made unique
43       */
44      public abstract Node ensureUniqueLabels(final LexicalContext lc);
45  
46      /**
47       * Check whether this can be broken out from without using a label,
48       * e.g. everything but Blocks, basically
49       * @return true if breakable without label
50       */
51      public boolean isBreakableWithoutLabel();
52  
53      /**
54       * Return the break label, i.e. the location to go to on break.
55       * @return the break label
56       */
57      public Label getBreakLabel();
58  
59      /**
60       * Return the labels associated with this node. Breakable nodes that
61       * aren't LoopNodes only have a break label - the location immediately
62       * afterwards the node in code
63       * @return list of labels representing locations around this node
64       */
65      public List<Label> getLabels();
66  }