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12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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17  * You should have received a copy of the GNU General Public License version
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25 
26 package jdk.nashorn.internal.ir;
27 
28 /**
29  * Statement is something that becomes code and can be stepped past. A block is
30  * made up of statements. The only node subclass that needs to keep token and
31  * location information is the Statement
32  */
33 public abstract class Statement extends Node implements Terminal {
34     private static final long serialVersionUID = 1L;
35 
36     private final int lineNumber;
37 
38     /**
39      * Constructor
40      *
41      * @param lineNumber line number
42      * @param token      token
43      * @param finish     finish
44      */
Statement(final int lineNumber, final long token, final int finish)45     public Statement(final int lineNumber, final long token, final int finish) {
46         super(token, finish);
47         this.lineNumber = lineNumber;
48     }
49 
50     /**
51      * Constructor
52      *
53      * @param lineNumber line number
54      * @param token      token
55      * @param start      start
56      * @param finish     finish
57      */
Statement(final int lineNumber, final long token, final int start, final int finish)58     protected Statement(final int lineNumber, final long token, final int start, final int finish) {
59         super(token, start, finish);
60         this.lineNumber = lineNumber;
61     }
62 
63     /**
64      * Copy constructor
65      *
66      * @param node source node
67      */
Statement(final Statement node)68     protected Statement(final Statement node) {
69         super(node);
70         this.lineNumber = node.lineNumber;
71     }
72 
73     /**
74      * Return the line number
75      * @return line number
76      */
getLineNumber()77     public int getLineNumber() {
78         return lineNumber;
79     }
80 
81     /**
82      * Is this a terminal statement, i.e. does it end control flow like a throw or return?
83      *
84      * @return true if this node statement is terminal
85      */
86     @Override
isTerminal()87     public boolean isTerminal() {
88         return false;
89     }
90 
91     /**
92      * Check if this statement repositions control flow with goto like
93      * semantics, for example {@link BreakNode} or a {@link ForNode} with no test
94      * @return true if statement has goto semantics
95      */
hasGoto()96     public boolean hasGoto() {
97         return false;
98     }
99 
100     /**
101      * Check if this statement has terminal flags, i.e. ends or breaks control flow
102      *
103      * @return true if has terminal flags
104      */
hasTerminalFlags()105     public final boolean hasTerminalFlags() {
106         return isTerminal() || hasGoto();
107     }
108 }
109 
110