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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
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17  * You should have received a copy of the GNU General Public License version
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24  */
25 
26 package jdk.nashorn.internal.ir;
27 
28 import java.util.List;
29 import jdk.nashorn.internal.ir.visitor.NodeVisitor;
30 
31 /**
32  * Represents a block used as a statement.
33  */
34 public class BlockStatement extends Statement {
35     private static final long serialVersionUID = 1L;
36 
37     /** Block to execute. */
38     private final Block block;
39 
40     /**
41      * Constructor
42      *
43      * @param block the block to execute
44      */
BlockStatement(final Block block)45     public BlockStatement(final Block block) {
46         this(block.getFirstStatementLineNumber(), block);
47     }
48 
49     /**
50      * Constructor
51      *
52      * @param lineNumber line number
53      * @param block the block to execute
54      */
BlockStatement(final int lineNumber, final Block block)55     public BlockStatement(final int lineNumber, final Block block) {
56         super(lineNumber, block.getToken(), block.getFinish());
57         this.block = block;
58     }
59 
BlockStatement(final BlockStatement blockStatement, final Block block)60     private BlockStatement(final BlockStatement blockStatement, final Block block) {
61         super(blockStatement);
62         this.block = block;
63     }
64 
65     /**
66      * Use this method to create a block statement meant to replace a single statement.
67      * @param stmt the statement to replace
68      * @param newStmts the statements for the new block statement
69      * @return a block statement with the new statements. It will have the line number, token, and finish of the
70      * original statement.
71      */
createReplacement(final Statement stmt, final List<Statement> newStmts)72     public static BlockStatement createReplacement(final Statement stmt, final List<Statement> newStmts) {
73         return createReplacement(stmt, stmt.getFinish(), newStmts);
74     }
75 
76     /**
77      * Use this method to create a block statement meant to replace a single statement.
78      * @param stmt the statement to replace
79      * @param finish the new finish for the block
80      * @param newStmts the statements for the new block statement
81      * @return a block statement with the new statements. It will have the line number, and token of the
82      * original statement.
83      */
createReplacement(final Statement stmt, final int finish, final List<Statement> newStmts)84     public static BlockStatement createReplacement(final Statement stmt, final int finish, final List<Statement> newStmts) {
85         return new BlockStatement(stmt.getLineNumber(), new Block(stmt.getToken(), finish, newStmts));
86     }
87 
88     @Override
isTerminal()89     public boolean isTerminal() {
90         return block.isTerminal();
91     }
92 
93     /**
94      * Tells if this is a synthetic block statement or not.
95      *
96      * @return true if this is a synthetic statement
97      */
isSynthetic()98     public boolean isSynthetic() {
99         return block.isSynthetic();
100     }
101 
102     @Override
accept(final NodeVisitor<? extends LexicalContext> visitor)103     public Node accept(final NodeVisitor<? extends LexicalContext> visitor) {
104         if (visitor.enterBlockStatement(this)) {
105             return visitor.leaveBlockStatement(setBlock((Block)block.accept(visitor)));
106         }
107 
108         return this;
109     }
110 
111     @Override
toString(final StringBuilder sb, final boolean printType)112     public void toString(final StringBuilder sb, final boolean printType) {
113         block.toString(sb, printType);
114     }
115 
116     /**
117      * Return the block to be executed
118      * @return the block
119      */
getBlock()120     public Block getBlock() {
121         return block;
122     }
123 
124     /**
125      * Reset the block to be executed
126      * @param block the block
127      * @return new or same execute node
128      */
setBlock(final Block block)129     public BlockStatement setBlock(final Block block) {
130         if (this.block == block) {
131             return this;
132         }
133         return new BlockStatement(this, block);
134     }
135 }
136