jdk8-mips64-public/nashorn: src/jdk/nashorn/internal/ir/ReturnNode.java@6fc7b51e83d6

8012522: Clean up lexical contexts - split out stack based functionality in CodeGenerator and generify NodeVisitors based on their LexicalContext type to avoid casts
Reviewed-by: attila, jlaskey

     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

     6  * under the terms of the GNU General Public License version 2 only, as

     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

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    26 package jdk.nashorn.internal.ir;

    28 import static jdk.nashorn.internal.parser.TokenType.RETURN;

    29 import static jdk.nashorn.internal.parser.TokenType.YIELD;

    30 import jdk.nashorn.internal.ir.annotations.Immutable;

    31 import jdk.nashorn.internal.ir.visitor.NodeVisitor;

    33 /**

    34  * IR representation for RETURN or YIELD statements.

    35  */

    36 @Immutable

    37 public class ReturnNode extends Statement {

    38     /** Optional expression. */

    39     private final Node expression;

    41     /**

    42      * Constructor

    43      *

    44      * @param lineNumber line number

    45      * @param token      token

    46      * @param finish     finish

    47      * @param expression expression to return

    48      */

    49     public ReturnNode(final int lineNumber, final long token, final int finish, final Node expression) {

    50         super(lineNumber, token, finish);

    51         this.expression = expression;

    52     }

    54     private ReturnNode(final ReturnNode returnNode, final Node expression) {

    55         super(returnNode);

    56         this.expression = expression;

    57     }

    59     @Override

    60     public boolean isTerminal() {

    61         return true;

    62     }

    64     /**

    65      * Return true if is a RETURN node.

    66      * @return true if is RETURN node.

    67      */

    68     public boolean isReturn() {

    69         return isTokenType(RETURN);

    70     }

    72     /**

    73      * Check if this return node has an expression

    74      * @return true if not a void return

    75      */

    76     public boolean hasExpression() {

    77         return expression != null;

    78     }

    80     /**

    81      * Return true if is a YIELD node.

    82      * @return TRUE if is YIELD node.

    83      */

    84     public boolean isYield() {

    85         return isTokenType(YIELD);

    86     }

    88     @Override

    89     public Node accept(final NodeVisitor<? extends LexicalContext> visitor) {

    90         if (visitor.enterReturnNode(this)) {

    91             if (expression != null) {

    92                 return visitor.leaveReturnNode(setExpression(expression.accept(visitor)));

    93             }

    94             return visitor.leaveReturnNode(this);

    95         }

    97         return this;

    98     }

   101     @Override

   102     public void toString(final StringBuilder sb) {

   103         sb.append(isYield() ? "yield" : "return");

   104         if (expression != null) {

   105             sb.append(' ');

   106             expression.toString(sb);

   107         }

   108     }

   110     /**

   111      * Get the expression this node returns

   112      * @return return expression, or null if void return

   113      */

   114     public Node getExpression() {

   115         return expression;

   116     }

   118     /**

   119      * Reset the expression this node returns

   120      * @param expression new expression, or null if void return

   121      * @return new or same return node

   122      */

   123     public ReturnNode setExpression(final Node expression) {

   124         if (this.expression == expression) {

   125             return this;

   126         }

   127         return new ReturnNode(this, expression);

   128     }

   130 }

Mercurial > jdk8-mips64-public > nashorn / file revision

src/jdk/nashorn/internal/ir/ReturnNode.java@6fc7b51e83d6

src/jdk/nashorn/internal/ir/ReturnNode.java