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  */
  25 
  26 package jdk.nashorn.internal.ir;
  27 
  28 import jdk.nashorn.internal.codegen.types.Type;
  29 import jdk.nashorn.internal.ir.annotations.Immutable;
  30 import jdk.nashorn.internal.ir.visitor.NodeVisitor;
  31 import jdk.nashorn.internal.parser.Token;
  32 import jdk.nashorn.internal.parser.TokenType;
  33 
  34 /**
  35  * IR representation of a property access (period operator.)
  36  */
  37 @Immutable
  38 public final class AccessNode extends BaseNode {
  39     private static final long serialVersionUID = 1L;
  40 
  41     /** Property name. */
  42     private final String property;
  43 
  44     /**
  45      * Constructor
  46      *
  47      * @param token     token
  48      * @param finish    finish
  49      * @param base      base node
  50      * @param property  property
  51      */
  52     public AccessNode(final long token, final int finish, final Expression base, final String property) {
  53         super(token, finish, base, false);
  54         this.property = property;
  55     }
  56 
  57     private AccessNode(final AccessNode accessNode, final Expression base, final String property, final boolean isFunction, final Type type, final int id) {
  58         super(accessNode, base, isFunction, type, id);
  59         this.property = property;
  60     }
  61 
  62     /**
  63      * Assist in IR navigation.
  64      * @param visitor IR navigating visitor.
  65      */
  66     @Override
  67     public Node accept(final NodeVisitor<? extends LexicalContext> visitor) {
  68         if (visitor.enterAccessNode(this)) {
  69             return visitor.leaveAccessNode(
  70                 setBase((Expression)base.accept(visitor)));
  71         }
  72         return this;
  73     }
  74 
  75     @Override
  76     public void toString(final StringBuilder sb, final boolean printType) {
  77         final boolean needsParen = tokenType().needsParens(getBase().tokenType(), true);
  78 
  79         if (printType) {
  80             optimisticTypeToString(sb);
  81         }
  82 
  83         if (needsParen) {
  84             sb.append('(');
  85         }
  86 
  87         base.toString(sb, printType);
  88 
  89         if (needsParen) {
  90             sb.append(')');
  91         }
  92         sb.append('.');
  93 
  94         sb.append(property);
  95     }
  96 
  97     /**
  98      * Get the property name
  99      *
 100      * @return the property name
 101      */
 102     public String getProperty() {
 103         return property;
 104     }
 105 
 106     /**
 107      * Return true if this node represents an index operation normally represented as {@link IndexNode}.
 108      * @return true if an index access.
 109      */
 110     public boolean isIndex() {
 111         return Token.descType(getToken()) == TokenType.LBRACKET;
 112     }
 113 
 114     private AccessNode setBase(final Expression base) {
 115         if (this.base == base) {
 116             return this;
 117         }
 118         return new AccessNode(this, base, property, isFunction(), type, programPoint);
 119     }
 120 
 121     @Override
 122     public AccessNode setType(final Type type) {
 123         if (this.type == type) {
 124             return this;
 125         }
 126         return new AccessNode(this, base, property, isFunction(), type, programPoint);
 127     }
 128 
 129     @Override
 130     public AccessNode setProgramPoint(final int programPoint) {
 131         if (this.programPoint == programPoint) {
 132             return this;
 133         }
 134         return new AccessNode(this, base, property, isFunction(), type, programPoint);
 135     }
 136 
 137     @Override
 138     public AccessNode setIsFunction() {
 139         if (isFunction()) {
 140             return this;
 141         }
 142         return new AccessNode(this, base, property, true, type, programPoint);
 143     }
 144 }