| /* |
| * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package jdk.nashorn.internal.ir; |
| |
| import jdk.nashorn.internal.codegen.types.Type; |
| import jdk.nashorn.internal.ir.annotations.Immutable; |
| import jdk.nashorn.internal.ir.visitor.NodeVisitor; |
| import jdk.nashorn.internal.parser.TokenType; |
| |
| /** |
| * TernaryNode represent the ternary operator {@code ?:}. Note that for control-flow calculation reasons its branch |
| * expressions (but not its test expression) are always wrapped in instances of {@link JoinPredecessorExpression}. |
| */ |
| @Immutable |
| public final class TernaryNode extends Expression { |
| private static final long serialVersionUID = 1L; |
| |
| private final Expression test; |
| private final JoinPredecessorExpression trueExpr; |
| private final JoinPredecessorExpression falseExpr; |
| |
| /** |
| * Constructor |
| * |
| * @param token token |
| * @param test test expression |
| * @param trueExpr expression evaluated when test evaluates to true |
| * @param falseExpr expression evaluated when test evaluates to true |
| */ |
| public TernaryNode(final long token, final Expression test, final JoinPredecessorExpression trueExpr, final JoinPredecessorExpression falseExpr) { |
| super(token, falseExpr.getFinish()); |
| this.test = test; |
| this.trueExpr = trueExpr; |
| this.falseExpr = falseExpr; |
| } |
| |
| private TernaryNode(final TernaryNode ternaryNode, final Expression test, final JoinPredecessorExpression trueExpr, |
| final JoinPredecessorExpression falseExpr) { |
| super(ternaryNode); |
| this.test = test; |
| this.trueExpr = trueExpr; |
| this.falseExpr = falseExpr; |
| } |
| |
| @Override |
| public Node accept(final NodeVisitor<? extends LexicalContext> visitor) { |
| if (visitor.enterTernaryNode(this)) { |
| final Expression newTest = (Expression)getTest().accept(visitor); |
| final JoinPredecessorExpression newTrueExpr = (JoinPredecessorExpression)trueExpr.accept(visitor); |
| final JoinPredecessorExpression newFalseExpr = (JoinPredecessorExpression)falseExpr.accept(visitor); |
| return visitor.leaveTernaryNode(setTest(newTest).setTrueExpression(newTrueExpr).setFalseExpression(newFalseExpr)); |
| } |
| |
| return this; |
| } |
| |
| @Override |
| public void toString(final StringBuilder sb, final boolean printType) { |
| final TokenType tokenType = tokenType(); |
| final boolean testParen = tokenType.needsParens(getTest().tokenType(), true); |
| final boolean trueParen = tokenType.needsParens(getTrueExpression().tokenType(), false); |
| final boolean falseParen = tokenType.needsParens(getFalseExpression().tokenType(), false); |
| |
| if (testParen) { |
| sb.append('('); |
| } |
| getTest().toString(sb, printType); |
| if (testParen) { |
| sb.append(')'); |
| } |
| |
| sb.append(" ? "); |
| |
| if (trueParen) { |
| sb.append('('); |
| } |
| getTrueExpression().toString(sb, printType); |
| if (trueParen) { |
| sb.append(')'); |
| } |
| |
| sb.append(" : "); |
| |
| if (falseParen) { |
| sb.append('('); |
| } |
| getFalseExpression().toString(sb, printType); |
| if (falseParen) { |
| sb.append(')'); |
| } |
| } |
| |
| @Override |
| public boolean isLocal() { |
| return getTest().isLocal() |
| && getTrueExpression().isLocal() |
| && getFalseExpression().isLocal(); |
| } |
| |
| @Override |
| public Type getType() { |
| return Type.widestReturnType(getTrueExpression().getType(), getFalseExpression().getType()); |
| } |
| |
| |
| /** |
| * Get the test expression for this ternary expression, i.e. "x" in x ? y : z |
| * @return the test expression |
| */ |
| public Expression getTest() { |
| return test; |
| } |
| |
| /** |
| * Get the true expression for this ternary expression, i.e. "y" in x ? y : z |
| * @return the true expression |
| */ |
| public JoinPredecessorExpression getTrueExpression() { |
| return trueExpr; |
| } |
| |
| /** |
| * Get the false expression for this ternary expression, i.e. "z" in x ? y : z |
| * @return the false expression |
| */ |
| public JoinPredecessorExpression getFalseExpression() { |
| return falseExpr; |
| } |
| |
| /** |
| * Set the test expression for this node |
| * @param test new test expression |
| * @return a node equivalent to this one except for the requested change. |
| */ |
| public TernaryNode setTest(final Expression test) { |
| if (this.test == test) { |
| return this; |
| } |
| return new TernaryNode(this, test, trueExpr, falseExpr); |
| } |
| |
| /** |
| * Set the true expression for this node |
| * @param trueExpr new true expression |
| * @return a node equivalent to this one except for the requested change. |
| */ |
| public TernaryNode setTrueExpression(final JoinPredecessorExpression trueExpr) { |
| if (this.trueExpr == trueExpr) { |
| return this; |
| } |
| return new TernaryNode(this, test, trueExpr, falseExpr); |
| } |
| |
| /** |
| * Set the false expression for this node |
| * @param falseExpr new false expression |
| * @return a node equivalent to this one except for the requested change. |
| */ |
| public TernaryNode setFalseExpression(final JoinPredecessorExpression falseExpr) { |
| if (this.falseExpr == falseExpr) { |
| return this; |
| } |
| return new TernaryNode(this, test, trueExpr, falseExpr); |
| } |
| } |