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.ir.annotations.Immutable;
29 import jdk.nashorn.internal.ir.visitor.NodeVisitor;
30
31 /**
32 * IR representation of a catch clause.
33 */
34 @Immutable
35 public final class CatchNode extends Statement {
36 private static final long serialVersionUID = 1L;
37
38 /** Exception identifier. */
39 private final IdentNode exception;
40
41 /** Exception condition. */
42 private final Expression exceptionCondition;
43
44 /** Catch body. */
45 private final Block body;
46
47 private final boolean isSyntheticRethrow;
48
49 /**
50 * Constructors
51 *
52 * @param lineNumber lineNumber
53 * @param token token
54 * @param finish finish
55 * @param exception variable name of exception
56 * @param exceptionCondition exception condition
57 * @param body catch body
58 * @param isSyntheticRethrow true if this node is a synthetically generated rethrow node.
59 */
60 public CatchNode(final int lineNumber, final long token, final int finish, final IdentNode exception,
61 final Expression exceptionCondition, final Block body, final boolean isSyntheticRethrow) {
62 super(lineNumber, token, finish);
63 this.exception = exception == null ? null : exception.setIsInitializedHere();
64 this.exceptionCondition = exceptionCondition;
65 this.body = body;
66 this.isSyntheticRethrow = isSyntheticRethrow;
67 }
68
69 private CatchNode(final CatchNode catchNode, final IdentNode exception, final Expression exceptionCondition,
70 final Block body, final boolean isSyntheticRethrow) {
71 super(catchNode);
72 this.exception = exception;
73 this.exceptionCondition = exceptionCondition;
74 this.body = body;
75 this.isSyntheticRethrow = isSyntheticRethrow;
76 }
77
78 /**
79 * Assist in IR navigation.
80 * @param visitor IR navigating visitor.
81 */
82 @Override
83 public Node accept(final NodeVisitor<? extends LexicalContext> visitor) {
84 if (visitor.enterCatchNode(this)) {
85 return visitor.leaveCatchNode(
86 setException((IdentNode)exception.accept(visitor)).
87 setExceptionCondition(exceptionCondition == null ? null : (Expression)exceptionCondition.accept(visitor)).
88 setBody((Block)body.accept(visitor)));
89 }
90
91 return this;
92 }
93
94 @Override
95 public boolean isTerminal() {
96 return body.isTerminal();
97 }
98
99 @Override
100 public void toString(final StringBuilder sb, final boolean printTypes) {
101 sb.append(" catch (");
102 exception.toString(sb, printTypes);
103
104 if (exceptionCondition != null) {
105 sb.append(" if ");
106 exceptionCondition.toString(sb, printTypes);
107 }
108 sb.append(')');
109 }
110
111 /**
112 * Get the identifier representing the exception thrown
113 * @return the exception identifier
114 */
115 public IdentNode getException() {
116 return exception;
117 }
118
119 /**
120 * Get the exception condition for this catch block
121 * @return the exception condition
122 */
123 public Expression getExceptionCondition() {
124 return exceptionCondition;
125 }
126
127 /**
128 * Reset the exception condition for this catch block
129 * @param exceptionCondition the new exception condition
130 * @return new or same CatchNode
131 */
132 public CatchNode setExceptionCondition(final Expression exceptionCondition) {
133 if (this.exceptionCondition == exceptionCondition) {
134 return this;
135 }
136 return new CatchNode(this, exception, exceptionCondition, body, isSyntheticRethrow);
137 }
138
139 /**
140 * Get the body for this catch block
141 * @return the catch block body
142 */
143 public Block getBody() {
144 return body;
145 }
146
147 /**
148 * Resets the exception of a catch block
149 * @param exception new exception
150 * @return new catch node if changed, same otherwise
151 */
152 public CatchNode setException(final IdentNode exception) {
153 if (this.exception == exception) {
154 return this;
155 }
156 return new CatchNode(this, exception, exceptionCondition, body, isSyntheticRethrow);
157 }
158
159 private CatchNode setBody(final Block body) {
160 if (this.body == body) {
161 return this;
162 }
163 return new CatchNode(this, exception, exceptionCondition, body, isSyntheticRethrow);
164 }
165
166 /**
167 * Is this catch block a non-JavaScript constructor, for example created as
168 * part of the rethrow mechanism of a finally block in Lower? Then we just
169 * pass the exception on and need not unwrap whatever is in the ECMAException
170 * object catch symbol
171 * @return true if a finally synthetic rethrow
172 */
173 public boolean isSyntheticRethrow() {
174 return isSyntheticRethrow;
175 }
176 }