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 or pattern. */
39 private final Expression 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 or pattern 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 Expression exception,
61 final Expression exceptionCondition, final Block body, final boolean isSyntheticRethrow) {
62 super(lineNumber, token, finish);
63 if (exception instanceof IdentNode) {
64 this.exception = ((IdentNode) exception == null) ? null : ((IdentNode) exception).setIsInitializedHere();
65 } else {
66 this.exception = exception;
67 }
68
69 this.exceptionCondition = exceptionCondition;
70 this.body = body;
71 this.isSyntheticRethrow = isSyntheticRethrow;
72 }
73
74 private CatchNode(final CatchNode catchNode, final Expression exception, final Expression exceptionCondition,
75 final Block body, final boolean isSyntheticRethrow) {
76 super(catchNode);
77 this.exception = exception;
78 this.exceptionCondition = exceptionCondition;
79 this.body = body;
80 this.isSyntheticRethrow = isSyntheticRethrow;
81 }
82
83 /**
84 * Assist in IR navigation.
85 * @param visitor IR navigating visitor.
86 */
87 @Override
88 public Node accept(final NodeVisitor<? extends LexicalContext> visitor) {
89 if (visitor.enterCatchNode(this)) {
90 return visitor.leaveCatchNode(
91 setException((Expression) exception.accept(visitor)).
92 setExceptionCondition(exceptionCondition == null ? null : (Expression) exceptionCondition.accept(visitor)).
93 setBody((Block) body.accept(visitor)));
94 }
95 return this;
96 }
97
98 @Override
99 public boolean isTerminal() {
100 return body.isTerminal();
101 }
102
103 @Override
104 public void toString(final StringBuilder sb, final boolean printTypes) {
105 sb.append(" catch (");
106 exception.toString(sb, printTypes);
107
108 if (exceptionCondition != null) {
109 sb.append(" if ");
110 exceptionCondition.toString(sb, printTypes);
111 }
112 sb.append(')');
113 }
114
115 /**
116 * Get the identifier representing the exception thrown
117 * @return the exception identifier
118 */
119 public IdentNode getException() {
120 //Fixme :http://www.ecma-international.org/ecma-262/6.0/
121 //for now, only parsing is supported
122 if (exception instanceof IdentNode) {
123 return (IdentNode) exception;
124 } else {
125 return null;
126 }
127 }
128
129 /**
130 * Get the exception condition for this catch block
131 * @return the exception condition
132 */
133 public Expression getExceptionCondition() {
134 return exceptionCondition;
135 }
136
137 /**
138 * Reset the exception condition for this catch block
139 * @param exceptionCondition the new exception condition
140 * @return new or same CatchNode
141 */
142 public CatchNode setExceptionCondition(final Expression exceptionCondition) {
143 if (this.exceptionCondition == exceptionCondition) {
144 return this;
145 }
146 return new CatchNode(this, exception, exceptionCondition, body, isSyntheticRethrow);
147 }
148
149 /**
150 * Get the body for this catch block
151 * @return the catch block body
152 */
153 public Block getBody() {
154 return body;
155 }
156
157 /**
158 * Resets the exception of a catch block
159 * @param exception new exception
160 * @return new catch node if changed, same otherwise
161 */
162 public CatchNode setException(final Expression exception) {
163 if (this.exception == exception) {
164 return this;
165 }
166 return new CatchNode(this, exception, exceptionCondition, body, isSyntheticRethrow);
167 }
168
169 private CatchNode setBody(final Block body) {
170 if (this.body == body) {
171 return this;
172 }
173 return new CatchNode(this, exception, exceptionCondition, body, isSyntheticRethrow);
174 }
175
176 /**
177 * Is this catch block a non-JavaScript constructor, for example created as
178 * part of the rethrow mechanism of a finally block in Lower? Then we just
179 * pass the exception on and need not unwrap whatever is in the ECMAException
180 * object catch symbol
181 * @return true if a finally synthetic rethrow
182 */
183 public boolean isSyntheticRethrow() {
184 return isSyntheticRethrow;
185 }
186 }