| 1 | /******************************************************************************* |
|---|---|
| 2 | * Copyright (c) 2000, 2021 IBM Corporation and others. |
| 3 | * |
| 4 | * This program and the accompanying materials |
| 5 | * are made available under the terms of the Eclipse Public License 2.0 |
| 6 | * which accompanies this distribution, and is available at |
| 7 | * https://www.eclipse.org/legal/epl-2.0/ |
| 8 | * |
| 9 | * SPDX-License-Identifier: EPL-2.0 |
| 10 | * Contributors: |
| 11 | * IBM Corporation - initial API and implementation |
| 12 | *******************************************************************************/ |
| 13 | |
| 14 | package org.eclipse.jdt.core.dom; |
| 15 | |
| 16 | import java.util.ArrayList; |
| 17 | import java.util.List; |
| 18 | |
| 19 | /** |
| 20 | * Switch case AST node type. A switch case is a special kind of node used only |
| 21 | * in switch statements. It is a <code>Statement</code> in name only. |
| 22 | * <pre> |
| 23 | * SwitchCase: |
| 24 | * <b>case</b> Expression <b>:</b> |
| 25 | * <b>default</b> <b>:</b> |
| 26 | * |
| 27 | * Switch case allows multiple expressions and '->' as part of Java 12 preview feature (JEP 325) |
| 28 | * <b>case</b> [ Expression { <b>,</b> Expression } ] <b>{ : | ->}</b> |
| 29 | * <b>default</b> <b>{ : | ->}</b> |
| 30 | * </pre> |
| 31 | * |
| 32 | * @since 2.0 |
| 33 | * @noinstantiate This class is not intended to be instantiated by clients. |
| 34 | */ |
| 35 | @SuppressWarnings("rawtypes") |
| 36 | public class SwitchCase extends Statement { |
| 37 | |
| 38 | /** |
| 39 | * The "expression" structural property of this node type (child type: {@link Expression}). |
| 40 | * @since 3.0 |
| 41 | * @deprecated In the JLS 12 15.28.1 API, this property is replaced by {@link #EXPRESSIONS2_PROPERTY }. |
| 42 | */ |
| 43 | public static final ChildPropertyDescriptor EXPRESSION_PROPERTY = |
| 44 | new ChildPropertyDescriptor(SwitchCase.class, "expression", Expression.class, OPTIONAL, CYCLE_RISK); //$NON-NLS-1$ |
| 45 | |
| 46 | /** |
| 47 | * The "expression" structural property of this node type (child type: {@link Expression}). (added in JEP 325). |
| 48 | * @since 3.18 |
| 49 | */ |
| 50 | public static final ChildListPropertyDescriptor EXPRESSIONS2_PROPERTY = |
| 51 | new ChildListPropertyDescriptor(SwitchCase.class, "expression", Expression.class, CYCLE_RISK); //$NON-NLS-1$); |
| 52 | |
| 53 | /** |
| 54 | * The "switchLabeledRule" structural property of this node type (type: {@link Boolean}). |
| 55 | * @since 3.18 |
| 56 | */ |
| 57 | public static final SimplePropertyDescriptor SWITCH_LABELED_RULE_PROPERTY = |
| 58 | new SimplePropertyDescriptor(SwitchCase.class, "switchLabeledRule", boolean.class, MANDATORY); //$NON-NLS-1$ |
| 59 | |
| 60 | /** |
| 61 | * A list of property descriptors (element type: |
| 62 | * {@link StructuralPropertyDescriptor}), |
| 63 | * or null if uninitialized. |
| 64 | */ |
| 65 | private static final List PROPERTY_DESCRIPTORS; |
| 66 | |
| 67 | /** |
| 68 | * A list of property descriptors (element type: |
| 69 | * {@link StructuralPropertyDescriptor}), |
| 70 | * or null if uninitialized. |
| 71 | */ |
| 72 | private static final List PROPERTY_DESCRIPTORS_13; |
| 73 | |
| 74 | static { |
| 75 | List propertyList = new ArrayList(2); |
| 76 | createPropertyList(SwitchCase.class, propertyList); |
| 77 | addProperty(EXPRESSION_PROPERTY, propertyList); |
| 78 | PROPERTY_DESCRIPTORS = reapPropertyList(propertyList); |
| 79 | |
| 80 | propertyList = new ArrayList(2); |
| 81 | createPropertyList(SwitchCase.class, propertyList); |
| 82 | addProperty(EXPRESSIONS2_PROPERTY , propertyList); |
| 83 | addProperty(SWITCH_LABELED_RULE_PROPERTY, propertyList); |
| 84 | PROPERTY_DESCRIPTORS_13 = reapPropertyList(propertyList); |
| 85 | } |
| 86 | |
| 87 | /** |
| 88 | * Returns a list of structural property descriptors for this node type. |
| 89 | * Clients must not modify the result. |
| 90 | * |
| 91 | * @param apiLevel the API level; one of the |
| 92 | * <code>AST.JLS*</code> constants |
| 93 | * @return a list of property descriptors (element type: |
| 94 | * {@link StructuralPropertyDescriptor}) |
| 95 | * @since 3.0 |
| 96 | */ |
| 97 | public static List propertyDescriptors(int apiLevel) { |
| 98 | if (apiLevel >= AST.JLS14_INTERNAL) { |
| 99 | return PROPERTY_DESCRIPTORS_13; |
| 100 | } |
| 101 | return PROPERTY_DESCRIPTORS; |
| 102 | } |
| 103 | |
| 104 | /** |
| 105 | * The expression; <code>null</code> for none; lazily initialized (but |
| 106 | * does <b>not</b> default to none). |
| 107 | * @see #expressionInitialized |
| 108 | */ |
| 109 | private Expression optionalExpression = null; |
| 110 | |
| 111 | /** |
| 112 | * <code>true</code> indicates "->" and <code>false</code> indicates ":". |
| 113 | */ |
| 114 | private boolean switchLabeledRule = false; |
| 115 | |
| 116 | |
| 117 | /** |
| 118 | * The expression list; <code>empty</code> for none; |
| 119 | */ |
| 120 | private ASTNode.NodeList expressions = null; |
| 121 | |
| 122 | /** |
| 123 | * Indicates whether <code>optionalExpression</code> has been initialized. |
| 124 | */ |
| 125 | private boolean expressionInitialized = false; |
| 126 | |
| 127 | /** |
| 128 | * Creates a new AST node for a switch case pseudo-statement owned by the |
| 129 | * given AST. By default, there is no expression, but legal, and switchLabeledRule |
| 130 | * is false which indicates ":". |
| 131 | * |
| 132 | * @param ast the AST that is to own this node |
| 133 | */ |
| 134 | SwitchCase(AST ast) { |
| 135 | super(ast); |
| 136 | if (ast.apiLevel >= AST.JLS14_INTERNAL) { |
| 137 | this.expressions = new ASTNode.NodeList(EXPRESSIONS2_PROPERTY ); |
| 138 | } |
| 139 | } |
| 140 | |
| 141 | @Override |
| 142 | final List internalStructuralPropertiesForType(int apiLevel) { |
| 143 | return propertyDescriptors(apiLevel); |
| 144 | } |
| 145 | |
| 146 | @Override |
| 147 | final boolean internalGetSetBooleanProperty(SimplePropertyDescriptor property, boolean get, boolean value) { |
| 148 | if (property == SWITCH_LABELED_RULE_PROPERTY) { |
| 149 | if (get) { |
| 150 | return isSwitchLabeledRule(); |
| 151 | } else { |
| 152 | setSwitchLabeledRule(value); |
| 153 | return false; |
| 154 | } |
| 155 | } |
| 156 | // allow default implementation to flag the error |
| 157 | return super.internalGetSetBooleanProperty(property, get, value); |
| 158 | } |
| 159 | |
| 160 | @Override |
| 161 | final ASTNode internalGetSetChildProperty(ChildPropertyDescriptor property, boolean get, ASTNode child) { |
| 162 | if (property == EXPRESSION_PROPERTY) { |
| 163 | if (get) { |
| 164 | return getExpression(); |
| 165 | } else { |
| 166 | setExpression((Expression) child); |
| 167 | return null; |
| 168 | } |
| 169 | } |
| 170 | // allow default implementation to flag the error |
| 171 | return super.internalGetSetChildProperty(property, get, child); |
| 172 | } |
| 173 | |
| 174 | @Override |
| 175 | final List internalGetChildListProperty(ChildListPropertyDescriptor property) { |
| 176 | if (property == EXPRESSIONS2_PROPERTY ) { |
| 177 | return expressions(); |
| 178 | } |
| 179 | // allow default implementation to flag the error |
| 180 | return super.internalGetChildListProperty(property); |
| 181 | } |
| 182 | |
| 183 | @Override |
| 184 | final int getNodeType0() { |
| 185 | return SWITCH_CASE; |
| 186 | } |
| 187 | |
| 188 | @SuppressWarnings("unchecked") |
| 189 | @Override |
| 190 | ASTNode clone0(AST target) { |
| 191 | SwitchCase result = new SwitchCase(target); |
| 192 | result.setSourceRange(getStartPosition(), getLength()); |
| 193 | result.copyLeadingComment(this); |
| 194 | if (this.ast.apiLevel >= AST.JLS14_INTERNAL) { |
| 195 | result.expressions().addAll( |
| 196 | ASTNode.copySubtrees(target, expressions())); |
| 197 | } else { |
| 198 | result.setExpression( |
| 199 | (Expression) ASTNode.copySubtree(target, getExpression())); |
| 200 | } |
| 201 | return result; |
| 202 | } |
| 203 | |
| 204 | @Override |
| 205 | final boolean subtreeMatch0(ASTMatcher matcher, Object other) { |
| 206 | // dispatch to correct overloaded match method |
| 207 | return matcher.match(this, other); |
| 208 | } |
| 209 | |
| 210 | @Override |
| 211 | void accept0(ASTVisitor visitor) { |
| 212 | boolean visitChildren = visitor.visit(this); |
| 213 | if (visitChildren) { |
| 214 | if (this.ast.apiLevel >= AST.JLS14_INTERNAL) { |
| 215 | acceptChildren(visitor, this.expressions); |
| 216 | } else { |
| 217 | acceptChild(visitor, getExpression()); |
| 218 | } |
| 219 | } |
| 220 | visitor.endVisit(this); |
| 221 | } |
| 222 | |
| 223 | /** |
| 224 | * Returns the expression of this switch case, or |
| 225 | * <code>null</code> if there is none (the "default:" case). |
| 226 | * |
| 227 | * @return the expression node, or <code>null</code> if there is none |
| 228 | * @deprecated use expressions() (see JLS 12) |
| 229 | */ |
| 230 | public Expression getExpression() { |
| 231 | if (!this.expressionInitialized) { |
| 232 | // lazy init must be thread-safe for readers |
| 233 | synchronized (this) { |
| 234 | if (!this.expressionInitialized) { |
| 235 | preLazyInit(); |
| 236 | this.optionalExpression = new SimpleName(this.ast); |
| 237 | this.expressionInitialized = true; |
| 238 | postLazyInit(this.optionalExpression, EXPRESSION_PROPERTY); |
| 239 | } |
| 240 | } |
| 241 | } |
| 242 | return this.optionalExpression; |
| 243 | } |
| 244 | |
| 245 | /** |
| 246 | * Returns the list of expressions of this switch case, or |
| 247 | * <code>empty</code> if there is none (the "default:" case). |
| 248 | * |
| 249 | * @return the list of expression nodes |
| 250 | * (element type: {@link Expression}) |
| 251 | * @exception UnsupportedOperationException if this operation is used below JLS14 |
| 252 | * @since 3.22 |
| 253 | */ |
| 254 | public List expressions() { |
| 255 | if (this.expressions == null) { |
| 256 | unsupportedBelow14(); |
| 257 | } |
| 258 | return this.expressions; |
| 259 | } |
| 260 | |
| 261 | /** |
| 262 | * Sets the expression of this switch case, or clears it (turns it into |
| 263 | * the "default:" case). |
| 264 | * |
| 265 | * @param expression the expression node, or <code>null</code> to |
| 266 | * turn it into the "default:" case |
| 267 | * @exception IllegalArgumentException if: |
| 268 | * <ul> |
| 269 | * <li>the node belongs to a different AST</li> |
| 270 | * <li>the node already has a parent</li> |
| 271 | * <li>a cycle in would be created</li> |
| 272 | * </ul> |
| 273 | * @deprecated see JLS 12 |
| 274 | */ |
| 275 | public void setExpression(Expression expression) { |
| 276 | ASTNode oldChild = this.optionalExpression; |
| 277 | preReplaceChild(oldChild, expression, EXPRESSION_PROPERTY); |
| 278 | this.optionalExpression = expression; |
| 279 | this.expressionInitialized = true; |
| 280 | postReplaceChild(oldChild, expression, EXPRESSION_PROPERTY); |
| 281 | } |
| 282 | |
| 283 | /** |
| 284 | * Sets the switchLabeledRule of this switch case as <code>true</code> or <code>false</code>. |
| 285 | * <code>true</code> indicates "->" and <code>false</code> indicates ":". |
| 286 | |
| 287 | * @param switchLabeledRule <code>true</code> or <code>false</code> |
| 288 | * @exception UnsupportedOperationException if this operation is used below JLS14 |
| 289 | * @since 3.22 |
| 290 | */ |
| 291 | public void setSwitchLabeledRule(boolean switchLabeledRule) { |
| 292 | unsupportedBelow14(); |
| 293 | preValueChange(SWITCH_LABELED_RULE_PROPERTY); |
| 294 | this.switchLabeledRule = switchLabeledRule; |
| 295 | postValueChange(SWITCH_LABELED_RULE_PROPERTY); |
| 296 | } |
| 297 | |
| 298 | /** |
| 299 | * Gets the switchLabeledRule of this switch case as <code>true</code> or <code>false</code>. |
| 300 | *<code>true</code> indicates "->" and <code>false</code> indicates ":". |
| 301 | * |
| 302 | * @return switchLabeledRule <code>true</code> or <code>false</code> |
| 303 | * @exception UnsupportedOperationException if this operation is used below JLS14 |
| 304 | * @since 3.22 |
| 305 | */ |
| 306 | public boolean isSwitchLabeledRule() { |
| 307 | unsupportedBelow14(); |
| 308 | return this.switchLabeledRule; |
| 309 | } |
| 310 | |
| 311 | /** |
| 312 | * Returns whether this switch case represents the "default:" case. |
| 313 | * <p> |
| 314 | * This convenience method is equivalent to |
| 315 | * <code>getExpression() == null</code> or <code>expressions().isEmpty()</code>. |
| 316 | * </p> |
| 317 | * |
| 318 | * @return <code>true</code> if this is the default switch case, and |
| 319 | * <code>false</code> if this is a non-default switch case |
| 320 | */ |
| 321 | public boolean isDefault() { |
| 322 | if (this.ast.apiLevel >= AST.JLS14_INTERNAL) { |
| 323 | return expressions().isEmpty(); |
| 324 | } |
| 325 | return getExpression() == null; |
| 326 | } |
| 327 | |
| 328 | @Override |
| 329 | int memSize() { |
| 330 | return super.memSize() + 2 * 4; |
| 331 | } |
| 332 | |
| 333 | @Override |
| 334 | int treeSize() { |
| 335 | return |
| 336 | memSize() |
| 337 | + (this.optionalExpression == null ? 0 : this.optionalExpression.treeSize()); |
| 338 | } |
| 339 | |
| 340 | |
| 341 | } |
| 342 |
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