| 1 | /******************************************************************************* |
|---|---|
| 2 | * Copyright (c) 2000, 2013 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 | * |
| 11 | * Contributors: |
| 12 | * IBM Corporation - initial API and implementation |
| 13 | *******************************************************************************/ |
| 14 | |
| 15 | package org.eclipse.jdt.core.dom; |
| 16 | |
| 17 | import java.util.ArrayList; |
| 18 | import java.util.HashMap; |
| 19 | import java.util.List; |
| 20 | import java.util.Map; |
| 21 | |
| 22 | /** |
| 23 | * Prefix expression AST node type. |
| 24 | * |
| 25 | * <pre> |
| 26 | * PrefixExpression: |
| 27 | * PrefixOperator Expression |
| 28 | * </pre> |
| 29 | * |
| 30 | * @since 2.0 |
| 31 | * @noinstantiate This class is not intended to be instantiated by clients. |
| 32 | */ |
| 33 | @SuppressWarnings({"rawtypes", "unchecked"}) |
| 34 | public class PrefixExpression extends Expression { |
| 35 | |
| 36 | /** |
| 37 | * Prefix operators (typesafe enumeration). |
| 38 | * <pre> |
| 39 | * PrefixOperator: |
| 40 | * <b><code>++</code></b> <code>INCREMENT</code> |
| 41 | * <b><code>--</code></b> <code>DECREMENT</code> |
| 42 | * <b><code>+</code></b> <code>PLUS</code> |
| 43 | * <b><code>-</code></b> <code>MINUS</code> |
| 44 | * <b><code>~</code></b> <code>COMPLEMENT</code> |
| 45 | * <b><code>!</code></b> <code>NOT</code> |
| 46 | * </pre> |
| 47 | */ |
| 48 | public static class Operator { |
| 49 | |
| 50 | /** |
| 51 | * The token for the operator. |
| 52 | */ |
| 53 | private String token; |
| 54 | |
| 55 | /** |
| 56 | * Creates a new prefix operator with the given token. |
| 57 | * <p> |
| 58 | * Note: this constructor is private. The only instances |
| 59 | * ever created are the ones for the standard operators. |
| 60 | * </p> |
| 61 | * |
| 62 | * @param token the character sequence for the operator |
| 63 | */ |
| 64 | private Operator(String token) { |
| 65 | this.token = token; |
| 66 | } |
| 67 | |
| 68 | /** |
| 69 | * Returns the character sequence for the operator. |
| 70 | * |
| 71 | * @return the character sequence for the operator |
| 72 | */ |
| 73 | @Override |
| 74 | public String toString() { |
| 75 | return this.token; |
| 76 | } |
| 77 | |
| 78 | /** Prefix increment "++" operator. */ |
| 79 | public static final Operator INCREMENT = new Operator("++");//$NON-NLS-1$ |
| 80 | /** Prefix decrement "--" operator. */ |
| 81 | public static final Operator DECREMENT = new Operator("--");//$NON-NLS-1$ |
| 82 | /** Unary plus "+" operator. */ |
| 83 | public static final Operator PLUS = new Operator("+");//$NON-NLS-1$ |
| 84 | /** Unary minus "-" operator. */ |
| 85 | public static final Operator MINUS = new Operator("-");//$NON-NLS-1$ |
| 86 | /** Bitwise complement "~" operator. */ |
| 87 | public static final Operator COMPLEMENT = new Operator("~");//$NON-NLS-1$ |
| 88 | /** Logical complement "!" operator. */ |
| 89 | public static final Operator NOT = new Operator("!");//$NON-NLS-1$ |
| 90 | |
| 91 | /** |
| 92 | * Map from token to operator (key type: <code>String</code>; |
| 93 | * value type: <code>Operator</code>). |
| 94 | */ |
| 95 | private static final Map CODES; |
| 96 | static { |
| 97 | CODES = new HashMap(20); |
| 98 | Operator[] ops = { |
| 99 | INCREMENT, |
| 100 | DECREMENT, |
| 101 | PLUS, |
| 102 | MINUS, |
| 103 | COMPLEMENT, |
| 104 | NOT, |
| 105 | }; |
| 106 | for (int i = 0; i < ops.length; i++) { |
| 107 | CODES.put(ops[i].toString(), ops[i]); |
| 108 | } |
| 109 | } |
| 110 | |
| 111 | /** |
| 112 | * Returns the prefix operator corresponding to the given string, |
| 113 | * or <code>null</code> if none. |
| 114 | * <p> |
| 115 | * <code>toOperator</code> is the converse of <code>toString</code>: |
| 116 | * that is, <code>Operator.toOperator(op.toString()) == op</code> for |
| 117 | * all operators <code>op</code>. |
| 118 | * </p> |
| 119 | * |
| 120 | * @param token the character sequence for the operator |
| 121 | * @return the prefix operator, or <code>null</code> if none |
| 122 | */ |
| 123 | public static Operator toOperator(String token) { |
| 124 | return (Operator) CODES.get(token); |
| 125 | } |
| 126 | } |
| 127 | |
| 128 | /** |
| 129 | * The "operator" structural property of this node type (type: {@link PrefixExpression.Operator}). |
| 130 | * @since 3.0 |
| 131 | */ |
| 132 | public static final SimplePropertyDescriptor OPERATOR_PROPERTY = |
| 133 | new SimplePropertyDescriptor(PrefixExpression.class, "operator", PrefixExpression.Operator.class, MANDATORY); //$NON-NLS-1$ |
| 134 | |
| 135 | /** |
| 136 | * The "operand" structural property of this node type (child type: {@link Expression}). |
| 137 | * @since 3.0 |
| 138 | */ |
| 139 | public static final ChildPropertyDescriptor OPERAND_PROPERTY = |
| 140 | new ChildPropertyDescriptor(PrefixExpression.class, "operand", Expression.class, MANDATORY, CYCLE_RISK); //$NON-NLS-1$ |
| 141 | |
| 142 | /** |
| 143 | * A list of property descriptors (element type: |
| 144 | * {@link StructuralPropertyDescriptor}), |
| 145 | * or null if uninitialized. |
| 146 | */ |
| 147 | private static final List PROPERTY_DESCRIPTORS; |
| 148 | |
| 149 | static { |
| 150 | List propertyList = new ArrayList(3); |
| 151 | createPropertyList(PrefixExpression.class, propertyList); |
| 152 | addProperty(OPERATOR_PROPERTY, propertyList); |
| 153 | addProperty(OPERAND_PROPERTY, propertyList); |
| 154 | PROPERTY_DESCRIPTORS = reapPropertyList(propertyList); |
| 155 | } |
| 156 | |
| 157 | /** |
| 158 | * Returns a list of structural property descriptors for this node type. |
| 159 | * Clients must not modify the result. |
| 160 | * |
| 161 | * @param apiLevel the API level; one of the |
| 162 | * <code>AST.JLS*</code> constants |
| 163 | |
| 164 | * @return a list of property descriptors (element type: |
| 165 | * {@link StructuralPropertyDescriptor}) |
| 166 | * @since 3.0 |
| 167 | */ |
| 168 | public static List propertyDescriptors(int apiLevel) { |
| 169 | return PROPERTY_DESCRIPTORS; |
| 170 | } |
| 171 | |
| 172 | /** |
| 173 | * The operator; defaults to an unspecified prefix operator. |
| 174 | */ |
| 175 | private PrefixExpression.Operator operator = |
| 176 | PrefixExpression.Operator.PLUS; |
| 177 | |
| 178 | /** |
| 179 | * The operand; lazily initialized; defaults to an unspecified, |
| 180 | * but legal, simple name. |
| 181 | */ |
| 182 | private Expression operand = null; |
| 183 | |
| 184 | /** |
| 185 | * Creates a new AST node for an prefix expression owned by the given |
| 186 | * AST. By default, the node has unspecified (but legal) operator and |
| 187 | * operand. |
| 188 | * |
| 189 | * @param ast the AST that is to own this node |
| 190 | */ |
| 191 | PrefixExpression(AST ast) { |
| 192 | super(ast); |
| 193 | } |
| 194 | |
| 195 | @Override |
| 196 | final List internalStructuralPropertiesForType(int apiLevel) { |
| 197 | return propertyDescriptors(apiLevel); |
| 198 | } |
| 199 | |
| 200 | @Override |
| 201 | final Object internalGetSetObjectProperty(SimplePropertyDescriptor property, boolean get, Object value) { |
| 202 | if (property == OPERATOR_PROPERTY) { |
| 203 | if (get) { |
| 204 | return getOperator(); |
| 205 | } else { |
| 206 | setOperator((Operator) value); |
| 207 | return null; |
| 208 | } |
| 209 | } |
| 210 | // allow default implementation to flag the error |
| 211 | return super.internalGetSetObjectProperty(property, get, value); |
| 212 | } |
| 213 | |
| 214 | @Override |
| 215 | final ASTNode internalGetSetChildProperty(ChildPropertyDescriptor property, boolean get, ASTNode child) { |
| 216 | if (property == OPERAND_PROPERTY) { |
| 217 | if (get) { |
| 218 | return getOperand(); |
| 219 | } else { |
| 220 | setOperand((Expression) child); |
| 221 | return null; |
| 222 | } |
| 223 | } |
| 224 | // allow default implementation to flag the error |
| 225 | return super.internalGetSetChildProperty(property, get, child); |
| 226 | } |
| 227 | |
| 228 | @Override |
| 229 | final int getNodeType0() { |
| 230 | return PREFIX_EXPRESSION; |
| 231 | } |
| 232 | |
| 233 | @Override |
| 234 | ASTNode clone0(AST target) { |
| 235 | PrefixExpression result = new PrefixExpression(target); |
| 236 | result.setSourceRange(getStartPosition(), getLength()); |
| 237 | result.setOperator(getOperator()); |
| 238 | result.setOperand((Expression) getOperand().clone(target)); |
| 239 | return result; |
| 240 | } |
| 241 | |
| 242 | @Override |
| 243 | final boolean subtreeMatch0(ASTMatcher matcher, Object other) { |
| 244 | // dispatch to correct overloaded match method |
| 245 | return matcher.match(this, other); |
| 246 | } |
| 247 | |
| 248 | @Override |
| 249 | void accept0(ASTVisitor visitor) { |
| 250 | boolean visitChildren = visitor.visit(this); |
| 251 | if (visitChildren) { |
| 252 | // visit children in normal left to right reading order |
| 253 | acceptChild(visitor, getOperand()); |
| 254 | } |
| 255 | visitor.endVisit(this); |
| 256 | } |
| 257 | |
| 258 | /** |
| 259 | * Returns the operator of this prefix expression. |
| 260 | * |
| 261 | * @return the operator |
| 262 | */ |
| 263 | public PrefixExpression.Operator getOperator() { |
| 264 | return this.operator; |
| 265 | } |
| 266 | |
| 267 | /** |
| 268 | * Sets the operator of this prefix expression. |
| 269 | * |
| 270 | * @param operator the operator |
| 271 | * @exception IllegalArgumentException if the argument is incorrect |
| 272 | */ |
| 273 | public void setOperator(PrefixExpression.Operator operator) { |
| 274 | if (operator == null) { |
| 275 | throw new IllegalArgumentException(); |
| 276 | } |
| 277 | preValueChange(OPERATOR_PROPERTY); |
| 278 | this.operator = operator; |
| 279 | postValueChange(OPERATOR_PROPERTY); |
| 280 | } |
| 281 | |
| 282 | /** |
| 283 | * Returns the operand of this prefix expression. |
| 284 | * |
| 285 | * @return the operand expression node |
| 286 | */ |
| 287 | public Expression getOperand() { |
| 288 | if (this.operand == null) { |
| 289 | // lazy init must be thread-safe for readers |
| 290 | synchronized (this) { |
| 291 | if (this.operand == null) { |
| 292 | preLazyInit(); |
| 293 | this.operand= new SimpleName(this.ast); |
| 294 | postLazyInit(this.operand, OPERAND_PROPERTY); |
| 295 | } |
| 296 | } |
| 297 | } |
| 298 | return this.operand; |
| 299 | } |
| 300 | |
| 301 | /** |
| 302 | * Sets the operand of this prefix expression. |
| 303 | * |
| 304 | * @param expression the operand expression node |
| 305 | * @exception IllegalArgumentException if: |
| 306 | * <ul> |
| 307 | * <li>the node belongs to a different AST</li> |
| 308 | * <li>the node already has a parent</li> |
| 309 | * <li>a cycle in would be created</li> |
| 310 | * </ul> |
| 311 | */ |
| 312 | public void setOperand(Expression expression) { |
| 313 | if (expression == null) { |
| 314 | throw new IllegalArgumentException(); |
| 315 | } |
| 316 | ASTNode oldChild = this.operand; |
| 317 | preReplaceChild(oldChild, expression, OPERAND_PROPERTY); |
| 318 | this.operand = expression; |
| 319 | postReplaceChild(oldChild, expression, OPERAND_PROPERTY); |
| 320 | } |
| 321 | |
| 322 | @Override |
| 323 | int memSize() { |
| 324 | // treat Operator as free |
| 325 | return BASE_NODE_SIZE + 2 * 4; |
| 326 | } |
| 327 | |
| 328 | @Override |
| 329 | int treeSize() { |
| 330 | return |
| 331 | memSize() |
| 332 | + (this.operand == null ? 0 : getOperand().treeSize()); |
| 333 | } |
| 334 | } |
| 335 | |
| 336 |
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