Java tutorial
/******************************************************************************* * Copyright (c) 2000, 2013 IBM Corporation and others. * * This program and the accompanying materials * are made available under the terms of the Eclipse Public License 2.0 * which accompanies this distribution, and is available at * https://www.eclipse.org/legal/epl-2.0/ * * SPDX-License-Identifier: EPL-2.0 * * Contributors: * IBM Corporation - initial API and implementation *******************************************************************************/ package org.eclipse.jdt.core.dom; import java.util.ArrayList; import java.util.Iterator; import java.util.List; /** * Local variable declaration statement AST node type. * <p> * This kind of node collects several variable declaration fragments * (<code>VariableDeclarationFragment</code>) into a statement * (<code>Statement</code>), all sharing the same modifiers and base type. * </p> * <pre> * VariableDeclarationStatement: * { ExtendedModifier } Type VariableDeclarationFragment * { <b>,</b> VariableDeclarationFragment } <b>;</b> * </pre> * <p> * Note: This type of node is a convenience of sorts. * An equivalent way to represent the same statement is to use * a <code>VariableDeclarationExpression</code> * wrapped in an <code>ExpressionStatement</code>. * </p> * * @since 2.0 * @noinstantiate This class is not intended to be instantiated by clients. */ @SuppressWarnings({ "rawtypes", "unchecked" }) public class VariableDeclarationStatement extends Statement { /** * The "modifiers" structural property of this node type (type: {@link Integer}) (JLS2 API only). * @since 3.0 * @deprecated In the JLS3 API, this property is replaced by {@link #MODIFIERS2_PROPERTY}. */ public static final SimplePropertyDescriptor MODIFIERS_PROPERTY = new SimplePropertyDescriptor( VariableDeclarationStatement.class, "modifiers", int.class, MANDATORY); //$NON-NLS-1$ /** * The "modifiers" structural property of this node type (element type: {@link IExtendedModifier}) (added in JLS3 API). * @since 3.1 */ public static final ChildListPropertyDescriptor MODIFIERS2_PROPERTY = new ChildListPropertyDescriptor( VariableDeclarationStatement.class, "modifiers", IExtendedModifier.class, CYCLE_RISK); //$NON-NLS-1$ /** * The "type" structural property of this node type (child type: {@link Type}). * @since 3.0 */ public static final ChildPropertyDescriptor TYPE_PROPERTY = new ChildPropertyDescriptor( VariableDeclarationStatement.class, "type", Type.class, MANDATORY, NO_CYCLE_RISK); //$NON-NLS-1$ /** * The "fragments" structural property of this node type (element type: {@link VariableDeclarationFragment}). * @since 3.0 */ public static final ChildListPropertyDescriptor FRAGMENTS_PROPERTY = new ChildListPropertyDescriptor( VariableDeclarationStatement.class, "fragments", VariableDeclarationFragment.class, CYCLE_RISK); //$NON-NLS-1$ /** * A list of property descriptors (element type: * {@link StructuralPropertyDescriptor}), * or null if uninitialized. * @since 3.0 */ private static final List PROPERTY_DESCRIPTORS_2_0; /** * A list of property descriptors (element type: * {@link StructuralPropertyDescriptor}), * or null if uninitialized. * @since 3.1 */ private static final List PROPERTY_DESCRIPTORS_3_0; static { List propertyList = new ArrayList(4); createPropertyList(VariableDeclarationStatement.class, propertyList); addProperty(MODIFIERS_PROPERTY, propertyList); addProperty(TYPE_PROPERTY, propertyList); addProperty(FRAGMENTS_PROPERTY, propertyList); PROPERTY_DESCRIPTORS_2_0 = reapPropertyList(propertyList); propertyList = new ArrayList(4); createPropertyList(VariableDeclarationStatement.class, propertyList); addProperty(MODIFIERS2_PROPERTY, propertyList); addProperty(TYPE_PROPERTY, propertyList); addProperty(FRAGMENTS_PROPERTY, propertyList); PROPERTY_DESCRIPTORS_3_0 = reapPropertyList(propertyList); } /** * Returns a list of structural property descriptors for this node type. * Clients must not modify the result. * * @param apiLevel the API level; one of the * <code>AST.JLS*</code> constants * @return a list of property descriptors (element type: * {@link StructuralPropertyDescriptor}) * @since 3.0 */ public static List propertyDescriptors(int apiLevel) { if (apiLevel == AST.JLS2_INTERNAL) { return PROPERTY_DESCRIPTORS_2_0; } else { return PROPERTY_DESCRIPTORS_3_0; } } /** * The extended modifiers (element type: {@link IExtendedModifier}). * Null in JLS2. Added in JLS3; defaults to an empty list * (see constructor). * @since 3.1 */ private ASTNode.NodeList modifiers = null; /** * The modifier flagss; bit-wise or of Modifier flags. * Defaults to none. Not used in JLS3. */ private int modifierFlags = Modifier.NONE; /** * The base type; lazily initialized; defaults to an unspecified, * legal type. */ private Type baseType = null; /** * The list of variable variable declaration fragments (element type: * {@link VariableDeclarationFragment}). Defaults to an empty list. */ private ASTNode.NodeList variableDeclarationFragments = new ASTNode.NodeList(FRAGMENTS_PROPERTY); /** * Creates a new unparented local variable declaration statement node owned * by the given AST. By default, the variable declaration has: no modifiers, * an unspecified (but legal) type, and an empty list of variable * declaration fragments (which is syntactically illegal). * <p> * N.B. This constructor is package-private. * </p> * * @param ast the AST that is to own this node */ VariableDeclarationStatement(AST ast) { super(ast); if (ast.apiLevel >= AST.JLS3_INTERNAL) { this.modifiers = new ASTNode.NodeList(MODIFIERS2_PROPERTY); } } @Override final List internalStructuralPropertiesForType(int apiLevel) { return propertyDescriptors(apiLevel); } @Override final int internalGetSetIntProperty(SimplePropertyDescriptor property, boolean get, int value) { if (property == MODIFIERS_PROPERTY) { if (get) { return getModifiers(); } else { setModifiers(value); return 0; } } // allow default implementation to flag the error return super.internalGetSetIntProperty(property, get, value); } @Override final ASTNode internalGetSetChildProperty(ChildPropertyDescriptor property, boolean get, ASTNode child) { if (property == TYPE_PROPERTY) { if (get) { return getType(); } else { setType((Type) child); return null; } } // allow default implementation to flag the error return super.internalGetSetChildProperty(property, get, child); } @Override final List internalGetChildListProperty(ChildListPropertyDescriptor property) { if (property == MODIFIERS2_PROPERTY) { return modifiers(); } if (property == FRAGMENTS_PROPERTY) { return fragments(); } // allow default implementation to flag the error return super.internalGetChildListProperty(property); } @Override final int getNodeType0() { return VARIABLE_DECLARATION_STATEMENT; } @Override ASTNode clone0(AST target) { VariableDeclarationStatement result = new VariableDeclarationStatement(target); result.setSourceRange(getStartPosition(), getLength()); result.copyLeadingComment(this); if (this.ast.apiLevel == AST.JLS2_INTERNAL) { result.setModifiers(getModifiers()); } if (this.ast.apiLevel >= AST.JLS3_INTERNAL) { result.modifiers().addAll(ASTNode.copySubtrees(target, modifiers())); } result.setType((Type) getType().clone(target)); result.fragments().addAll(ASTNode.copySubtrees(target, fragments())); return result; } @Override final boolean subtreeMatch0(ASTMatcher matcher, Object other) { // dispatch to correct overloaded match method return matcher.match(this, other); } @Override void accept0(ASTVisitor visitor) { boolean visitChildren = visitor.visit(this); if (visitChildren) { // visit children in normal left to right reading order if (this.ast.apiLevel >= AST.JLS3_INTERNAL) { acceptChildren(visitor, this.modifiers); } acceptChild(visitor, getType()); acceptChildren(visitor, this.variableDeclarationFragments); } visitor.endVisit(this); } /** * Returns the live ordered list of modifiers and annotations * of this declaration (added in JLS3 API). * <p> * Note that the final modifier is the only meaningful modifier for local * variable declarations. * </p> * * @return the live list of modifiers and annotations * (element type: {@link IExtendedModifier}) * @exception UnsupportedOperationException if this operation is used in * a JLS2 AST * @since 3.1 */ public List modifiers() { // more efficient than just calling unsupportedIn2() to check if (this.modifiers == null) { unsupportedIn2(); } return this.modifiers; } /** * Returns the modifiers explicitly specified on this declaration. * <p> * In the JLS3 API, this method is a convenience method that * computes these flags from <code>modifiers()</code>. * </p> * * @return the bit-wise or of <code>Modifier</code> constants * @see Modifier */ public int getModifiers() { // more efficient than checking getAST().API_LEVEL if (this.modifiers == null) { // JLS2 behavior - bona fide property return this.modifierFlags; } else { // JLS3 behavior - convenience method // performance could be improved by caching computed flags // but this would require tracking changes to this.modifiers int computedModifierFlags = Modifier.NONE; for (Iterator it = modifiers().iterator(); it.hasNext();) { Object x = it.next(); if (x instanceof Modifier) { computedModifierFlags |= ((Modifier) x).getKeyword().toFlagValue(); } } return computedModifierFlags; } } /** * Sets the modifiers explicitly specified on this declaration (JLS2 API only). * <p> * Note that the final modifier is the only meaningful modifier for local * variable declarations. * </p> * * @param modifiers the given modifiers (bit-wise or of <code>Modifier</code> constants) * @exception UnsupportedOperationException if this operation is used in * an AST later than JLS2 * @see Modifier * @deprecated In the JLS3 API, this method is replaced by * {@link #modifiers()} which contains a list of a <code>Modifier</code> nodes. */ public void setModifiers(int modifiers) { internalSetModifiers(modifiers); } /** * Internal synonym for deprecated method. Used to avoid * deprecation warnings. * @since 3.1 */ /*package*/ final void internalSetModifiers(int pmodifiers) { supportedOnlyIn2(); preValueChange(MODIFIERS_PROPERTY); this.modifierFlags = pmodifiers; postValueChange(MODIFIERS_PROPERTY); } /** * Returns the base type declared in this variable declaration statement. * <p> * N.B. The individual child variable declaration fragments may specify * additional array dimensions. So the type of the variable are not * necessarily exactly this type. * </p> * * @return the base type */ public Type getType() { if (this.baseType == null) { // lazy init must be thread-safe for readers synchronized (this) { if (this.baseType == null) { preLazyInit(); this.baseType = this.ast.newPrimitiveType(PrimitiveType.INT); postLazyInit(this.baseType, TYPE_PROPERTY); } } } return this.baseType; } /** * Sets the base type declared in this variable declaration statement to * the given type. * * @param type the new base type * @exception IllegalArgumentException if: * <ul> * <li>the node belongs to a different AST</li> * <li>the node already has a parent</li> * </ul> */ public void setType(Type type) { if (type == null) { throw new IllegalArgumentException(); } ASTNode oldChild = this.baseType; preReplaceChild(oldChild, type, TYPE_PROPERTY); this.baseType = type; postReplaceChild(oldChild, type, TYPE_PROPERTY); } /** * Returns the live list of variable declaration fragments in this statement. * Adding and removing nodes from this list affects this node dynamically. * All nodes in this list must be <code>VariableDeclarationFragment</code>s; * attempts to add any other type of node will trigger an * exception. * * @return the live list of variable declaration fragments in this * statement (element type: {@link VariableDeclarationFragment}) */ public List fragments() { return this.variableDeclarationFragments; } @Override int memSize() { return super.memSize() + 4 * 4; } @Override int treeSize() { return memSize() + (this.modifiers == null ? 0 : this.modifiers.listSize()) + (this.baseType == null ? 0 : getType().treeSize()) + this.variableDeclarationFragments.listSize(); } }