/*******************************************************************************
* Copyright (c) 2000, 2009 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.jdt.core.dom;
import java.util.AbstractList;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import org.eclipse.jdt.internal.core.dom.NaiveASTFlattener;
/**
* Abstract superclass of all Abstract Syntax Tree (AST) node types.
* <p>
* An AST node represents a Java source code construct, such as a name, type, expression, statement,
* or declaration.
* </p>
* <p>
* Each AST node belongs to a unique AST instance, called the owning AST. The children of an AST
* node always have the same owner as their parent node. If a node from one AST is to be added to a
* different AST, the subtree must be cloned first to ensure that the added nodes have the correct
* owning AST.
* </p>
* <p>
* When an AST node is part of an AST, it has a unique parent node. Clients can navigate upwards,
* from child to parent, as well as downwards, from parent to child. Newly created nodes are
* unparented. When an unparented node is set as a child of a node (using a
* <code>set<i>CHILD</i></code> method), its parent link is set automatically and the parent link of
* the former child is set to <code>null</code>. For nodes with properties that include a list of
* children (for example, <code>Block</code> whose <code>statements</code> property is a list of
* statements), adding or removing an element to/for the list property automatically updates the
* parent links. These lists support the <code>List.set</code> method; however, the constraint that
* the same node cannot appear more than once means that this method cannot be used to swap elements
* without first removing the node.
* </p>
* <p>
* ASTs must not contain cycles. All operations that could create a cycle detect this possibility
* and fail.
* </p>
* <p>
* ASTs do not contain "holes" (missing subtrees). If a node is required to have a certain property,
* a syntactically plausible initial value is always supplied.
* </p>
* <p>
* The hierarchy of AST node types has some convenient groupings marked by abstract superclasses:
* <ul>
* <li>expressions - <code>Expression</code></li>
* <li>names - <code>Name</code> (a sub-kind of expression)</li>
* <li>statements - <code>Statement</code></li>
* <li>types - <code>Type</code></li>
* <li>type body declarations - <code>BodyDeclaration</code></li>
* </ul>
* </p>
* <p>
* Abstract syntax trees may be hand constructed by clients, using the <code>new<i>TYPE</i></code>
* factory methods (see <code>AST</code>) to create new nodes, and the various
* <code>set<i>CHILD</i></code> methods to connect them together.
* </p>
* <p>
* The class {@link ASTParser} parses a string containing a Java source code and returns an abstract
* syntax tree for it. The resulting nodes carry source ranges relating the node back to the
* original source characters. The source range covers the construct as a whole.
* </p>
* <p>
* Each AST node carries bit flags, which may convey additional information about the node. For
* instance, the parser uses a flag to indicate a syntax error. Newly created nodes have no flags
* set.
* </p>
* <p>
* Each AST node is capable of carrying an open-ended collection of client-defined properties. Newly
* created nodes have none. <code>getProperty</code> and <code>setProperty</code> are used to access
* these properties.
* </p>
* <p>
* AST nodes are thread-safe for readers provided there are no active writers. If one thread is
* modifying an AST, including creating new nodes or cloning existing ones, it is <b>not</b> safe
* for another thread to read, visit, write, create, or clone <em>any</em> of the nodes on the same
* AST. When synchronization is required, consider using the common AST object that owns the node;
* that is, use <code>synchronize (node.getAST()) {...}</code>.
* </p>
* <p>
* ASTs also support the visitor pattern; see the class <code>ASTVisitor</code> for details. The
* <code>NodeFinder</code> class can be used to find a specific node inside a tree.
* </p>
* <p>
* Compilation units created by <code>ASTParser</code> from a source document can be serialized
* after arbitrary modifications with minimal loss of original formatting. See
* {@link CompilationUnit#recordModifications()} for details. See also
* {@link org.eclipse.jdt.core.dom.rewrite.ASTRewrite} for an alternative way to describe and
* serialize changes to a read-only AST.
* </p>
*
* @see ASTParser
* @see ASTVisitor
* @see NodeFinder
* @since 2.0
* @noextend This class is not intended to be subclassed by clients.
*/
public abstract class ASTNode {
/*
* INSTRUCTIONS FOR ADDING NEW CONCRETE AST NODE TYPES
*
* There are several things that need to be changed when a
* new concrete AST node type (call it "FooBar"):
*
* 1. Create the FooBar AST node type class.
* The most effective way to do this is to copy a similar
* existing concrete node class to get a template that
* includes all the framework methods that must be implemented.
*
* 2. Add node type constant ASTNode.FOO_BAR.
* Node constants are numbered consecutively. Add the
* constant after the existing ones.
*
* 3. Add entry to ASTNode.nodeClassForType(int).
*
* 4. Add AST.newFooBar() factory method.
*
* 5. Add ASTVisitor.visit(FooBar) and endVisit(FooBar) methods.
*
* 6. Add ASTMatcher.match(FooBar,Object) method.
*
* 7. Ensure that SimpleName.isDeclaration() covers FooBar
* nodes if required.
*
* 8. Add NaiveASTFlattener.visit(FooBar) method to illustrate
* how these nodes should be serialized.
*
* 9. Update the AST test suites.
*
* The next steps are to update AST.parse* to start generating
* the new type of nodes, and ASTRewrite to serialize them back out.
*/
/**
* Node type constant indicating a node of type <code>AnonymousClassDeclaration</code>.
*
* @see AnonymousClassDeclaration
*/
public static final int ANONYMOUS_CLASS_DECLARATION= 1;
/**
* Node type constant indicating a node of type <code>ArrayAccess</code>.
*
* @see ArrayAccess
*/
public static final int ARRAY_ACCESS= 2;
/**
* Node type constant indicating a node of type <code>ArrayCreation</code>.
*
* @see ArrayCreation
*/
public static final int ARRAY_CREATION= 3;
/**
* Node type constant indicating a node of type <code>ArrayInitializer</code>.
*
* @see ArrayInitializer
*/
public static final int ARRAY_INITIALIZER= 4;
/**
* Node type constant indicating a node of type <code>ArrayType</code>.
*
* @see ArrayType
*/
public static final int ARRAY_TYPE= 5;
/**
* Node type constant indicating a node of type <code>AssertStatement</code>.
*
* @see AssertStatement
*/
public static final int ASSERT_STATEMENT= 6;
/**
* Node type constant indicating a node of type <code>Assignment</code>.
*
* @see Assignment
*/
public static final int ASSIGNMENT= 7;
/**
* Node type constant indicating a node of type <code>Block</code>.
*
* @see Block
*/
public static final int BLOCK= 8;
/**
* Node type constant indicating a node of type <code>BooleanLiteral</code>.
*
* @see BooleanLiteral
*/
public static final int BOOLEAN_LITERAL= 9;
/**
* Node type constant indicating a node of type <code>BreakStatement</code>.
*
* @see BreakStatement
*/
public static final int BREAK_STATEMENT= 10;
/**
* Node type constant indicating a node of type <code>CastExpression</code>.
*
* @see CastExpression
*/
public static final int CAST_EXPRESSION= 11;
/**
* Node type constant indicating a node of type <code>CatchClause</code>.
*
* @see CatchClause
*/
public static final int CATCH_CLAUSE= 12;
/**
* Node type constant indicating a node of type <code>CharacterLiteral</code>.
*
* @see CharacterLiteral
*/
public static final int CHARACTER_LITERAL= 13;
/**
* Node type constant indicating a node of type <code>ClassInstanceCreation</code>.
*
* @see ClassInstanceCreation
*/
public static final int CLASS_INSTANCE_CREATION= 14;
/**
* Node type constant indicating a node of type <code>CompilationUnit</code>.
*
* @see CompilationUnit
*/
public static final int COMPILATION_UNIT= 15;
/**
* Node type constant indicating a node of type <code>ConditionalExpression</code>.
*
* @see ConditionalExpression
*/
public static final int CONDITIONAL_EXPRESSION= 16;
/**
* Node type constant indicating a node of type <code>ConstructorInvocation</code>.
*
* @see ConstructorInvocation
*/
public static final int CONSTRUCTOR_INVOCATION= 17;
/**
* Node type constant indicating a node of type <code>ContinueStatement</code>.
*
* @see ContinueStatement
*/
public static final int CONTINUE_STATEMENT= 18;
/**
* Node type constant indicating a node of type <code>DoStatement</code>.
*
* @see DoStatement
*/
public static final int DO_STATEMENT= 19;
/**
* Node type constant indicating a node of type <code>EmptyStatement</code>.
*
* @see EmptyStatement
*/
public static final int EMPTY_STATEMENT= 20;
/**
* Node type constant indicating a node of type <code>ExpressionStatement</code>.
*
* @see ExpressionStatement
*/
public static final int EXPRESSION_STATEMENT= 21;
/**
* Node type constant indicating a node of type <code>FieldAccess</code>.
*
* @see FieldAccess
*/
public static final int FIELD_ACCESS= 22;
/**
* Node type constant indicating a node of type <code>FieldDeclaration</code>.
*
* @see FieldDeclaration
*/
public static final int FIELD_DECLARATION= 23;
/**
* Node type constant indicating a node of type <code>ForStatement</code>.
*
* @see ForStatement
*/
public static final int FOR_STATEMENT= 24;
/**
* Node type constant indicating a node of type <code>IfStatement</code>.
*
* @see IfStatement
*/
public static final int IF_STATEMENT= 25;
/**
* Node type constant indicating a node of type <code>ImportDeclaration</code>.
*
* @see ImportDeclaration
*/
public static final int IMPORT_DECLARATION= 26;
/**
* Node type constant indicating a node of type <code>InfixExpression</code>.
*
* @see InfixExpression
*/
public static final int INFIX_EXPRESSION= 27;
/**
* Node type constant indicating a node of type <code>Initializer</code>.
*
* @see Initializer
*/
public static final int INITIALIZER= 28;
/**
* Node type constant indicating a node of type <code>Javadoc</code>.
*
* @see Javadoc
*/
public static final int JAVADOC= 29;
/**
* Node type constant indicating a node of type <code>LabeledStatement</code>.
*
* @see LabeledStatement
*/
public static final int LABELED_STATEMENT= 30;
/**
* Node type constant indicating a node of type <code>MethodDeclaration</code>.
*
* @see MethodDeclaration
*/
public static final int METHOD_DECLARATION= 31;
/**
* Node type constant indicating a node of type <code>MethodInvocation</code>.
*
* @see MethodInvocation
*/
public static final int METHOD_INVOCATION= 32;
/**
* Node type constant indicating a node of type <code>NullLiteral</code>.
*
* @see NullLiteral
*/
public static final int NULL_LITERAL= 33;
/**
* Node type constant indicating a node of type <code>NumberLiteral</code>.
*
* @see NumberLiteral
*/
public static final int NUMBER_LITERAL= 34;
/**
* Node type constant indicating a node of type <code>PackageDeclaration</code>.
*
* @see PackageDeclaration
*/
public static final int PACKAGE_DECLARATION= 35;
/**
* Node type constant indicating a node of type <code>ParenthesizedExpression</code>.
*
* @see ParenthesizedExpression
*/
public static final int PARENTHESIZED_EXPRESSION= 36;
/**
* Node type constant indicating a node of type <code>PostfixExpression</code>.
*
* @see PostfixExpression
*/
public static final int POSTFIX_EXPRESSION= 37;
/**
* Node type constant indicating a node of type <code>PrefixExpression</code>.
*
* @see PrefixExpression
*/
public static final int PREFIX_EXPRESSION= 38;
/**
* Node type constant indicating a node of type <code>PrimitiveType</code>.
*
* @see PrimitiveType
*/
public static final int PRIMITIVE_TYPE= 39;
/**
* Node type constant indicating a node of type <code>QualifiedName</code>.
*
* @see QualifiedName
*/
public static final int QUALIFIED_NAME= 40;
/**
* Node type constant indicating a node of type <code>ReturnStatement</code>.
*
* @see ReturnStatement
*/
public static final int RETURN_STATEMENT= 41;
/**
* Node type constant indicating a node of type <code>SimpleName</code>.
*
* @see SimpleName
*/
public static final int SIMPLE_NAME= 42;
/**
* Node type constant indicating a node of type <code>SimpleType</code>.
*
* @see SimpleType
*/
public static final int SIMPLE_TYPE= 43;
/**
* Node type constant indicating a node of type <code>SingleVariableDeclaration</code>.
*
* @see SingleVariableDeclaration
*/
public static final int SINGLE_VARIABLE_DECLARATION= 44;
/**
* Node type constant indicating a node of type <code>StringLiteral</code>.
*
* @see StringLiteral
*/
public static final int STRING_LITERAL= 45;
/**
* Node type constant indicating a node of type <code>SuperConstructorInvocation</code>.
*
* @see SuperConstructorInvocation
*/
public static final int SUPER_CONSTRUCTOR_INVOCATION= 46;
/**
* Node type constant indicating a node of type <code>SuperFieldAccess</code>.
*
* @see SuperFieldAccess
*/
public static final int SUPER_FIELD_ACCESS= 47;
/**
* Node type constant indicating a node of type <code>SuperMethodInvocation</code>.
*
* @see SuperMethodInvocation
*/
public static final int SUPER_METHOD_INVOCATION= 48;
/**
* Node type constant indicating a node of type <code>SwitchCase</code>.
*
* @see SwitchCase
*/
public static final int SWITCH_CASE= 49;
/**
* Node type constant indicating a node of type <code>SwitchStatement</code>.
*
* @see SwitchStatement
*/
public static final int SWITCH_STATEMENT= 50;
/**
* Node type constant indicating a node of type <code>SynchronizedStatement</code>.
*
* @see SynchronizedStatement
*/
public static final int SYNCHRONIZED_STATEMENT= 51;
/**
* Node type constant indicating a node of type <code>ThisExpression</code>.
*
* @see ThisExpression
*/
public static final int THIS_EXPRESSION= 52;
/**
* Node type constant indicating a node of type <code>ThrowStatement</code>.
*
* @see ThrowStatement
*/
public static final int THROW_STATEMENT= 53;
/**
* Node type constant indicating a node of type <code>TryStatement</code>.
*
* @see TryStatement
*/
public static final int TRY_STATEMENT= 54;
/**
* Node type constant indicating a node of type <code>TypeDeclaration</code>.
*
* @see TypeDeclaration
*/
public static final int TYPE_DECLARATION= 55;
/**
* Node type constant indicating a node of type <code>TypeDeclarationStatement</code>.
*
* @see TypeDeclarationStatement
*/
public static final int TYPE_DECLARATION_STATEMENT= 56;
/**
* Node type constant indicating a node of type <code>TypeLiteral</code>.
*
* @see TypeLiteral
*/
public static final int TYPE_LITERAL= 57;
/**
* Node type constant indicating a node of type <code>VariableDeclarationExpression</code>.
*
* @see VariableDeclarationExpression
*/
public static final int VARIABLE_DECLARATION_EXPRESSION= 58;
/**
* Node type constant indicating a node of type <code>VariableDeclarationFragment</code>.
*
* @see VariableDeclarationFragment
*/
public static final int VARIABLE_DECLARATION_FRAGMENT= 59;
/**
* Node type constant indicating a node of type <code>VariableDeclarationStatement</code>.
*
* @see VariableDeclarationStatement
*/
public static final int VARIABLE_DECLARATION_STATEMENT= 60;
/**
* Node type constant indicating a node of type <code>WhileStatement</code>.
*
* @see WhileStatement
*/
public static final int WHILE_STATEMENT= 61;
/**
* Node type constant indicating a node of type <code>InstanceofExpression</code>.
*
* @see InstanceofExpression
*/
public static final int INSTANCEOF_EXPRESSION= 62;
/**
* Node type constant indicating a node of type <code>LineComment</code>.
*
* @see LineComment
* @since 3.0
*/
public static final int LINE_COMMENT= 63;
/**
* Node type constant indicating a node of type <code>BlockComment</code>.
*
* @see BlockComment
* @since 3.0
*/
public static final int BLOCK_COMMENT= 64;
/**
* Node type constant indicating a node of type <code>TagElement</code>.
*
* @see TagElement
* @since 3.0
*/
public static final int TAG_ELEMENT= 65;
/**
* Node type constant indicating a node of type <code>TextElement</code>.
*
* @see TextElement
* @since 3.0
*/
public static final int TEXT_ELEMENT= 66;
/**
* Node type constant indicating a node of type <code>MemberRef</code>.
*
* @see MemberRef
* @since 3.0
*/
public static final int MEMBER_REF= 67;
/**
* Node type constant indicating a node of type <code>MethodRef</code>.
*
* @see MethodRef
* @since 3.0
*/
public static final int METHOD_REF= 68;
/**
* Node type constant indicating a node of type <code>MethodRefParameter</code>.
*
* @see MethodRefParameter
* @since 3.0
*/
public static final int METHOD_REF_PARAMETER= 69;
/**
* Node type constant indicating a node of type <code>EnhancedForStatement</code>.
*
* @see EnhancedForStatement
* @since 3.1
*/
public static final int ENHANCED_FOR_STATEMENT= 70;
/**
* Node type constant indicating a node of type <code>EnumDeclaration</code>.
*
* @see EnumDeclaration
* @since 3.1
*/
public static final int ENUM_DECLARATION= 71;
/**
* Node type constant indicating a node of type <code>EnumConstantDeclaration</code>.
*
* @see EnumConstantDeclaration
* @since 3.1
*/
public static final int ENUM_CONSTANT_DECLARATION= 72;
/**
* Node type constant indicating a node of type <code>TypeParameter</code>.
*
* @see TypeParameter
* @since 3.1
*/
public static final int TYPE_PARAMETER= 73;
/**
* Node type constant indicating a node of type <code>ParameterizedType</code>.
*
* @see ParameterizedType
* @since 3.1
*/
public static final int PARAMETERIZED_TYPE= 74;
/**
* Node type constant indicating a node of type <code>QualifiedType</code>.
*
* @see QualifiedType
* @since 3.1
*/
public static final int QUALIFIED_TYPE= 75;
/**
* Node type constant indicating a node of type <code>WildcardType</code>.
*
* @see WildcardType
* @since 3.1
*/
public static final int WILDCARD_TYPE= 76;
/**
* Node type constant indicating a node of type <code>NormalAnnotation</code>.
*
* @see NormalAnnotation
* @since 3.1
*/
public static final int NORMAL_ANNOTATION= 77;
/**
* Node type constant indicating a node of type <code>MarkerAnnotation</code>.
*
* @see MarkerAnnotation
* @since 3.1
*/
public static final int MARKER_ANNOTATION= 78;
/**
* Node type constant indicating a node of type <code>SingleMemberAnnotation</code>.
*
* @see SingleMemberAnnotation
* @since 3.1
*/
public static final int SINGLE_MEMBER_ANNOTATION= 79;
/**
* Node type constant indicating a node of type <code>MemberValuePair</code>.
*
* @see MemberValuePair
* @since 3.1
*/
public static final int MEMBER_VALUE_PAIR= 80;
/**
* Node type constant indicating a node of type <code>AnnotationTypeDeclaration</code>.
*
* @see AnnotationTypeDeclaration
* @since 3.1
*/
public static final int ANNOTATION_TYPE_DECLARATION= 81;
/**
* Node type constant indicating a node of type <code>AnnotationTypeMemberDeclaration</code>.
*
* @see AnnotationTypeMemberDeclaration
* @since 3.1
*/
public static final int ANNOTATION_TYPE_MEMBER_DECLARATION= 82;
/**
* Node type constant indicating a node of type <code>Modifier</code>.
*
* @see Modifier
* @since 3.1
*/
public static final int MODIFIER= 83;
/**
* Returns the node class for the corresponding node type.
*
* @param nodeType AST node type
* @return the corresponding <code>ASTNode</code> subclass
* @exception IllegalArgumentException if <code>nodeType</code> is not a legal AST node type
* @see #getNodeType()
* @since 3.0
*/
public static Class nodeClassForType(int nodeType) {
switch (nodeType) {
case ANNOTATION_TYPE_DECLARATION:
return AnnotationTypeDeclaration.class;
case ANNOTATION_TYPE_MEMBER_DECLARATION:
return AnnotationTypeMemberDeclaration.class;
case ANONYMOUS_CLASS_DECLARATION:
return AnonymousClassDeclaration.class;
case ARRAY_ACCESS:
return ArrayAccess.class;
case ARRAY_CREATION:
return ArrayCreation.class;
case ARRAY_INITIALIZER:
return ArrayInitializer.class;
case ARRAY_TYPE:
return ArrayType.class;
case ASSERT_STATEMENT:
return AssertStatement.class;
case ASSIGNMENT:
return Assignment.class;
case BLOCK:
return Block.class;
case BLOCK_COMMENT:
return BlockComment.class;
case BOOLEAN_LITERAL:
return BooleanLiteral.class;
case BREAK_STATEMENT:
return BreakStatement.class;
case CAST_EXPRESSION:
return CastExpression.class;
case CATCH_CLAUSE:
return CatchClause.class;
case CHARACTER_LITERAL:
return CharacterLiteral.class;
case CLASS_INSTANCE_CREATION:
return ClassInstanceCreation.class;
case COMPILATION_UNIT:
return CompilationUnit.class;
case CONDITIONAL_EXPRESSION:
return ConditionalExpression.class;
case CONSTRUCTOR_INVOCATION:
return ConstructorInvocation.class;
case CONTINUE_STATEMENT:
return ContinueStatement.class;
case DO_STATEMENT:
return DoStatement.class;
case EMPTY_STATEMENT:
return EmptyStatement.class;
case ENHANCED_FOR_STATEMENT:
return EnhancedForStatement.class;
case ENUM_CONSTANT_DECLARATION:
return EnumConstantDeclaration.class;
case ENUM_DECLARATION:
return EnumDeclaration.class;
case EXPRESSION_STATEMENT:
return ExpressionStatement.class;
case FIELD_ACCESS:
return FieldAccess.class;
case FIELD_DECLARATION:
return FieldDeclaration.class;
case FOR_STATEMENT:
return ForStatement.class;
case IF_STATEMENT:
return IfStatement.class;
case IMPORT_DECLARATION:
return ImportDeclaration.class;
case INFIX_EXPRESSION:
return InfixExpression.class;
case INITIALIZER:
return Initializer.class;
case INSTANCEOF_EXPRESSION:
return InstanceofExpression.class;
case JAVADOC:
return Javadoc.class;
case LABELED_STATEMENT:
return LabeledStatement.class;
case LINE_COMMENT:
return LineComment.class;
case MARKER_ANNOTATION:
return MarkerAnnotation.class;
case MEMBER_REF:
return MemberRef.class;
case MEMBER_VALUE_PAIR:
return MemberValuePair.class;
case METHOD_DECLARATION:
return MethodDeclaration.class;
case METHOD_INVOCATION:
return MethodInvocation.class;
case METHOD_REF:
return MethodRef.class;
case METHOD_REF_PARAMETER:
return MethodRefParameter.class;
case MODIFIER:
return Modifier.class;
case NORMAL_ANNOTATION:
return NormalAnnotation.class;
case NULL_LITERAL:
return NullLiteral.class;
case NUMBER_LITERAL:
return NumberLiteral.class;
case PACKAGE_DECLARATION:
return PackageDeclaration.class;
case PARAMETERIZED_TYPE:
return ParameterizedType.class;
case PARENTHESIZED_EXPRESSION:
return ParenthesizedExpression.class;
case POSTFIX_EXPRESSION:
return PostfixExpression.class;
case PREFIX_EXPRESSION:
return PrefixExpression.class;
case PRIMITIVE_TYPE:
return PrimitiveType.class;
case QUALIFIED_NAME:
return QualifiedName.class;
case QUALIFIED_TYPE:
return QualifiedType.class;
case RETURN_STATEMENT:
return ReturnStatement.class;
case SIMPLE_NAME:
return SimpleName.class;
case SIMPLE_TYPE:
return SimpleType.class;
case SINGLE_MEMBER_ANNOTATION:
return SingleMemberAnnotation.class;
case SINGLE_VARIABLE_DECLARATION:
return SingleVariableDeclaration.class;
case STRING_LITERAL:
return StringLiteral.class;
case SUPER_CONSTRUCTOR_INVOCATION:
return SuperConstructorInvocation.class;
case SUPER_FIELD_ACCESS:
return SuperFieldAccess.class;
case SUPER_METHOD_INVOCATION:
return SuperMethodInvocation.class;
case SWITCH_CASE:
return SwitchCase.class;
case SWITCH_STATEMENT:
return SwitchStatement.class;
case SYNCHRONIZED_STATEMENT:
return SynchronizedStatement.class;
case TAG_ELEMENT:
return TagElement.class;
case TEXT_ELEMENT:
return TextElement.class;
case THIS_EXPRESSION:
return ThisExpression.class;
case THROW_STATEMENT:
return ThrowStatement.class;
case TRY_STATEMENT:
return TryStatement.class;
case TYPE_DECLARATION:
return TypeDeclaration.class;
case TYPE_DECLARATION_STATEMENT:
return TypeDeclarationStatement.class;
case TYPE_LITERAL:
return TypeLiteral.class;
case TYPE_PARAMETER:
return TypeParameter.class;
case VARIABLE_DECLARATION_EXPRESSION:
return VariableDeclarationExpression.class;
case VARIABLE_DECLARATION_FRAGMENT:
return VariableDeclarationFragment.class;
case VARIABLE_DECLARATION_STATEMENT:
return VariableDeclarationStatement.class;
case WHILE_STATEMENT:
return WhileStatement.class;
case WILDCARD_TYPE:
return WildcardType.class;
}
throw new IllegalArgumentException();
}
/**
* Owning AST.
* <p>
* N.B. This ia a private field, but declared as package-visible for more efficient access from
* inner classes.
* </p>
*/
final AST ast;
/**
* Parent AST node, or <code>null</code> if this node is a root. Initially <code>null</code>.
*/
private ASTNode parent= null;
/**
* An unmodifiable empty map (used to implement <code>properties()</code>).
*/
private static final Map UNMODIFIABLE_EMPTY_MAP= Collections.unmodifiableMap(new HashMap(1));
/**
* Primary field used in representing node properties efficiently. If <code>null</code>, this
* node has no properties. If a <code>String</code>, this is the name of this node's sole
* property, and <code>property2</code> contains its value. If a <code>HashMap</code>, this is
* the table of property name-value mappings; <code>property2</code>, if non-null is its
* unmodifiable equivalent. Initially <code>null</code>.
*
* @see #property2
*/
private Object property1= null;
/**
* Auxillary field used in representing node properties efficiently.
*
* @see #property1
*/
private Object property2= null;
/**
* A character index into the original source string, or <code>-1</code> if no source position
* information is available for this node; <code>-1</code> by default.
*/
private int startPosition= -1;
/**
* A character length, or <code>0</code> if no source position information is recorded for this
* node; <code>0</code> by default.
*/
private int length= 0;
/**
* Flag constant (bit mask, value 1) indicating that there is something not quite right with
* this AST node.
* <p>
* The standard parser (<code>ASTParser</code>) sets this flag on a node to indicate a syntax
* error detected in the vicinity.
* </p>
*/
public static final int MALFORMED= 1;
/**
* Flag constant (bit mask, value 2) indicating that this is a node that was created by the
* parser (as opposed to one created by another party).
* <p>
* The standard parser (<code>ASTParser</code>) sets this flag on the nodes it creates.
* </p>
*
* @since 3.0
*/
public static final int ORIGINAL= 2;
/**
* Flag constant (bit mask, value 4) indicating that this node is unmodifiable. When a node is
* marked unmodifiable, the following operations result in a runtime exception:
* <ul>
* <li>Change a simple property of this node.</li>
* <li>Add or remove a child node from this node.</li>
* <li>Parent (or reparent) this node.</li>
* </ul>
* <p>
* The standard parser (<code>ASTParser</code>) does not set this flag on the nodes it creates.
* However, clients may set this flag on a node to prevent further modification of the its
* structural properties.
* </p>
*
* @since 3.0
*/
public static final int PROTECT= 4;
/**
* Flag constant (bit mask, value 8) indicating that this node or a part of this node is
* recovered from source that contains a syntax error detected in the vicinity.
* <p>
* The standard parser (<code>ASTParser</code>) sets this flag on a node to indicate a recovered
* node.
* </p>
*
* @since 3.2
*/
public static final int RECOVERED= 8;
/**
* int containing the node type in the top 16 bits and flags in the bottom 16 bits; none set by
* default.
* <p>
* N.B. This is a private field, but declared as package-visible for more efficient access from
* inner classes.
* </p>
*
* @see #MALFORMED
*/
int typeAndFlags= 0;
/**
* Property of parent in which this node is a child, or <code>null</code> if this node is a
* root. Initially <code>null</code>.
*
* @see #getLocationInParent
* @since 3.0
*/
private StructuralPropertyDescriptor location= null;
/**
* Internal convenience constant indicating that there is definite risk of cycles.
*
* @since 3.0
*/
static final boolean CYCLE_RISK= true;
/**
* Internal convenience constant indicating that there is no risk of cycles.
*
* @since 3.0
*/
static final boolean NO_CYCLE_RISK= false;
/**
* Internal convenience constant indicating that a structural property is mandatory.
*
* @since 3.0
*/
static final boolean MANDATORY= true;
/**
* Internal convenience constant indicating that a structural property is optional.
*
* @since 3.0
*/
static final boolean OPTIONAL= false;
/**
* A specialized implementation of a list of ASTNodes. The implementation is based on an
* ArrayList.
*/
class NodeList extends AbstractList {
/**
* The underlying list in which the nodes of this list are stored (element type:
* <code>ASTNode</code>).
* <p>
* Be stingy on storage - assume that list will be empty.
* </p>
* <p>
* This field declared default visibility (rather than private) so that accesses from
* <code>NodeList.Cursor</code> do not require a synthetic accessor method.
* </p>
*/
ArrayList store= new ArrayList(0);
/**
* The property descriptor for this list.
*/
ChildListPropertyDescriptor propertyDescriptor;
/**
* A cursor for iterating over the elements of the list. Does not lose its position if the
* list is changed during the iteration.
*/
class Cursor implements Iterator {
/**
* The position of the cursor between elements. If the value is N, then the cursor sits
* between the element at positions N-1 and N. Initially just before the first element
* of the list.
*/
private int position= 0;
/* (non-Javadoc)
* Method declared on <code>Iterator</code>.
*/
public boolean hasNext() {
return this.position < NodeList.this.store.size();
}
/* (non-Javadoc)
* Method declared on <code>Iterator</code>.
*/
public Object next() {
Object result= NodeList.this.store.get(this.position);
this.position++;
return result;
}
/* (non-Javadoc)
* Method declared on <code>Iterator</code>.
*/
public void remove() {
throw new UnsupportedOperationException();
}
/**
* Adjusts this cursor to accomodate an add/remove at the given index.
*
* @param index the position at which the element was added or removed
* @param delta +1 for add, and -1 for remove
*/
void update(int index, int delta) {
if (this.position > index) {
// the cursor has passed the added or removed element
this.position+= delta;
}
}
}
/**
* A list of currently active cursors (element type: <code>Cursor</code>), or
* <code>null</code> if there are no active cursors.
* <p>
* It is important for storage considerations to maintain the null-means-empty invariant;
* otherwise, every NodeList instance will waste a lot of space. A cursor is needed only for
* the duration of a visit to the child nodes. Under normal circumstances, only a single
* cursor is needed; multiple cursors are only required if there are multiple visits going
* on at the same time.
* </p>
*/
private List cursors= null;
/**
* Creates a new empty list of nodes owned by this node. This node will be the common parent
* of all nodes added to this list.
*
* @param property the property descriptor
* @since 3.0
*/
NodeList(ChildListPropertyDescriptor property) {
super();
this.propertyDescriptor= property;
}
/* (non-javadoc)
* @see java.util.AbstractCollection#size()
*/
public int size() {
return this.store.size();
}
/* (non-javadoc)
* @see AbstractList#get(int)
*/
public Object get(int index) {
return this.store.get(index);
}
/* (non-javadoc)
* @see List#set(int, java.lang.Object)
*/
public Object set(int index, Object element) {
if (element == null) {
throw new IllegalArgumentException();
}
if ((ASTNode.this.typeAndFlags & PROTECT) != 0) {
// this node is protected => cannot gain or lose children
throw new IllegalArgumentException("AST node cannot be modified"); //$NON-NLS-1$
}
// delink old child from parent, and link new child to parent
ASTNode newChild= (ASTNode)element;
ASTNode oldChild= (ASTNode)this.store.get(index);
if (oldChild == newChild) {
return oldChild;
}
if ((oldChild.typeAndFlags & PROTECT) != 0) {
// old child is protected => cannot be unparented
throw new IllegalArgumentException("AST node cannot be modified"); //$NON-NLS-1$
}
ASTNode.checkNewChild(ASTNode.this, newChild, this.propertyDescriptor.cycleRisk, this.propertyDescriptor.elementType);
ASTNode.this.ast.preReplaceChildEvent(ASTNode.this, oldChild, newChild, this.propertyDescriptor);
Object result= this.store.set(index, newChild);
// n.b. setParent will call ast.modifying()
oldChild.setParent(null, null);
newChild.setParent(ASTNode.this, this.propertyDescriptor);
ASTNode.this.ast.postReplaceChildEvent(ASTNode.this, oldChild, newChild, this.propertyDescriptor);
return result;
}
/* (non-javadoc)
* @see List#add(int, java.lang.Object)
*/
public void add(int index, Object element) {
if (element == null) {
throw new IllegalArgumentException();
}
if ((ASTNode.this.typeAndFlags & PROTECT) != 0) {
// this node is protected => cannot gain or lose children
throw new IllegalArgumentException("AST node cannot be modified"); //$NON-NLS-1$
}
// link new child to parent
ASTNode newChild= (ASTNode)element;
ASTNode.checkNewChild(ASTNode.this, newChild, this.propertyDescriptor.cycleRisk, this.propertyDescriptor.elementType);
ASTNode.this.ast.preAddChildEvent(ASTNode.this, newChild, this.propertyDescriptor);
this.store.add(index, element);
updateCursors(index, +1);
// n.b. setParent will call ast.modifying()
newChild.setParent(ASTNode.this, this.propertyDescriptor);
ASTNode.this.ast.postAddChildEvent(ASTNode.this, newChild, this.propertyDescriptor);
}
/* (non-javadoc)
* @see List#remove(int)
*/
public Object remove(int index) {
if ((ASTNode.this.typeAndFlags & PROTECT) != 0) {
// this node is protected => cannot gain or lose children
throw new IllegalArgumentException("AST node cannot be modified"); //$NON-NLS-1$
}
// delink old child from parent
ASTNode oldChild= (ASTNode)this.store.get(index);
if ((oldChild.typeAndFlags & PROTECT) != 0) {
// old child is protected => cannot be unparented
throw new IllegalArgumentException("AST node cannot be modified"); //$NON-NLS-1$
}
ASTNode.this.ast.preRemoveChildEvent(ASTNode.this, oldChild, this.propertyDescriptor);
// n.b. setParent will call ast.modifying()
oldChild.setParent(null, null);
Object result= this.store.remove(index);
updateCursors(index, -1);
ASTNode.this.ast.postRemoveChildEvent(ASTNode.this, oldChild, this.propertyDescriptor);
return result;
}
/**
* Allocate a cursor to use for a visit. The client must call <code>releaseCursor</code>
* when done.
* <p>
* This method is internally synchronized on this NodeList. It is thread-safe to create a
* cursor.
* </p>
*
* @return a new cursor positioned before the first element of the list
*/
Cursor newCursor() {
synchronized (this) {
// serialize cursor management on this NodeList
if (this.cursors == null) {
// convert null to empty list
this.cursors= new ArrayList(1);
}
Cursor result= new Cursor();
this.cursors.add(result);
return result;
}
}
/**
* Releases the given cursor at the end of a visit.
* <p>
* This method is internally synchronized on this NodeList. It is thread-safe to release a
* cursor.
* </p>
*
* @param cursor the cursor
*/
void releaseCursor(Cursor cursor) {
synchronized (this) {
// serialize cursor management on this NodeList
this.cursors.remove(cursor);
if (this.cursors.isEmpty()) {
// important: convert empty list back to null
// otherwise the node will hang on to needless junk
this.cursors= null;
}
}
}
/**
* Adjusts all cursors to accomodate an add/remove at the given index.
* <p>
* This method is only used when the list is being modified. The AST is not thread-safe if
* any of the clients are modifying it.
* </p>
*
* @param index the position at which the element was added or removed
* @param delta +1 for add, and -1 for remove
*/
private synchronized void updateCursors(int index, int delta) {
if (this.cursors == null) {
// there are no cursors to worry about
return;
}
for (Iterator it= this.cursors.iterator(); it.hasNext();) {
Cursor c= (Cursor)it.next();
c.update(index, delta);
}
}
/**
* Returns an estimate of the memory footprint of this node list instance in bytes.
* <ul>
* <li>1 object header for the NodeList instance</li>
* <li>5 4-byte fields of the NodeList instance</li>
* <li>0 for cursors since null unless walk in progress</li>
* <li>1 object header for the ArrayList instance</li>
* <li>2 4-byte fields of the ArrayList instance</li>
* <li>1 object header for an Object[] instance</li>
* <li>4 bytes in array for each element</li>
* </ul>
*
* @return the size of this node list in bytes
*/
int memSize() {
int result= HEADERS + 5 * 4;
result+= HEADERS + 2 * 4;
result+= HEADERS + 4 * size();
return result;
}
/**
* Returns an estimate of the memory footprint in bytes of this node list and all its
* subtrees.
*
* @return the size of this list of subtrees in bytes
*/
int listSize() {
int result= memSize();
for (Iterator it= iterator(); it.hasNext();) {
ASTNode child= (ASTNode)it.next();
result+= child.treeSize();
}
return result;
}
}
/**
* Creates a new AST node owned by the given AST. Once established, the relationship between an
* AST node and its owning AST does not change over the lifetime of the node. The new node has
* no parent node, and no properties.
* <p>
* N.B. This constructor is package-private; all subclasses my be declared in the same package;
* clients are unable to declare additional subclasses.
* </p>
*
* @param ast the AST that is to own this node
*/
ASTNode(AST ast) {
if (ast == null) {
throw new IllegalArgumentException();
}
this.ast= ast;
setNodeType(getNodeType0());
setFlags(ast.getDefaultNodeFlag());
// setFlags calls modifying();
}
/**
* Returns this node's AST.
* <p>
* Note that the relationship between an AST node and its owing AST does not change over the
* lifetime of a node.
* </p>
*
* @return the AST that owns this node
*/
public final AST getAST() {
return this.ast;
}
/**
* Returns this node's parent node, or <code>null</code> if this is the root node.
* <p>
* Note that the relationship between an AST node and its parent node may change over the
* lifetime of a node.
* </p>
*
* @return the parent of this node, or <code>null</code> if none
*/
public final ASTNode getParent() {
return this.parent;
}
/**
* Returns the location of this node within its parent, or <code>null</code> if this is a root
* node.
* <p>
*
* <pre>
* ASTNode node = ...;
* ASTNode parent = node.getParent();
* StructuralPropertyDescriptor location = node.getLocationInParent();
* assert (parent != null) == (location != null);
* if ((location != null) && location.isChildProperty())
* assert parent.getStructuralProperty(location) == node;
* if ((location != null) && location.isChildListProperty())
* assert ((List) parent.getStructuralProperty(location)).contains(node);
* </pre>
*
* </p>
* <p>
* Note that the relationship between an AST node and its parent node may change over the
* lifetime of a node.
* </p>
*
* @return the location of this node in its parent, or <code>null</code> if this node has no
* parent
* @since 3.0
*/
public final StructuralPropertyDescriptor getLocationInParent() {
return this.location;
}
/**
* Returns the root node at or above this node; returns this node if it is a root.
*
* @return the root node at or above this node
*/
public final ASTNode getRoot() {
ASTNode candidate= this;
while (true) {
ASTNode p= candidate.getParent();
if (p == null) {
// candidate has no parent - that's the guy
return candidate;
}
candidate= p;
}
}
/**
* Returns the value of the given structural property for this node. The value returned depends
* on the kind of property:
* <ul>
* <li>{@link SimplePropertyDescriptor} - the value of the given simple property, or
* <code>null</code> if none; primitive values are "boxed"</li>
* <li>{@link ChildPropertyDescriptor} - the child node (type <code>ASTNode</code>), or
* <code>null</code> if none</li>
* <li>{@link ChildListPropertyDescriptor} - the list (element type: {@link ASTNode})</li>
* </ul>
*
* @param property the property
* @return the value, or <code>null</code> if none
* @exception RuntimeException if this node does not have the given property
* @since 3.0
*/
public final Object getStructuralProperty(StructuralPropertyDescriptor property) {
if (property instanceof SimplePropertyDescriptor) {
SimplePropertyDescriptor p= (SimplePropertyDescriptor)property;
if (p.getValueType() == int.class) {
int result= internalGetSetIntProperty(p, true, 0);
return new Integer(result);
} else if (p.getValueType() == boolean.class) {
boolean result= internalGetSetBooleanProperty(p, true, false);
return Boolean.valueOf(result);
} else {
return internalGetSetObjectProperty(p, true, null);
}
}
if (property instanceof ChildPropertyDescriptor) {
return internalGetSetChildProperty((ChildPropertyDescriptor)property, true, null);
}
if (property instanceof ChildListPropertyDescriptor) {
return internalGetChildListProperty((ChildListPropertyDescriptor)property);
}
throw new IllegalArgumentException();
}
/**
* Sets the value of the given structural property for this node. The value passed depends on
* the kind of property:
* <ul>
* <li>{@link SimplePropertyDescriptor} - the new value of the given simple property, or
* <code>null</code> if none; primitive values are "boxed"</li>
* <li>{@link ChildPropertyDescriptor} - the new child node (type <code>ASTNode</code>), or
* <code>null</code> if none</li>
* <li>{@link ChildListPropertyDescriptor} - not allowed</li>
* </ul>
*
* @param property the property
* @param value the property value
* @exception RuntimeException if this node does not have the given property, or if the given
* property cannot be set
* @since 3.0
*/
public final void setStructuralProperty(StructuralPropertyDescriptor property, Object value) {
if (property instanceof SimplePropertyDescriptor) {
SimplePropertyDescriptor p= (SimplePropertyDescriptor)property;
if (p.getValueType() == int.class) {
int arg= ((Integer)value).intValue();
internalGetSetIntProperty(p, false, arg);
return;
} else if (p.getValueType() == boolean.class) {
boolean arg= ((Boolean)value).booleanValue();
internalGetSetBooleanProperty(p, false, arg);
return;
} else {
if (value == null && p.isMandatory()) {
throw new IllegalArgumentException();
}
internalGetSetObjectProperty(p, false, value);
return;
}
}
if (property instanceof ChildPropertyDescriptor) {
ChildPropertyDescriptor p= (ChildPropertyDescriptor)property;
ASTNode child= (ASTNode)value;
if (child == null && p.isMandatory()) {
throw new IllegalArgumentException();
}
internalGetSetChildProperty(p, false, child);
return;
}
if (property instanceof ChildListPropertyDescriptor) {
throw new IllegalArgumentException("Cannot set the list of child list property"); //$NON-NLS-1$
}
}
/**
* Sets the value of the given int-valued property for this node. The default implementation of
* this method throws an exception explaining that this node does not have such a property. This
* method should be extended in subclasses that have at leasy one simple property whose value
* type is int.
*
* @param property the property
* @param get <code>true</code> for a get operation, and <code>false</code> for a set operation
* @param value the new property value; ignored for get operations
* @return the value; always returns <code>0</code> for set operations
* @exception RuntimeException if this node does not have the given property, or if the given
* value cannot be set as specified
* @since 3.0
*/
int internalGetSetIntProperty(SimplePropertyDescriptor property, boolean get, int value) {
throw new RuntimeException("Node does not have this property"); //$NON-NLS-1$
}
/**
* Sets the value of the given boolean-valued property for this node. The default implementation
* of this method throws an exception explaining that this node does not have such a property.
* This method should be extended in subclasses that have at leasy one simple property whose
* value type is boolean.
*
* @param property the property
* @param get <code>true</code> for a get operation, and <code>false</code> for a set operation
* @param value the new property value; ignored for get operations
* @return the value; always returns <code>false</code> for set operations
* @exception RuntimeException if this node does not have the given property, or if the given
* value cannot be set as specified
* @since 3.0
*/
boolean internalGetSetBooleanProperty(SimplePropertyDescriptor property, boolean get, boolean value) {
throw new RuntimeException("Node does not have this property"); //$NON-NLS-1$
}
/**
* Sets the value of the given property for this node. The default implementation of this method
* throws an exception explaining that this node does not have such a property. This method
* should be extended in subclasses that have at leasy one simple property whose value type is a
* reference type.
*
* @param property the property
* @param get <code>true</code> for a get operation, and <code>false</code> for a set operation
* @param value the new property value, or <code>null</code> if none; ignored for get operations
* @return the value, or <code>null</code> if none; always returns <code>null</code> for set
* operations
* @exception RuntimeException if this node does not have the given property, or if the given
* value cannot be set as specified
* @since 3.0
*/
Object internalGetSetObjectProperty(SimplePropertyDescriptor property, boolean get, Object value) {
throw new RuntimeException("Node does not have this property"); //$NON-NLS-1$
}
/**
* Sets the child value of the given property for this node. The default implementation of this
* method throws an exception explaining that this node does not have such a property. This
* method should be extended in subclasses that have at leasy one child property.
*
* @param property the property
* @param get <code>true</code> for a get operation, and <code>false</code> for a set operation
* @param child the new child value, or <code>null</code> if none; always <code>null</code> for
* get operations
* @return the child, or <code>null</code> if none; always returns <code>null</code> for set
* operations
* @exception RuntimeException if this node does not have the given property, or if the given
* child cannot be set as specified
* @since 3.0
*/
ASTNode internalGetSetChildProperty(ChildPropertyDescriptor property, boolean get, ASTNode child) {
throw new RuntimeException("Node does not have this property"); //$NON-NLS-1$
}
/**
* Returns the list value of the given property for this node. The default implementation of
* this method throws an exception explaining that this noed does not have such a property. This
* method should be extended in subclasses that have at leasy one child list property.
*
* @param property the property
* @return the list (element type: {@link ASTNode})
* @exception RuntimeException if the given node does not have the given property
* @since 3.0
*/
List internalGetChildListProperty(ChildListPropertyDescriptor property) {
throw new RuntimeException("Node does not have this property"); //$NON-NLS-1$
}
/**
* Returns a list of structural property descriptors for nodes of the same type as this node.
* Clients must not modify the result.
* <p>
* Note that property descriptors are a meta-level mechanism for manipulating ASTNodes in a
* generic way. They are unrelated to <code>get/setProperty</code>.
* </p>
*
* @return a list of property descriptors (element type: {@link StructuralPropertyDescriptor})
* @since 3.0
*/
public final List structuralPropertiesForType() {
return internalStructuralPropertiesForType(this.ast.apiLevel);
}
/**
* Returns a list of property descriptors for this node type. Clients must not modify the
* result. This abstract method must be implemented in each concrete AST node type.
* <p>
* N.B. This method is package-private, so that the implementations of this method in each of
* the concrete AST node types do not clutter up the API doc.
* </p>
*
* @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
*/
abstract List internalStructuralPropertiesForType(int apiLevel);
/**
* Internal helper method that starts the building a list of property descriptors for the given
* node type.
*
* @param nodeClass the class for a concrete node type
* @param propertyList empty list
*/
static void createPropertyList(Class nodeClass, List propertyList) {
// stuff nodeClass at head of list for future ref
propertyList.add(nodeClass);
}
/**
* Internal helper method that adding a property descriptor.
*
* @param property the structural property descriptor
* @param propertyList list beginning with the AST node class followed by accumulated structural
* property descriptors
*/
static void addProperty(StructuralPropertyDescriptor property, List propertyList) {
Class nodeClass= (Class)propertyList.get(0);
if (property.getNodeClass() != nodeClass) {
// easily made cut-and-paste mistake
throw new RuntimeException("Structural property descriptor has wrong node class!"); //$NON-NLS-1$
}
propertyList.add(property);
}
/**
* Internal helper method that completes the building of a node type's structural property
* descriptor list.
*
* @param propertyList list beginning with the AST node class followed by accumulated structural
* property descriptors
* @return unmodifiable list of structural property descriptors (element type:
* <code>StructuralPropertyDescriptor</code>)
*/
static List reapPropertyList(List propertyList) {
propertyList.remove(0); // remove nodeClass
// compact
ArrayList a= new ArrayList(propertyList.size());
a.addAll(propertyList);
return Collections.unmodifiableList(a);
}
/**
* Checks that this AST operation is not used when building JLS2 level ASTs.
*
* @exception UnsupportedOperationException
* @since 3.0
*/
final void unsupportedIn2() {
if (this.ast.apiLevel == AST.JLS2_INTERNAL) {
throw new UnsupportedOperationException("Operation not supported in JLS2 AST"); //$NON-NLS-1$
}
}
/**
* Checks that this AST operation is only used when building JLS2 level ASTs.
*
* @exception UnsupportedOperationException
* @since 3.0
*/
final void supportedOnlyIn2() {
if (this.ast.apiLevel != AST.JLS2_INTERNAL) {
throw new UnsupportedOperationException("Operation only supported in JLS2 AST"); //$NON-NLS-1$
}
}
/**
* Sets or clears this node's parent node and location.
* <p>
* Note that this method is package-private. The pointer from a node to its parent is set
* implicitly as a side effect of inserting or removing the node as a child of another node.
* This method calls <code>ast.modifying()</code>.
* </p>
*
* @param parent the new parent of this node, or <code>null</code> if none
* @param property the location of this node in its parent, or <code>null</code> if
* <code>parent</code> is <code>null</code>
* @see #getLocationInParent
* @see #getParent
* @since 3.0
*/
final void setParent(ASTNode parent, StructuralPropertyDescriptor property) {
this.ast.modifying();
this.parent= parent;
this.location= property;
}
/**
* Removes this node from its parent. Has no effect if this node is unparented. If this node
* appears as an element of a child list property of its parent, then this node is removed from
* the list using <code>List.remove</code>. If this node appears as the value of a child
* property of its parent, then this node is detached from its parent by passing
* <code>null</code> to the appropriate setter method; this operation fails if this node is in a
* mandatory property.
*
* @since 3.0
*/
public final void delete() {
StructuralPropertyDescriptor p= getLocationInParent();
if (p == null) {
// node is unparented
return;
}
if (p.isChildProperty()) {
getParent().setStructuralProperty(this.location, null);
return;
}
if (p.isChildListProperty()) {
List l= (List)getParent().getStructuralProperty(this.location);
l.remove(this);
}
}
/**
* Checks whether the given new child node is a node in a different AST from its parent-to-be,
* whether it is already has a parent, whether adding it to its parent-to-be would create a
* cycle, and whether the child is of the right type. The parent-to-be is the enclosing
* instance.
*
* @param node the parent-to-be node
* @param newChild the new child of the parent
* @param cycleCheck <code>true</code> if cycles are possible and need to be checked,
* <code>false</code> if cycles are impossible and do not need to be checked
* @param nodeType a type constraint on child nodes, or <code>null</code> if no special check is
* required
* @exception IllegalArgumentException if:
* <ul>
* <li>the child is null</li>
* <li>the node belongs to a different AST</li>
* <li>the child has the incorrect node type</li>
* <li>the node already has a parent</li>
* <li>a cycle in would be created</li>
* </ul>
*/
static void checkNewChild(ASTNode node, ASTNode newChild,
boolean cycleCheck, Class nodeType) {
if (newChild.ast != node.ast) {
// new child is from a different AST
throw new IllegalArgumentException();
}
if (newChild.getParent() != null) {
// new child currently has a different parent
throw new IllegalArgumentException();
}
if (cycleCheck && newChild == node.getRoot()) {
// inserting new child would create a cycle
throw new IllegalArgumentException();
}
Class childClass= newChild.getClass();
if (nodeType != null && !nodeType.isAssignableFrom(childClass)) {
// new child is not of the right type
throw new ClassCastException();
}
if ((newChild.typeAndFlags & PROTECT) != 0) {
// new child node is protected => cannot be parented
throw new IllegalArgumentException("AST node cannot be modified"); //$NON-NLS-1$
}
}
/**
* Prelude portion of the "3 step program" for replacing the old child of this node with another
* node. Here is the code pattern found in all AST node subclasses:
*
* <pre>
* ASTNode oldChild= this.foo;
* preReplaceChild(oldChild, newFoo, FOO_PROPERTY);
* this.foo= newFoo;
* postReplaceChild(oldChild, newFoo, FOO_PROPERTY);
* </pre>
*
* The first part (preReplaceChild) does all the precondition checks, reports pre-delete events,
* and changes parent links. The old child is delinked from its parent (making it a root node),
* and the new child node is linked to its parent. The new child node must be a root node in the
* same AST as its new parent, and must not be an ancestor of this node. All three nodes must be
* modifiable (not PROTECTED). The replace operation must fail atomically; so it is crucial that
* all precondition checks be done before any linking and delinking happens. The final part
* (postReplaceChild )reports post-add events.
* <p>
* This method calls <code>ast.modifying()</code> for the nodes affected.
* </p>
*
* @param oldChild the old child of this node, or <code>null</code> if there was no old child to
* replace
* @param newChild the new child of this node, or <code>null</code> if there is no replacement
* child
* @param property the property descriptor of this node describing the relationship between node
* and child
* @exception RuntimeException if:
* <ul>
* <li>the node belongs to a different AST</li>
* <li>the node already has a parent</li>
* <li>a cycle in would be created</li>
* <li>any of the nodes involved are unmodifiable</li>
* </ul>
* @since 3.0
*/
final void preReplaceChild(ASTNode oldChild, ASTNode newChild, ChildPropertyDescriptor property) {
if ((this.typeAndFlags & PROTECT) != 0) {
// this node is protected => cannot gain or lose children
throw new IllegalArgumentException("AST node cannot be modified"); //$NON-NLS-1$
}
if (newChild != null) {
checkNewChild(this, newChild, property.cycleRisk, null);
}
// delink old child from parent
if (oldChild != null) {
if ((oldChild.typeAndFlags & PROTECT) != 0) {
// old child node is protected => cannot be unparented
throw new IllegalArgumentException("AST node cannot be modified"); //$NON-NLS-1$
}
if (newChild != null) {
this.ast.preReplaceChildEvent(this, oldChild, newChild, property);
} else {
this.ast.preRemoveChildEvent(this, oldChild, property);
}
oldChild.setParent(null, null);
} else {
if (newChild != null) {
this.ast.preAddChildEvent(this, newChild, property);
}
}
// link new child to parent
if (newChild != null) {
newChild.setParent(this, property);
// cannot notify postAddChildEvent until parent is linked to child too
}
}
/**
* Postlude portion of the "3 step program" for replacing the old child of this node with
* another node. See {@link #preReplaceChild(ASTNode, ASTNode, ChildPropertyDescriptor)} for
* details.
*
* @since 3.0
*/
final void postReplaceChild(ASTNode oldChild, ASTNode newChild, ChildPropertyDescriptor property) {
// link new child to parent
if (newChild != null) {
if (oldChild != null) {
this.ast.postReplaceChildEvent(this, oldChild, newChild, property);
} else {
this.ast.postAddChildEvent(this, newChild, property);
}
} else {
this.ast.postRemoveChildEvent(this, oldChild, property);
}
}
/**
* Prelude portion of the "3 step program" for changing the value of a simple property of this
* node. Here is the code pattern found in all AST node subclasses:
*
* <pre>
* preValueChange(FOO_PROPERTY);
* this.foo= newFoo;
* postValueChange(FOO_PROPERTY);
* </pre>
*
* The first part (preValueChange) does the precondition check to make sure the node is
* modifiable (not PROTECTED). The change operation must fail atomically; so it is crucial that
* the precondition checks are done before the field is hammered. The final part
* (postValueChange)reports post-change events.
* <p>
* This method calls <code>ast.modifying()</code> for the node affected.
* </p>
*
* @param property the property descriptor of this node
* @exception RuntimeException if:
* <ul>
* <li>this node is unmodifiable</li>
* </ul>
* @since 3.0
*/
final void preValueChange(SimplePropertyDescriptor property) {
if ((this.typeAndFlags & PROTECT) != 0) {
// this node is protected => cannot change valure of properties
throw new IllegalArgumentException("AST node cannot be modified"); //$NON-NLS-1$
}
this.ast.preValueChangeEvent(this, property);
this.ast.modifying();
}
/**
* Postlude portion of the "3 step program" for replacing the old child of this node with
* another node. See {@link #preValueChange(SimplePropertyDescriptor)} for details.
*
* @since 3.0
*/
final void postValueChange(SimplePropertyDescriptor property) {
this.ast.postValueChangeEvent(this, property);
}
/**
* Ensures that this node is modifiable (that is, not marked PROTECTED). If successful, calls
* ast.modifying().
*
* @exception RuntimeException is not modifiable
*/
final void checkModifiable() {
if ((this.typeAndFlags & PROTECT) != 0) {
throw new IllegalArgumentException("AST node cannot be modified"); //$NON-NLS-1$
}
this.ast.modifying();
}
/**
* Begin lazy initialization of this node. Here is the code pattern found in all AST node
* subclasses:
*
* <pre>
* if (this.foo == null) {
* // lazy init must be thread-safe for readers
* synchronized (this) {
* if (this.foo == null) {
* preLazyInit();
* this.foo = ...; // code to create new node
* postLazyInit(this.foo, FOO_PROPERTY);
* }
* }
* }
* </pre>
*
* @since 3.0
*/
final void preLazyInit() {
// IMPORTANT: this method is called by readers
// ASTNode.this is locked at this point
this.ast.disableEvents();
// will turn events back on in postLasyInit
}
/**
* End lazy initialization of this node.
*
* @param newChild the new child of this node, or <code>null</code> if there is no replacement
* child
* @param property the property descriptor of this node describing the relationship between node
* and child
* @since 3.0
*/
final void postLazyInit(ASTNode newChild, ChildPropertyDescriptor property) {
// IMPORTANT: this method is called by readers
// ASTNode.this is locked at this point
// newChild is brand new (so no chance of concurrent access)
newChild.setParent(this, property);
// turn events back on (they were turned off in corresponding preLazyInit)
this.ast.reenableEvents();
}
/**
* Returns the named property of this node, or <code>null</code> if none.
*
* @param propertyName the property name
* @return the property value, or <code>null</code> if none
* @see #setProperty(String,Object)
*/
public final Object getProperty(String propertyName) {
if (propertyName == null) {
throw new IllegalArgumentException();
}
if (this.property1 == null) {
// node has no properties at all
return null;
}
if (this.property1 instanceof String) {
// node has only a single property
if (propertyName.equals(this.property1)) {
return this.property2;
} else {
return null;
}
}
// otherwise node has table of properties
Map m= (Map)this.property1;
return m.get(propertyName);
}
/**
* Sets the named property of this node to the given value, or to <code>null</code> to clear it.
* <p>
* Clients should employ property names that are sufficiently unique to avoid inadvertent
* conflicts with other clients that might also be setting properties on the same node.
* </p>
* <p>
* Note that modifying a property is not considered a modification to the AST itself. This is to
* allow clients to decorate existing nodes with their own properties without jeopardizing
* certain things (like the validity of bindings), which rely on the underlying tree remaining
* static.
* </p>
*
* @param propertyName the property name
* @param data the new property value, or <code>null</code> if none
* @see #getProperty(String)
*/
public final void setProperty(String propertyName, Object data) {
if (propertyName == null) {
throw new IllegalArgumentException();
}
// N.B. DO NOT CALL ast.modifying();
if (this.property1 == null) {
// node has no properties at all
if (data == null) {
// we already know this
return;
}
// node gets its fist property
this.property1= propertyName;
this.property2= data;
return;
}
if (this.property1 instanceof String) {
// node has only a single property
if (propertyName.equals(this.property1)) {
// we're in luck
this.property2= data;
if (data == null) {
// just deleted last property
this.property1= null;
this.property2= null;
}
return;
}
if (data == null) {
// we already know this
return;
}
// node already has one property - getting its second
// convert to more flexible representation
HashMap m= new HashMap(2);
m.put(this.property1, this.property2);
m.put(propertyName, data);
this.property1= m;
this.property2= null;
return;
}
// node has two or more properties
HashMap m= (HashMap)this.property1;
if (data == null) {
m.remove(propertyName);
// check for just one property left
if (m.size() == 1) {
// convert to more efficient representation
Map.Entry[] entries= (Map.Entry[])m.entrySet().toArray(new Map.Entry[1]);
this.property1= entries[0].getKey();
this.property2= entries[0].getValue();
}
return;
} else {
m.put(propertyName, data);
// still has two or more properties
return;
}
}
/**
* Returns an unmodifiable table of the properties of this node with non-<code>null</code>
* values.
*
* @return the table of property values keyed by property name (key type: <code>String</code>;
* value type: <code>Object</code>)
*/
public final Map properties() {
if (this.property1 == null) {
// node has no properties at all
return UNMODIFIABLE_EMPTY_MAP;
}
if (this.property1 instanceof String) {
// node has a single property
return Collections.singletonMap(this.property1, this.property2);
}
// node has two or more properties
if (this.property2 == null) {
this.property2= Collections.unmodifiableMap((Map)this.property1);
}
// property2 is unmodifiable wrapper for map in property1
return (Map)this.property2;
}
/**
* Returns the flags associated with this node.
* <p>
* No flags are associated with newly created nodes.
* </p>
* <p>
* The flags are the bitwise-or of individual flags. The following flags are currently defined:
* <ul>
* <li>{@link #MALFORMED} - indicates node is syntactically malformed</li>
* <li>{@link #ORIGINAL} - indicates original node created by ASTParser</li>
* <li>{@link #PROTECT} - indicates node is protected from further modification</li>
* <li>{@link #RECOVERED} - indicates node or a part of this node is recovered from source that
* contains a syntax error</li>
* </ul>
* Other bit positions are reserved for future use.
* </p>
*
* @return the bitwise-or of individual flags
* @see #setFlags(int)
*/
public final int getFlags() {
return this.typeAndFlags & 0xFFFF;
}
/**
* Sets the flags associated with this node to the given value.
* <p>
* The flags are the bitwise-or of individual flags. The following flags are currently defined:
* <ul>
* <li>{@link #MALFORMED} - indicates node is syntactically malformed</li>
* <li>{@link #ORIGINAL} - indicates original node created by ASTParser</li>
* <li>{@link #PROTECT} - indicates node is protected from further modification</li>
* <li>{@link #RECOVERED} - indicates node or a part of this node is recovered from source that
* contains a syntax error</li>
* </ul>
* Other bit positions are reserved for future use.
* </p>
* <p>
* Note that the flags are <em>not</em> considered a structural property of the node, and can be
* changed even if the node is marked as protected.
* </p>
*
* @param flags the bitwise-or of individual flags
* @see #getFlags()
*/
public final void setFlags(int flags) {
this.ast.modifying();
int old= this.typeAndFlags & 0xFFFF0000;
this.typeAndFlags= old | (flags & 0xFFFF);
}
/**
* Returns an integer value identifying the type of this concrete AST node. The values are small
* positive integers, suitable for use in switch statements.
* <p>
* For each concrete node type there is a unique node type constant (name and value). The unique
* node type constant for a concrete node type such as <code>CastExpression</code> is
* <code>ASTNode.CAST_EXPRESSION</code>.
* </p>
*
* @return one of the node type constants
*/
public final int getNodeType() {
return this.typeAndFlags >>> 16;
}
/**
* Sets the integer value identifying the type of this concrete AST node. The values are small
* positive integers, suitable for use in switch statements.
*
* @param nodeType one of the node type constants
*/
private void setNodeType(int nodeType) {
int old= this.typeAndFlags & 0xFFFF0000;
this.typeAndFlags= old | (nodeType << 16);
}
/**
* Returns an integer value identifying the type of this concrete AST node.
* <p>
* This internal method is implemented in each of the concrete node subclasses.
* </p>
*
* @return one of the node type constants
*/
abstract int getNodeType0();
/**
* The <code>ASTNode</code> implementation of this <code>Object</code> method uses object
* identity (==). Use <code>subtreeMatch</code> to compare two subtrees for equality.
*
* @param obj {@inheritDoc}
* @return {@inheritDoc}
* @see #subtreeMatch(ASTMatcher matcher, Object other)
*/
public final boolean equals(Object obj) {
return this == obj; // equivalent to Object.equals
}
/*
* (non-Javadoc)
* This makes it consistent with the fact that a equals methods has been provided.
* @see java.lang.Object#hashCode()
*/
public final int hashCode() {
return super.hashCode();
}
/**
* Returns whether the subtree rooted at the given node matches the given other object as
* decided by the given matcher.
*
* @param matcher the matcher
* @param other the other object, or <code>null</code>
* @return <code>true</code> if the subtree matches, or <code>false</code> if they do not match
*/
public final boolean subtreeMatch(ASTMatcher matcher, Object other) {
return subtreeMatch0(matcher, other);
}
/**
* Returns whether the subtree rooted at the given node matches the given other object as
* decided by the given matcher.
* <p>
* This internal method is implemented in each of the concrete node subclasses.
* </p>
*
* @param matcher the matcher
* @param other the other object, or <code>null</code>
* @return <code>true</code> if the subtree matches, or <code>false</code> if they do not match
*/
abstract boolean subtreeMatch0(ASTMatcher matcher, Object other);
/**
* Returns a deep copy of the subtree of AST nodes rooted at the given node. The resulting nodes
* are owned by the given AST, which may be different from the ASTs of the given node. Even if
* the given node has a parent, the result node will be unparented.
* <p>
* Source range information on the original nodes is automatically copied to the new nodes.
* Client properties (<code>properties</code>) are not carried over.
* </p>
* <p>
* The node's <code>AST</code> and the target <code>AST</code> must support the same API level.
* </p>
*
* @param target the AST that is to own the nodes in the result
* @param node the node to copy, or <code>null</code> if none
* @return the copied node, or <code>null</code> if <code>node</code> is <code>null</code>
*/
public static ASTNode copySubtree(AST target, ASTNode node) {
if (node == null) {
return null;
}
if (target == null) {
throw new IllegalArgumentException();
}
if (target.apiLevel() != node.getAST().apiLevel()) {
throw new UnsupportedOperationException();
}
ASTNode newNode= node.clone(target);
return newNode;
}
/**
* Returns a deep copy of the subtrees of AST nodes rooted at the given list of nodes. The
* resulting nodes are owned by the given AST, which may be different from the ASTs of the nodes
* in the list. Even if the nodes in the list have parents, the nodes in the result will be
* unparented.
* <p>
* Source range information on the original nodes is automatically copied to the new nodes.
* Client properties (<code>properties</code>) are not carried over.
* </p>
*
* @param target the AST that is to own the nodes in the result
* @param nodes the list of nodes to copy (element type: <code>ASTNode</code>)
* @return the list of copied subtrees (element type: <code>ASTNode</code>)
*/
public static List copySubtrees(AST target, List nodes) {
List result= new ArrayList(nodes.size());
for (Iterator it= nodes.iterator(); it.hasNext();) {
ASTNode oldNode= (ASTNode)it.next();
ASTNode newNode= oldNode.clone(target);
result.add(newNode);
}
return result;
}
/**
* Returns a deep copy of the subtree of AST nodes rooted at this node. The resulting nodes are
* owned by the given AST, which may be different from the AST of this node. Even if this node
* has a parent, the result node will be unparented.
* <p>
* This method reports pre- and post-clone events, and dispatches to <code>clone0(AST)</code>
* which is reimplemented in node subclasses.
* </p>
*
* @param target the AST that is to own the nodes in the result
* @return the root node of the copies subtree
*/
final ASTNode clone(AST target) {
this.ast.preCloneNodeEvent(this);
ASTNode c= clone0(target);
this.ast.postCloneNodeEvent(this, c);
return c;
}
/**
* Returns a deep copy of the subtree of AST nodes rooted at this node. The resulting nodes are
* owned by the given AST, which may be different from the AST of this node. Even if this node
* has a parent, the result node will be unparented.
* <p>
* This method must be implemented in subclasses.
* </p>
* <p>
* This method does not report pre- and post-clone events. All callers should instead call
* <code>clone(AST)</code> to ensure that pre- and post-clone events are reported.
* </p>
* <p>
* N.B. This method is package-private, so that the implementations of this method in each of
* the concrete AST node types do not clutter up the API doc.
* </p>
*
* @param target the AST that is to own the nodes in the result
* @return the root node of the copies subtree
*/
abstract ASTNode clone0(AST target);
/**
* Accepts the given visitor on a visit of the current node.
*
* @param visitor the visitor object
* @exception IllegalArgumentException if the visitor is null
*/
public final void accept(ASTVisitor visitor) {
if (visitor == null) {
throw new IllegalArgumentException();
}
// begin with the generic pre-visit
if (visitor.preVisit2(this)) {
// dynamic dispatch to internal method for type-specific visit/endVisit
accept0(visitor);
}
// end with the generic post-visit
visitor.postVisit(this);
}
/**
* Accepts the given visitor on a type-specific visit of the current node. This method must be
* implemented in all concrete AST node types.
* <p>
* General template for implementation on each concrete ASTNode class:
*
* <pre>
* <code>
* boolean visitChildren = visitor.visit(this);
* if (visitChildren) {
* // visit children in normal left to right reading order
* acceptChild(visitor, getProperty1());
* acceptChildren(visitor, rawListProperty);
* acceptChild(visitor, getProperty2());
* }
* visitor.endVisit(this);
* </code>
* </pre>
*
* Note that the caller (<code>accept</code>) take cares of invoking
* <code>visitor.preVisit(this)</code> and <code>visitor.postVisit(this)</code>.
* </p>
*
* @param visitor the visitor object
*/
abstract void accept0(ASTVisitor visitor);
/**
* Accepts the given visitor on a visit of the current node.
* <p>
* This method should be used by the concrete implementations of <code>accept0</code> to
* traverse optional properties. Equivalent to <code>child.accept(visitor)</code> if
* <code>child</code> is not <code>null</code>.
* </p>
*
* @param visitor the visitor object
* @param child the child AST node to dispatch too, or <code>null</code> if none
*/
final void acceptChild(ASTVisitor visitor, ASTNode child) {
if (child == null) {
return;
}
child.accept(visitor);
}
/**
* Accepts the given visitor on a visit of the given live list of child nodes.
* <p>
* This method must be used by the concrete implementations of <code>accept</code> to traverse
* list-values properties; it encapsulates the proper handling of on-the-fly changes to the
* list.
* </p>
*
* @param visitor the visitor object
* @param children the child AST node to dispatch too, or <code>null</code> if none
*/
final void acceptChildren(ASTVisitor visitor, ASTNode.NodeList children) {
// use a cursor to keep track of where we are up to
// (the list may be changing under foot)
NodeList.Cursor cursor= children.newCursor();
try {
while (cursor.hasNext()) {
ASTNode child= (ASTNode)cursor.next();
child.accept(visitor);
}
} finally {
children.releaseCursor(cursor);
}
}
/**
* Returns the character index into the original source file indicating where the source
* fragment corresponding to this node begins.
* <p>
* The parser supplies useful well-defined source ranges to the nodes it creates. See
* {@link ASTParser#setKind(int)} for details on precisely where source ranges begin and end.
* </p>
*
* @return the 0-based character index, or <code>-1</code> if no source position information is
* recorded for this node
* @see #getLength()
* @see ASTParser
*/
public final int getStartPosition() {
return this.startPosition;
}
/**
* Returns the length in characters of the original source file indicating where the source
* fragment corresponding to this node ends.
* <p>
* The parser supplies useful well-defined source ranges to the nodes it creates. See
* {@link ASTParser#setKind(int)} methods for details on precisely where source ranges begin and
* end.
* </p>
*
* @return a (possibly 0) length, or <code>0</code> if no source position information is
* recorded for this node
* @see #getStartPosition()
* @see ASTParser
*/
public final int getLength() {
return this.length;
}
/**
* Sets the source range of the original source file where the source fragment corresponding to
* this node was found.
* <p>
* See {@link ASTParser#setKind(int)} for details on precisely where source ranges are supposed
* to begin and end.
* </p>
*
* @param startPosition a 0-based character index, or <code>-1</code> if no source position
* information is available for this node
* @param length a (possibly 0) length, or <code>0</code> if no source position information is
* recorded for this node
* @see #getStartPosition()
* @see #getLength()
* @see ASTParser
*/
public final void setSourceRange(int startPosition, int length) {
if (startPosition >= 0 && length < 0) {
throw new IllegalArgumentException();
}
if (startPosition < 0 && length != 0) {
throw new IllegalArgumentException();
}
// source positions are not considered a structural property
// but we protect them nevertheless
checkModifiable();
this.startPosition= startPosition;
this.length= length;
}
/**
* Returns a string representation of this node suitable for debugging purposes only.
*
* @return a debug string
*/
public final String toString() {
StringBuffer buffer= new StringBuffer();
int p= buffer.length();
try {
appendDebugString(buffer);
} catch (RuntimeException e) {
// since debugger sometimes call toString methods, problems can easily happen when
// toString is called on an instance that is being initialized
buffer.setLength(p);
buffer.append("!"); //$NON-NLS-1$
buffer.append(standardToString());
}
return buffer.toString();
}
/**
* Returns the string representation of this node produced by the standard
* <code>Object.toString</code> method.
*
* @return a debug string
*/
final String standardToString() {
return super.toString();
}
/**
* Appends a debug representation of this node to the given string buffer.
* <p>
* The <code>ASTNode</code> implementation of this method prints out the entire subtree.
* Subclasses may override to provide a more succinct representation.
* </p>
*
* @param buffer the string buffer to append to
*/
void appendDebugString(StringBuffer buffer) {
// print the subtree by default
appendPrintString(buffer);
}
/**
* Appends a standard Java source code representation of this subtree to the given string
* buffer.
*
* @param buffer the string buffer to append to
*/
final void appendPrintString(StringBuffer buffer) {
NaiveASTFlattener printer= new NaiveASTFlattener();
accept(printer);
buffer.append(printer.getResult());
}
/**
* Estimate of size of an object header in bytes.
*/
static final int HEADERS= 12;
/**
* Approximate base size of an AST node instance in bytes, including object header and instance
* fields. That is, HEADERS + (# instance vars in ASTNode)*4.
*/
static final int BASE_NODE_SIZE= HEADERS + 7 * 4;
/**
* Returns an estimate of the memory footprint, in bytes, of the given string.
*
* @param string the string to measure, or <code>null</code>
* @return the size of this string object in bytes, or 0 if the string is <code>null</code>
* @since 3.0
*/
static int stringSize(String string) {
int size= 0;
if (string != null) {
// Strings usually have 4 instance fields, one of which is a char[]
size+= HEADERS + 4 * 4;
// char[] has 2 bytes per character
size+= HEADERS + 2 * string.length();
}
return size;
}
/**
* Returns an estimate of the memory footprint in bytes of the entire subtree rooted at this
* node.
*
* @return the size of this subtree in bytes
*/
public final int subtreeBytes() {
return treeSize();
}
/**
* Returns an estimate of the memory footprint in bytes of the entire subtree rooted at this
* node.
* <p>
* N.B. This method is package-private, so that the implementations of this method in each of
* the concrete AST node types do not clutter up the API doc.
* </p>
*
* @return the size of this subtree in bytes
*/
abstract int treeSize();
/**
* Returns an estimate of the memory footprint of this node in bytes. The estimate does not
* include the space occupied by child nodes.
*
* @return the size of this node in bytes
*/
abstract int memSize();
}