1   /*
    2    * Copyright (c) 2005, 2011, Oracle and/or its affiliates. All rights reserved.
    3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
    4    *
    5    * This code is free software; you can redistribute it and/or modify it
    6    * under the terms of the GNU General Public License version 2 only, as
    7    * published by the Free Software Foundation.  Oracle designates this
    8    * particular file as subject to the "Classpath" exception as provided
    9    * by Oracle in the LICENSE file that accompanied this code.
   10    *
   11    * This code is distributed in the hope that it will be useful, but WITHOUT
   12    * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   13    * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   14    * version 2 for more details (a copy is included in the LICENSE file that
   15    * accompanied this code).
   16    *
   17    * You should have received a copy of the GNU General Public License version
   18    * 2 along with this work; if not, write to the Free Software Foundation,
   19    * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   20    *
   21    * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   22    * or visit www.oracle.com if you need additional information or have any
   23    * questions.
   24    */
   25   
   26   package com.sun.source.tree;
   27   
   28   /**
   29    * A visitor of trees, in the style of the visitor design pattern.
   30    * Classes implementing this interface are used to operate
   31    * on a tree when the kind of tree is unknown at compile time.
   32    * When a visitor is passed to an tree's {@link Tree#accept
   33    * accept} method, the <tt>visit<i>XYZ</i></tt> method most applicable
   34    * to that tree is invoked.
   35    *
   36    * <p> Classes implementing this interface may or may not throw a
   37    * {@code NullPointerException} if the additional parameter {@code p}
   38    * is {@code null}; see documentation of the implementing class for
   39    * details.
   40    *
   41    * <p> <b>WARNING:</b> It is possible that methods will be added to
   42    * this interface to accommodate new, currently unknown, language
   43    * structures added to future versions of the Java&trade; programming
   44    * language.  Therefore, visitor classes directly implementing this
   45    * interface may be source incompatible with future versions of the
   46    * platform.
   47    *
   48    * @param <R> the return type of this visitor's methods.  Use {@link
   49    *            Void} for visitors that do not need to return results.
   50    * @param <P> the type of the additional parameter to this visitor's
   51    *            methods.  Use {@code Void} for visitors that do not need an
   52    *            additional parameter.
   53    *
   54    * @author Peter von der Ah&eacute;
   55    * @author Jonathan Gibbons
   56    *
   57    * @since 1.6
   58    */
   59   public interface TreeVisitor<R,P> {
   60       R visitAnnotation(AnnotationTree node, P p);
   61       R visitMethodInvocation(MethodInvocationTree node, P p);
   62       R visitAssert(AssertTree node, P p);
   63       R visitAssignment(AssignmentTree node, P p);
   64       R visitCompoundAssignment(CompoundAssignmentTree node, P p);
   65       R visitBinary(BinaryTree node, P p);
   66       R visitBlock(BlockTree node, P p);
   67       R visitBreak(BreakTree node, P p);
   68       R visitCase(CaseTree node, P p);
   69       R visitCatch(CatchTree node, P p);
   70       R visitClass(ClassTree node, P p);
   71       R visitConditionalExpression(ConditionalExpressionTree node, P p);
   72       R visitContinue(ContinueTree node, P p);
   73       R visitDoWhileLoop(DoWhileLoopTree node, P p);
   74       R visitErroneous(ErroneousTree node, P p);
   75       R visitExpressionStatement(ExpressionStatementTree node, P p);
   76       R visitEnhancedForLoop(EnhancedForLoopTree node, P p);
   77       R visitForLoop(ForLoopTree node, P p);
   78       R visitIdentifier(IdentifierTree node, P p);
   79       R visitIf(IfTree node, P p);
   80       R visitImport(ImportTree node, P p);
   81       R visitArrayAccess(ArrayAccessTree node, P p);
   82       R visitLabeledStatement(LabeledStatementTree node, P p);
   83       R visitLiteral(LiteralTree node, P p);
   84       R visitMethod(MethodTree node, P p);
   85       R visitModifiers(ModifiersTree node, P p);
   86       R visitNewArray(NewArrayTree node, P p);
   87       R visitNewClass(NewClassTree node, P p);
   88       R visitParenthesized(ParenthesizedTree node, P p);
   89       R visitReturn(ReturnTree node, P p);
   90       R visitMemberSelect(MemberSelectTree node, P p);
   91       R visitEmptyStatement(EmptyStatementTree node, P p);
   92       R visitSwitch(SwitchTree node, P p);
   93       R visitSynchronized(SynchronizedTree node, P p);
   94       R visitThrow(ThrowTree node, P p);
   95       R visitCompilationUnit(CompilationUnitTree node, P p);
   96       R visitTry(TryTree node, P p);
   97       R visitParameterizedType(ParameterizedTypeTree node, P p);
   98       R visitUnionType(UnionTypeTree node, P p);
   99       R visitArrayType(ArrayTypeTree node, P p);
  100       R visitTypeCast(TypeCastTree node, P p);
  101       R visitPrimitiveType(PrimitiveTypeTree node, P p);
  102       R visitTypeParameter(TypeParameterTree node, P p);
  103       R visitInstanceOf(InstanceOfTree node, P p);
  104       R visitUnary(UnaryTree node, P p);
  105       R visitVariable(VariableTree node, P p);
  106       R visitWhileLoop(WhileLoopTree node, P p);
  107       R visitWildcard(WildcardTree node, P p);
  108       R visitOther(Tree node, P p);
  109   }