content: /*
   * Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   */
  
  package openjdk.tools.javac.tree;
  
  import openjdk.tools.javac.util.*;
  import openjdk.tools.javac.tree.JCTree.*;
  
  /** A subclass of Tree.Visitor, this class defines
   *  a general tree translator pattern. Translation proceeds recursively in
   *  left-to-right order down a tree, constructing translated nodes by
   *  overwriting existing ones. There is one visitor method in this class
   *  for every possible kind of tree node.  To obtain a specific
   *  translator, it suffices to override those visitor methods which
   *  do some interesting work. The translator class itself takes care of all
   *  navigational aspects.
   *
   *  <p><b>This is NOT part of any supported API.
   *  If you write code that depends on this, you do so at your own risk.
   *  This code and its internal interfaces are subject to change or
   *  deletion without notice.</b>
   */
  public class TreeTranslator extends JCTree.Visitor {
  
      /** Visitor result field: a tree
       */
      protected JCTree result;
  
      /** Visitor method: Translate a single node.
       */
      @SuppressWarnings("unchecked")
      public <T extends JCTree> T translate(T tree) {
          if (tree == null) {
              return null;
          } else {
              tree.accept(this);
              JCTree tmpResult = this.result;
              this.result = null;
              return (T)tmpResult; // XXX cast
          }
      }
  
      /** Visitor method: translate a list of nodes.
       */
      public <T extends JCTree> List<T> translate(List<T> trees) {
          if (trees == null) return null;
          for (List<T> l = trees; l.nonEmpty(); l = l.tail)
              l.head = translate(l.head);
          return trees;
      }
  
      /**  Visitor method: translate a list of variable definitions.
       */
      public List<JCVariableDecl> translateVarDefs(List<JCVariableDecl> trees) {
          for (List<JCVariableDecl> l = trees; l.nonEmpty(); l = l.tail)
              l.head = translate(l.head);
          return trees;
      }
  
      /**  Visitor method: translate a list of type parameters.
       */
      public List<JCTypeParameter> translateTypeParams(List<JCTypeParameter> trees) {
          for (List<JCTypeParameter> l = trees; l.nonEmpty(); l = l.tail)
              l.head = translate(l.head);
          return trees;
      }
  
      /**  Visitor method: translate a list of case parts of switch statements.
       */
      public List<JCCase> translateCases(List<JCCase> trees) {
          for (List<JCCase> l = trees; l.nonEmpty(); l = l.tail)
              l.head = translate(l.head);
          return trees;
      }
  
      /**  Visitor method: translate a list of catch clauses in try statements.
       */
      public List<JCCatch> translateCatchers(List<JCCatch> trees) {
          for (List<JCCatch> l = trees; l.nonEmpty(); l = l.tail)
              l.head = translate(l.head);
          return trees;
      }
  
      /**  Visitor method: translate a list of catch clauses in try statements.
       */
      public List<JCAnnotation> translateAnnotations(List<JCAnnotation> trees) {
          for (List<JCAnnotation> l = trees; l.nonEmpty(); l = l.tail)
              l.head = translate(l.head);
          return trees;
      }
  
  /* ***************************************************************************
   * Visitor methods
   ****************************************************************************/
  
      public void visitTopLevel(JCCompilationUnit tree) {
          tree.defs = translate(tree.defs);
          result = tree;
      }
  
      public void visitPackageDef(JCPackageDecl tree) {
          tree.annotations = translate(tree.annotations);
          tree.pid = translate(tree.pid);
          result = tree;
      }
  
      public void visitImport(JCImport tree) {
          tree.qualid = translate(tree.qualid);
          result = tree;
      }
  
      public void visitClassDef(JCClassDecl tree) {
          tree.mods = translate(tree.mods);
          tree.typarams = translateTypeParams(tree.typarams);
          tree.extending = translate(tree.extending);
          tree.implementing = translate(tree.implementing);
          tree.defs = translate(tree.defs);
          result = tree;
      }
  
      public void visitMethodDef(JCMethodDecl tree) {
          tree.mods = translate(tree.mods);
          tree.restype = translate(tree.restype);
          tree.typarams = translateTypeParams(tree.typarams);
          tree.recvparam = translate(tree.recvparam);
          tree.params = translateVarDefs(tree.params);
          tree.thrown = translate(tree.thrown);
          tree.body = translate(tree.body);
          result = tree;
      }
  
      public void visitVarDef(JCVariableDecl tree) {
          tree.mods = translate(tree.mods);
          tree.nameexpr = translate(tree.nameexpr);
          tree.vartype = translate(tree.vartype);
          tree.init = translate(tree.init);
          result = tree;
      }
  
      public void visitSkip(JCSkip tree) {
          result = tree;
      }
  
      public void visitBlock(JCBlock tree) {
          tree.stats = translate(tree.stats);
          result = tree;
      }
  
      public void visitDoLoop(JCDoWhileLoop tree) {
          tree.body = translate(tree.body);
          tree.cond = translate(tree.cond);
          result = tree;
      }
  
      public void visitWhileLoop(JCWhileLoop tree) {
          tree.cond = translate(tree.cond);
          tree.body = translate(tree.body);
          result = tree;
      }
  
      public void visitForLoop(JCForLoop tree) {
          tree.init = translate(tree.init);
          tree.cond = translate(tree.cond);
          tree.step = translate(tree.step);
          tree.body = translate(tree.body);
          result = tree;
      }
  
      public void visitForeachLoop(JCEnhancedForLoop tree) {
          tree.var = translate(tree.var);
          tree.expr = translate(tree.expr);
          tree.body = translate(tree.body);
          result = tree;
      }
  
      public void visitLabelled(JCLabeledStatement tree) {
          tree.body = translate(tree.body);
          result = tree;
      }
  
      public void visitSwitch(JCSwitch tree) {
          tree.selector = translate(tree.selector);
          tree.cases = translateCases(tree.cases);
          result = tree;
      }
  
      public void visitCase(JCCase tree) {
          tree.labels = translate(tree.labels);
          tree.stats = translate(tree.stats);
          result = tree;
      }
  
      public void visitSwitchExpression(JCSwitchExpression tree) {
          tree.selector = translate(tree.selector);
          tree.cases = translateCases(tree.cases);
          result = tree;
      }
  
      public void visitSynchronized(JCSynchronized tree) {
          tree.lock = translate(tree.lock);
          tree.body = translate(tree.body);
          result = tree;
      }
  
      public void visitTry(JCTry tree) {
          tree.resources = translate(tree.resources);
          tree.body = translate(tree.body);
          tree.catchers = translateCatchers(tree.catchers);
          tree.finalizer = translate(tree.finalizer);
          result = tree;
      }
  
      public void visitCatch(JCCatch tree) {
          tree.param = translate(tree.param);
          tree.body = translate(tree.body);
          result = tree;
      }
  
      public void visitConditional(JCConditional tree) {
          tree.cond = translate(tree.cond);
          tree.truepart = translate(tree.truepart);
          tree.falsepart = translate(tree.falsepart);
          result = tree;
      }
  
      public void visitIf(JCIf tree) {
          tree.cond = translate(tree.cond);
          tree.thenpart = translate(tree.thenpart);
          tree.elsepart = translate(tree.elsepart);
          result = tree;
      }
  
      public void visitExec(JCExpressionStatement tree) {
          tree.expr = translate(tree.expr);
          result = tree;
      }
  
      public void visitBreak(JCBreak tree) {
          result = tree;
      }
  
      public void visitYield(JCYield tree) {
          tree.value = translate(tree.value);
          result = tree;
      }
  
      public void visitContinue(JCContinue tree) {
          result = tree;
      }
  
      public void visitReturn(JCReturn tree) {
          tree.expr = translate(tree.expr);
          result = tree;
      }
  
      public void visitThrow(JCThrow tree) {
          tree.expr = translate(tree.expr);
          result = tree;
      }
  
      public void visitAssert(JCAssert tree) {
          tree.cond = translate(tree.cond);
          tree.detail = translate(tree.detail);
          result = tree;
      }
  
      public void visitApply(JCMethodInvocation tree) {
          tree.meth = translate(tree.meth);
          tree.args = translate(tree.args);
          result = tree;
      }
  
      public void visitNewClass(JCNewClass tree) {
          tree.encl = translate(tree.encl);
          tree.clazz = translate(tree.clazz);
          tree.args = translate(tree.args);
          tree.def = translate(tree.def);
          result = tree;
      }
  
      public void visitLambda(JCLambda tree) {
          tree.params = translate(tree.params);
          tree.body = translate(tree.body);
          result = tree;
      }
  
      public void visitNewArray(JCNewArray tree) {
          tree.annotations = translate(tree.annotations);
          List<List<JCAnnotation>> dimAnnos = List.nil();
          for (List<JCAnnotation> origDimAnnos : tree.dimAnnotations)
              dimAnnos = dimAnnos.append(translate(origDimAnnos));
          tree.dimAnnotations = dimAnnos;
          tree.elemtype = translate(tree.elemtype);
          tree.dims = translate(tree.dims);
          tree.elems = translate(tree.elems);
          result = tree;
      }
  
      public void visitParens(JCParens tree) {
          tree.expr = translate(tree.expr);
          result = tree;
      }
  
      public void visitAssign(JCAssign tree) {
          tree.lhs = translate(tree.lhs);
          tree.rhs = translate(tree.rhs);
          result = tree;
      }
  
      public void visitAssignop(JCAssignOp tree) {
          tree.lhs = translate(tree.lhs);
          tree.rhs = translate(tree.rhs);
          result = tree;
      }
  
      public void visitUnary(JCUnary tree) {
          tree.arg = translate(tree.arg);
          result = tree;
      }
  
      public void visitBinary(JCBinary tree) {
          tree.lhs = translate(tree.lhs);
          tree.rhs = translate(tree.rhs);
          result = tree;
      }
  
      public void visitTypeCast(JCTypeCast tree) {
          tree.clazz = translate(tree.clazz);
          tree.expr = translate(tree.expr);
          result = tree;
      }
  
      public void visitTypeTest(JCInstanceOf tree) {
          tree.expr = translate(tree.expr);
          tree.pattern = translate(tree.pattern);
          result = tree;
      }
  
      public void visitBindingPattern(JCBindingPattern tree) {
          tree.var = translate(tree.var);
          result = tree;
      }
  
      @Override
      public void visitDefaultCaseLabel(JCDefaultCaseLabel tree) {
          result = tree;
      }
  
      @Override
      public void visitParenthesizedPattern(JCParenthesizedPattern tree) {
          tree.pattern = translate(tree.pattern);
          result = tree;
      }
  
      @Override
      public void visitGuardPattern(JCGuardPattern tree) {
          tree.patt = translate(tree.patt);
          tree.expr = translate(tree.expr);
          result = tree;
      }
  
      public void visitIndexed(JCArrayAccess tree) {
          tree.indexed = translate(tree.indexed);
          tree.index = translate(tree.index);
          result = tree;
      }
  
      public void visitSelect(JCFieldAccess tree) {
          tree.selected = translate(tree.selected);
          result = tree;
      }
  
      public void visitReference(JCMemberReference tree) {
          tree.expr = translate(tree.expr);
          result = tree;
      }
  
      public void visitIdent(JCIdent tree) {
          result = tree;
      }
  
      public void visitLiteral(JCLiteral tree) {
          result = tree;
      }
  
      public void visitTypeIdent(JCPrimitiveTypeTree tree) {
          result = tree;
      }
  
      public void visitTypeArray(JCArrayTypeTree tree) {
          tree.elemtype = translate(tree.elemtype);
          result = tree;
      }
  
      public void visitTypeApply(JCTypeApply tree) {
          tree.clazz = translate(tree.clazz);
          tree.arguments = translate(tree.arguments);
          result = tree;
      }
  
      public void visitTypeUnion(JCTypeUnion tree) {
          tree.alternatives = translate(tree.alternatives);
          result = tree;
      }
  
      public void visitTypeIntersection(JCTypeIntersection tree) {
          tree.bounds = translate(tree.bounds);
          result = tree;
      }
  
      public void visitTypeParameter(JCTypeParameter tree) {
          tree.annotations = translate(tree.annotations);
          tree.bounds = translate(tree.bounds);
          result = tree;
      }
  
      @Override
      public void visitWildcard(JCWildcard tree) {
          tree.kind = translate(tree.kind);
          tree.inner = translate(tree.inner);
          result = tree;
      }
  
      @Override
      public void visitTypeBoundKind(TypeBoundKind tree) {
          result = tree;
      }
  
      public void visitErroneous(JCErroneous tree) {
          result = tree;
      }
  
      public void visitLetExpr(LetExpr tree) {
          tree.defs = translate(tree.defs);
          tree.expr = translate(tree.expr);
          result = tree;
      }
  
      public void visitModifiers(JCModifiers tree) {
          tree.annotations = translateAnnotations(tree.annotations);
          result = tree;
      }
  
      public void visitAnnotation(JCAnnotation tree) {
          tree.annotationType = translate(tree.annotationType);
          tree.args = translate(tree.args);
          result = tree;
      }
  
      public void visitAnnotatedType(JCAnnotatedType tree) {
          tree.annotations = translate(tree.annotations);
          tree.underlyingType = translate(tree.underlyingType);
          result = tree;
      }
  
      public void visitTree(JCTree tree) {
          throw new AssertionError(tree);
      }
  }
  