Java Code Examples for com.sun.tools.javac.tree.JCTree#JCUnary

/**
 * strip out enclosing parentheses, type casts and Nullchk operators.
 *
 * @param expr a potentially parenthesised expression.
 * @return the same expression without parentheses.
 */
private static ExpressionTree stripParensAndCasts(ExpressionTree expr) {
  boolean someChange = true;
  while (someChange) {
    someChange = false;
    if (expr.getKind().equals(PARENTHESIZED)) {
      expr = ((ParenthesizedTree) expr).getExpression();
      someChange = true;
    }
    if (expr.getKind().equals(TYPE_CAST)) {
      expr = ((TypeCastTree) expr).getExpression();
      someChange = true;
    }

    // Strips Nullchk operator
    if (expr.getKind().equals(OTHER) && expr instanceof JCTree.JCUnary) {
      expr = ((JCTree.JCUnary) expr).getExpression();
      someChange = true;
    }
  }
  return expr;
}
 

@Override
public void visitUnary( JCTree.JCUnary tree )
{
  if( !JavacPlugin.instance().isExtensionsEnabled() )
  {
    super.visitUnary( tree );
    return;
  }

  if( handleNegationOverloading( tree ) )
  {
    // Handle negation overloading
    return;
  }

  super.visitUnary( tree );
}
 

default boolean handleNegationOverloading( JCTree.JCUnary tree )
{
  if( tree.getTag() != Tag.NEG )
  {
    return false;
  }

  // Attribute arguments
  ReflectUtil.LiveMethodRef checkNonVoid = ReflectUtil.method( chk(), "checkNonVoid", JCDiagnostic.DiagnosticPosition.class, Type.class );
  ReflectUtil.LiveMethodRef attribExpr = ReflectUtil.method( this, "attribExpr", JCTree.class, Env.class );
  Type expr = (Type)checkNonVoid.invoke( tree.arg.pos(), attribExpr.invoke( tree.arg, getEnv() ) );

  // Handle operator overloading
  Symbol.MethodSymbol overloadOperator = ManAttr.resolveNegationMethod( types(), tree.getTag(), expr );
  if( overloadOperator != null )
  {
    overloadOperator = new OverloadOperatorSymbol( overloadOperator, false );
    IDynamicJdk.instance().setOperator( tree, (Symbol.OperatorSymbol)overloadOperator );
    Type owntype = overloadOperator.type.isErroneous()
                   ? overloadOperator.type
                   : types().memberType( expr, overloadOperator ).getReturnType();
    setResult( tree, owntype );
    return true;
  }
  return false;
}
 

@Override
public void setOperator( JCTree.JCExpression tree, Symbol.OperatorSymbol operator )
{
  if( tree instanceof JCTree.JCBinary )
  {
    ((JCTree.JCBinary)tree).operator = operator;
  }
  else
  {
    ((JCTree.JCUnary)tree).operator = operator;
  }
}
 

@Override
public void visitUnary( JCTree.JCUnary tree )
{
  super.visitUnary( tree );

  if( _tp.isGenerate() && !shouldProcessForGeneration() )
  {
    // Don't process tree during GENERATE, unless the tree was generated e.g., a bridge method
    return;
  }

  Symbol op = IDynamicJdk.instance().getOperator( tree );
  if( op instanceof OverloadOperatorSymbol ) // handle negation overload
  {
    TreeMaker make = _tp.getTreeMaker();

    // Handle operator overload expressions

    Symbol.MethodSymbol operatorMethod = (Symbol.MethodSymbol)op;
    while( operatorMethod instanceof OverloadOperatorSymbol )
    {
      operatorMethod = ((OverloadOperatorSymbol)operatorMethod).getMethod();
    }

    if( operatorMethod != null )
    {
      JCTree.JCMethodInvocation methodCall;
      JCExpression receiver = tree.getExpression();
      methodCall = make.Apply( List.nil(), make.Select( receiver, operatorMethod ), List.nil() );
      methodCall.setPos( tree.pos );
      methodCall.type = operatorMethod.getReturnType();

      // If methodCall is an extension method, rewrite it accordingly
      Symbol.MethodSymbol extMethod = findExtMethod( methodCall );
      if( extMethod != null )
      {
        // Replace with extension method call
        methodCall = replaceExtCall( methodCall, extMethod );
      }

      result = methodCall;
    }
  }
  else if( isJailbreakReceiver( tree ) )
  {
    Tree.Kind kind = tree.getKind();
    if( kind == Tree.Kind.POSTFIX_INCREMENT || kind == Tree.Kind.POSTFIX_DECREMENT ||
        kind == Tree.Kind.PREFIX_INCREMENT || kind == Tree.Kind.PREFIX_DECREMENT )
    {
      // ++, -- operators not supported with jailbreak access to fields, only direct assignment
      _tp.report( tree, Diagnostic.Kind.ERROR, ExtIssueMsg.MSG_INCREMENT_OP_NOT_ALLOWED_REFLECTION.get() );
      Types types = Types.instance( ((BasicJavacTask)_tp.getJavacTask()).getContext() );
      tree.type = types.createErrorType( tree.type );
    }
    result = tree;
  }
  else
  {
    result = tree;
  }
}
 

private JCTree replaceWithReflection( JCTree.JCFieldAccess tree )
{
  TreeMaker make = _tp.getTreeMaker();
  JavacElements javacElems = _tp.getElementUtil();

  boolean isStatic = tree.sym.getModifiers().contains( javax.lang.model.element.Modifier.STATIC );
  if( tree.sym instanceof Symbol.MethodSymbol )
  {
    return tree;
  }

  Tree parent = _tp.getParent( tree );
  if( parent instanceof JCTree.JCAssign && ((JCTree.JCAssign)parent).lhs == tree ||
      parent instanceof JCTree.JCAssignOp && ((JCTree.JCAssignOp)parent).lhs == tree )
  {
    // handled in visitAssign() or visitAssignOp()
    return tree;
  }

  if( parent instanceof JCTree.JCUnary && ((JCTree.JCUnary)parent).arg == tree )
  {
    Tree.Kind kind = parent.getKind();

    if( kind != Tree.Kind.UNARY_MINUS && kind != Tree.Kind.UNARY_PLUS &&
        kind != Tree.Kind.LOGICAL_COMPLEMENT && kind != Tree.Kind.BITWISE_COMPLEMENT )
    {
      // supporting -, +, !, ~  not supporting --, ++
      _tp.report( (JCTree)parent, Diagnostic.Kind.ERROR, ExtIssueMsg.MSG_INCREMENT_OP_NOT_ALLOWED_REFLECTION.get() );
      return tree;
    }
  }

  Type type = tree.sym.type;
  if( type instanceof Type.ErrorType )
  {
    // No such field/method
    return tree;
  }

  Symbol.MethodSymbol reflectMethodSym = findFieldAccessReflectUtilMethod( tree, type, isStatic, false );

  ArrayList<JCExpression> newArgs = new ArrayList<>();
  newArgs.add( isStatic ? makeClassExpr( tree, tree.selected.type ) : tree.selected ); // receiver or class
  newArgs.add( make.Literal( tree.sym.flatName().toString() ) ); // field name

  Symbol.ClassSymbol reflectMethodClassSym =
    IDynamicJdk.instance().getTypeElement( _tp.getContext(), _tp.getCompilationUnit(), ReflectionRuntimeMethods.class.getName() );

  JCTree.JCMethodInvocation reflectCall =
    make.Apply( List.nil(),
      memberAccess( make, javacElems, ReflectionRuntimeMethods.class.getName() + "." + reflectMethodSym.flatName().toString() ),
      List.from( newArgs ) );
  reflectCall.setPos( tree.pos );
  reflectCall.type = type;
  JCTree.JCFieldAccess newMethodSelect = (JCTree.JCFieldAccess)reflectCall.getMethodSelect();
  newMethodSelect.sym = reflectMethodSym;
  newMethodSelect.type = reflectMethodSym.type;
  assignTypes( newMethodSelect.selected, reflectMethodClassSym );

  return reflectCall;
}
 

@Override
public Symbol getOperator( JCTree.JCExpression tree )
{
  return tree instanceof JCTree.JCBinary ? ((JCTree.JCBinary)tree).operator : ((JCTree.JCUnary)tree).operator;
}