ast
Class ASTNode

java.lang.Object
  ast.ASTNode

Direct Known Subclasses:

Class_, Expr, Formal, ListNode, Member, Program, Stmt

public abstract class ASTNode
extends java.lang.Object

The abstract ASTNode class represents a generic AST node. It contains a line number (lineNumber).

AST Summary

ASTNode
An ASTNode is an abstract class that represents a generic node in the AST. It contains a line number indicating where the original source code (represented by the node) was scanned. All nodes in the AST extend ASTNode.

• Program
  Each (correct) Bantam program contains one top-level Program node. A Program node extends ASTNode and contains a list of classes (ClassList).
• ClassList
  A ClassList node extends ListNode and contains a list of Class_ nodes.
• Class_
  A Class_ node represents a class from the Bantam source program. It extends ASTNode and contains a filename (String), a class name (String), a parent name (String), and a list of class members (MemberList).
• Member
  A Member node is an abstract class that represents a class member in a Bantam source program. It is extended by the following:
  • Method
    A Method node represents a method from the Bantam source program. It extends Member and contains a return type (String), a name (String), a list of parameters (ExprList), a list of statements (StmtList), and a return statement (RetnStmt).
  • Field
    A Field node represents a field from the Bantam source program. It extends Member and contains a declaration type (String), a name (String), and an (optional) initialization expression (Expr). For fields without initialization expressions, the initialization expression is null.
• Stmt
  A Stmt node is an abstract class that represents a statement in a Bantam source program. It is extended by the following:
  • ExprStmt
    An ExprStmt represents an expression statement from the Bantam source program. It extends Stmt and contains an expression (Expr).
  • DeclStmt
    A DeclStmt represents a declaration statement from the Bantam source program. It extends Stmt and contains a declaration type (String), a name (String), and a (non-optional) initialization expression (Expr).
  • IfStmt
    An IfStmt represents an if statement from the Bantam source program. It extends Stmt and contains a predicate expression (Expr), a then statement (Stmt), and a else statement (Stmt).
  • WhileStmt
    A WhileStmt represents a while statement from the Bantam source program. It extends Stmt and contains a continuation expression (Expr) and a body statement (Stmt).
  • BlockStmt
    A BlockStmt represents a block statement from the Bantam source program. It contains a list of expressions (ExprList).
• Expr
  An Expr node is an abstract class that represents an expression in a Bantam source program. It is extended by the following:
  • AssignExpr
    An AssignExpr represents an assignment expression from the Bantam source program. It extends Expr and contains an optional reference object (String, which can be null), a lefthand variable name (String), and a righthand expression (Expr).
  • DispatchExpr
    A DispatchExpr represents a dynamic dispatch expression from the Bantam source program. It extends Expr and contains an optional reference object (Expr, which can be null), a method name (String), and a list of arguments (ExprList).
  • CastExpr
    A CastExpr represents an explicit cast expression from the Bantam source program. It extends Expr and contains a target object type (String), an expression to cast (Expr), and a flag (boolean) indicating whether it's an upcast or a downcast.
  • InstanceofExpr
    An InstanceofExpr represents an instanceof operation in a Bantam source program. It extends Expr and contains a expression to test (Expr) and an object type (String).
  • BinaryExpr
    A BinaryExpr is an abstract class that represents all binary expressions where the left and right operands are both expressions (i.e., not casts or instanceof). It extends Expr and contains a lefthand expression (Expr) and a righthand expression (Expr). It is extended by the following:
    • BinaryArithExpr
      A BinaryArithExpr is an abstract class that represents binary arithmetic expressions. It extends BinaryExpr. It is subclassed by the following:
      • BinaryArithPlusExpr
        A BinaryArithPlusExpr represents a addition (`+') expression.
      • BinaryArithMinusExpr
        A BinaryArithMinusExpr represents a subtraction (`-') expression.
      • BinaryArithTimesExpr
        A BinaryArithTimesExpr represents a multiplication (`*') expression.
      • BinaryArithDivideExpr
        A BinaryArithDivideExpr represents a division (`/') expression.
      • BinaryArithModulusExpr
        A BinaryArithModulusExpr represents a modulus (`%') expression.
    • BinaryCompExpr
      A BinaryCompExpr is an abstract class that represents binary comparison expressions. It extends BinaryExpr. It is subclassed by the following:
      • BinaryCompEqExpr
        A BinaryCompEqExpr represents an equivalence (`==') expression.
      • BinaryCompNeExpr
        A BinaryCompNeExpr represents a not equals (`!=') expression.
      • BinaryCompLtExpr
        A BinaryCompLtExpr represents a less than (`<') expression.
      • BinaryCompLeqExpr
        A BinaryCompLeqExpr represents a less than or equal to (`<=') expression.
      • BinaryCompGtExpr
        A BinaryCompGtExpr represents a greater than (`>') expression.
      • BinaryCompGeqExpr
        A BinaryCompGeqExpr represents a greater than or equal to (`>=') expression.
    • BinaryLogicExpr
      A BinaryLogicExpr is an abstract class that represents binary boolean logic expressions. It extends BinaryExpr. It is subclassed by the following:
      • BinaryLogicAndExpr
        A BinaryLogicAndExpr represents a logical AND (`&&') expression.
      • BinaryLogicOrExpr
        A BinaryLogicOrExpr represents a logical OR (`||') expression.
  • UnaryExpr
    A UnaryExpr is an abstract class that represents all unary expressions where the operand is an expression (i.e., not new). It extends Expr and contains an expression operand (Expr). It is extended by the following:
    • UnaryNegExpr
      A UnaryNegExpr represents a unary integer negation (`-') expression.
    • UnaryNotExpr
      A UnaryNotExpr represents a unary boolean complement (`!') expression.
  • ConstExpr
    A ConstExpr is an abstract class that represents all constant expressions. It extends Expr and contains a constant value (String). It is extended by the following:
    • ConstIntExpr
      A ConstIntExpr represents an integer constant (e.g., 12) expression.
    • ConstBooleanExpr
      A ConstBooleanExpr represent a boolean constant (e.g., true, false) expression.
    • ConstStringExpr
      A ConstStringExpr represent a string constant (e.g., ``abc'') expression.
  • VarExpr
    A VarExpr represents a variable reference expression. It extends Expr and contains an optional reference object name (String, which might be null) and a variable name (String).
• ListNode
  A ListNode is an abstract class that represents a generic list of nodes in the AST. All lists of nodes must extend ListNode. These include the following:
  • MemberList
    A MemberList node extends ListNode and contains a list of Member nodes.
  • StmtList
    A StmtList node extends ListNode and contains a list of Stmt nodes.
  • ExprList
    An ExprList node extends ListNode and contains a list of Expr nodes.

Field Summary

protected int	charNum The source starting character number (within line) corresponding to this AST node
protected int	lineNum The source line number corresponding to this AST node
protected java.lang.String	lineStr The source starting line corresponding to this AST node

Constructor Summary

protected

ASTNode(int lineNum) ASTNode constructor

Method Summary

abstract java.lang.Object	accept(Visitor v) Visitor method
int	getLineNum() Get the line number corresponding to this AST node

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

lineNum

protected int lineNum

The source line number corresponding to this AST node

charNum

protected int charNum

The source starting character number (within line) corresponding to this AST node

lineStr

protected java.lang.String lineStr

The source starting line corresponding to this AST node

Constructor Detail

ASTNode

protected ASTNode(int lineNum)

ASTNode constructor

Parameters:

lineNum - source line number corresponding to this AST node

Method Detail

getLineNum

public int getLineNum()

Get the line number corresponding to this AST node

Returns:

line number

accept

public abstract java.lang.Object accept(Visitor v)

Visitor method

Parameters:

v - visitor object

Returns:

result of visiting this node

See Also:

Visitor