edu.mit.ai.psg.jeva
Class JNEAssignmentExpression

java.lang.Object
  |
  +--edu.mit.ai.psg.jeva.SimpleNode
        |
        +--edu.mit.ai.psg.jeva.JevaNode
              |
              +--edu.mit.ai.psg.jeva.ExpressionNode
                    |
                    +--edu.mit.ai.psg.jeva.JNEAssignmentExpression

public class JNEAssignmentExpression
extends ExpressionNode
implements JevaParserConstants

Jeva parse Nodes for all assignment Expressions (=, +=, *=, etc.) [JavaLangSpec1.0 sec 15.25]. Note that assignment conversion is less powerful than casting conversion, so "int x=0; x = 1.0;" is not ok, but "int x=0; x += 1.0;" is ok.


Fields inherited from class edu.mit.ai.psg.jeva.SimpleNode
children, id, parent
 
Fields inherited from interface edu.mit.ai.psg.jeva.JevaParserConstants
_DEFAULT, ABSTRACT, ANDASSIGN, ASSIGN, BANG, BIT_AND, BIT_OR, BOOLEAN, BREAK, BYTE, CASE, CATCH, CHAR, CHARACTER_LITERAL, CLASS, COLON, COMMA, CONST, CONTINUE, DECIMAL_LITERAL, DECR, DEFAULT, DIGIT, DO, DOT, DOUBLE, ELSE, EOF, EQ, EXPONENT, EXTENDS, FALSE, FINAL, FINALLY, FLOAT, FLOATING_POINT_LITERAL, FOR, FORMAL_COMMENT, GE, GOTO, GT, HEX_LITERAL, HOOK, IDENTIFIER, IF, IMPLEMENTS, IMPORT, INCR, INSTANCEOF, INT, INTEGER_LITERAL, INTERFACE, LBRACE, LBRACKET, LE, LETTER, LONG, LPAREN, LSHIFT, LSHIFTASSIGN, LT, MINUS, MINUSASSIGN, MULTI_LINE_COMMENT, NATIVE, NE, NEW, NULL, OCTAL_LITERAL, ORASSIGN, PACKAGE, PLUS, PLUSASSIGN, PRIVATE, PROTECTED, PUBLIC, RBRACE, RBRACKET, REM, REMASSIGN, RETURN, RPAREN, RSIGNEDSHIFT, RSIGNEDSHIFTASSIGN, RUNSIGNEDSHIFT, RUNSIGNEDSHIFTASSIGN, SC_AND, SC_OR, SEMICOLON, SHORT, SINGLE_LINE_COMMENT, SLASH, SLASHASSIGN, STAR, STARASSIGN, STATIC, STRING_LITERAL, SUPER, SWITCH, SYNCHRONIZED, THIS, THROW, THROWS, TILDE, tokenImage, TRANSIENT, TRUE, TRY, VOID, VOLATILE, WHILE, WHITE_SPACE, XOR, XORASSIGN
 
Method Summary
 boolean computeIsConstant(IEnv env)
          Compute whether this expression is a constant (nodes should not call this method directly).
 IClass computeType(IEnv env)
          Type is the type of the assignment target
 Object eval(IEnv env)
          Eval must evaluate left side target before right side expression [JavaLangSpec1.0 sec 15.25] So left side returns a thunk to do the store.
 JNEAssignmentOperator getAssignmentOperatorNode()
           
 IExpressionNode getSourceExpressionNode()
           
 IExpressionStoreNode getTargetStoreNode()
           
 Object jjtAccept(IJevaVisitor visitor, Object data)
          Accept a visitor.
 
Methods inherited from class edu.mit.ai.psg.jeva.ExpressionNode
getType, getType, getValue, isConstant
 
Methods inherited from class edu.mit.ai.psg.jeva.JevaNode
checkInsertionPoint, find2ndTokenBeforeEndBody, findChildIndex, findPrecedingToken, findTokenBeforeChild, findTokenBeforeChild, findTokenBeforeEnd, getBeginToken, getEndToken, insertChildTokens, insertNewChildAfter, insertNewChildAt, insertNewChildBefore, jnGetChild, jnGetParent, notVerified, print, print, printSpecialTokens, printToken, printToString, printToString, removeChild, removeChildTokens, replaceChild, replaceChild, setBeginToken, setEndToken, shouldNotHappen, shouldNotHappen, shouldNotHappen, updateEndTokens, updateEndTokensPriorChild, updateEndTokensPriorNode, updateEndTokensPriorNode
 
Methods inherited from class edu.mit.ai.psg.jeva.SimpleNode
dump, jjtAddChild, jjtClose, jjtGetChild, jjtGetNumChildren, jjtGetParent, jjtOpen, jjtSetParent, toString, toString
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Method Detail

jjtAccept

public Object jjtAccept(IJevaVisitor visitor,
                        Object data)
Description copied from interface: IJevaNode
Accept a visitor. For visitor design pattern: jjtAccept must simply
  return visitor.visit(this, data);  
which dispatches on the type of this to appropriate method of visitor
Overrides:
jjtAccept in class JevaNode

getTargetStoreNode

public IExpressionStoreNode getTargetStoreNode()

getAssignmentOperatorNode

public JNEAssignmentOperator getAssignmentOperatorNode()

getSourceExpressionNode

public IExpressionNode getSourceExpressionNode()

computeType

public IClass computeType(IEnv env)
                   throws VerifyingException
Type is the type of the assignment target
Overrides:
computeType in class ExpressionNode
Tags copied from class: ExpressionNode
Parameters:
env - environment of name bindings, etc.
Returns:
the IClass of the static type.
Throws:
VerifyingException - if expression is illegal
See Also:
EvalMethods.getType(IExpressionNode, IEnv)

computeIsConstant

public boolean computeIsConstant(IEnv env)
Description copied from class: ExpressionNode
Compute whether this expression is a constant (nodes should not call this method directly). Called by the isConstant method.
Overrides:
computeIsConstant in class ExpressionNode
Tags copied from class: ExpressionNode
Parameters:
env - environment of name bindings, etc.
Throws:
VerifyingException - if expression is illegal.
See Also:
ExpressionNode.isConstant(edu.mit.ai.psg.jeva.IEnv), EvalMethods.isConstant(IExpressionNode, IEnv)

eval

public Object eval(IEnv env)
            throws ThrowException
Eval must evaluate left side target before right side expression [JavaLangSpec1.0 sec 15.25] So left side returns a thunk to do the store.
Overrides:
eval in class ExpressionNode
Tags copied from class: ExpressionNode
Parameters:
env - environment of name bindings, etc.
Throws:
ThrowException - if abruptly completed with an exception
See Also:
ExpressionNode.getValue(edu.mit.ai.psg.jeva.IEnv), EvalMethods.eval(IExpressionNode, IEnv)

Copyright (c) 1996-1999
Massachusetts Institute of Technology

Feedback: jeva-feedback@ai.mit.edu