bsh.BSHAssignment Maven / Gradle / Ivy
The newest version!
/*
* #%L
* The AIBench Shell Plugin
* %%
* Copyright (C) 2006 - 2017 Daniel Glez-Peña and Florentino Fdez-Riverola
* %%
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* This program 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 Lesser Public License for more details.
*
* You should have received a copy of the GNU General Lesser Public
* License along with this program. If not, see
* .
* #L%
*/
/*****************************************************************************
* *
* This file is part of the BeanShell Java Scripting distribution. *
* Documentation and updates may be found at http://www.beanshell.org/ *
* *
* Sun Public License Notice: *
* *
* The contents of this file are subject to the Sun Public License Version *
* 1.0 (the "License"); you may not use this file except in compliance with *
* the License. A copy of the License is available at http://www.sun.com *
* *
* The Original Code is BeanShell. The Initial Developer of the Original *
* Code is Pat Niemeyer. Portions created by Pat Niemeyer are Copyright *
* (C) 2000. All Rights Reserved. *
* *
* GNU Public License Notice: *
* *
* Alternatively, the contents of this file may be used under the terms of *
* the GNU Lesser General Public License (the "LGPL"), in which case the *
* provisions of LGPL are applicable instead of those above. If you wish to *
* allow use of your version of this file only under the terms of the LGPL *
* and not to allow others to use your version of this file under the SPL, *
* indicate your decision by deleting the provisions above and replace *
* them with the notice and other provisions required by the LGPL. If you *
* do not delete the provisions above, a recipient may use your version of *
* this file under either the SPL or the LGPL. *
* *
* Patrick Niemeyer ([email protected]) *
* Author of Learning Java, O'Reilly & Associates *
* http://www.pat.net/~pat/ *
* *
*****************************************************************************/
package bsh;
class BSHAssignment extends SimpleNode implements ParserConstants {
public int operator;
BSHAssignment(int id) {
super(id);
}
public Object eval(CallStack callstack, Interpreter interpreter) throws EvalError {
BSHPrimaryExpression lhsNode = (BSHPrimaryExpression) jjtGetChild(0);
if (lhsNode == null)
throw new InterpreterError("Error, null LHSnode");
boolean strictJava = interpreter.getStrictJava();
LHS lhs = lhsNode.toLHS(callstack, interpreter);
if (lhs == null)
throw new InterpreterError("Error, null LHS");
// For operator-assign operations save the lhs value before
// evaluating
// the rhs. This is correct Java behavior for postfix operations
// e.g. i=1; i+=i++; // should be 2 not 3
Object lhsValue = null;
if (operator != ASSIGN) // assign doesn't need the pre-value
try {
lhsValue = lhs.getValue();
} catch (UtilEvalError e) {
throw e.toEvalError(this, callstack);
}
SimpleNode rhsNode = (SimpleNode) jjtGetChild(1);
Object rhs;
// implement "blocks" foo = { };
// if ( rhsNode instanceof BSHBlock )
// rsh =
// else
rhs = rhsNode.eval(callstack, interpreter);
if (rhs == Primitive.VOID)
throw new EvalError("Void assignment.", this, callstack);
try {
switch (operator) {
case ASSIGN:
return lhs.assign(rhs, strictJava);
case PLUSASSIGN:
return lhs.assign(operation(lhsValue, rhs, PLUS), strictJava);
case MINUSASSIGN:
return lhs.assign(operation(lhsValue, rhs, MINUS), strictJava);
case STARASSIGN:
return lhs.assign(operation(lhsValue, rhs, STAR), strictJava);
case SLASHASSIGN:
return lhs.assign(operation(lhsValue, rhs, SLASH), strictJava);
case ANDASSIGN:
case ANDASSIGNX:
return lhs.assign(operation(lhsValue, rhs, BIT_AND), strictJava);
case ORASSIGN:
case ORASSIGNX:
return lhs.assign(operation(lhsValue, rhs, BIT_OR), strictJava);
case XORASSIGN:
return lhs.assign(operation(lhsValue, rhs, XOR), strictJava);
case MODASSIGN:
return lhs.assign(operation(lhsValue, rhs, MOD), strictJava);
case LSHIFTASSIGN:
case LSHIFTASSIGNX:
return lhs.assign(operation(lhsValue, rhs, LSHIFT), strictJava);
case RSIGNEDSHIFTASSIGN:
case RSIGNEDSHIFTASSIGNX:
return lhs.assign(operation(lhsValue, rhs, RSIGNEDSHIFT), strictJava);
case RUNSIGNEDSHIFTASSIGN:
case RUNSIGNEDSHIFTASSIGNX:
return lhs.assign(operation(lhsValue, rhs, RUNSIGNEDSHIFT), strictJava);
default:
throw new InterpreterError("unimplemented operator in assignment BSH");
}
} catch (UtilEvalError e) {
throw e.toEvalError(this, callstack);
}
}
private Object operation(Object lhs, Object rhs, int kind) throws UtilEvalError {
/*
* Implement String += value; According to the JLS, value may be
* anything. In BeanShell, we'll disallow VOID (undefined)
* values. (or should we map them to the empty string?)
*/
if (lhs instanceof String && rhs != Primitive.VOID) {
if (kind != PLUS)
throw new UtilEvalError("Use of non + operator with String LHS");
return (String) lhs + rhs;
}
if (lhs instanceof Primitive || rhs instanceof Primitive)
if (lhs == Primitive.VOID || rhs == Primitive.VOID)
throw new UtilEvalError("Illegal use of undefined object or 'void' literal");
else if (lhs == Primitive.NULL || rhs == Primitive.NULL)
throw new UtilEvalError("Illegal use of null object or 'null' literal");
if ((lhs instanceof Boolean || lhs instanceof Character || lhs instanceof Number || lhs instanceof Primitive) && (rhs instanceof Boolean || rhs instanceof Character || rhs instanceof Number || rhs instanceof Primitive)) {
return Primitive.binaryOperation(lhs, rhs, kind);
}
throw new UtilEvalError("Non primitive value in operator: " + lhs.getClass() + " " + tokenImage[kind] + " " + rhs.getClass());
}
}
© 2015 - 2024 Weber Informatics LLC | Privacy Policy