/*****************************************************************************
* *
* 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 BSHPrimaryExpression extends SimpleNode
{
BSHPrimaryExpression(int id) { super(id); }
/**
Evaluate to a value object.
*/
public Object eval( CallStack callstack, Interpreter interpreter)
throws EvalError
{
return eval( false, callstack, interpreter );
}
/**
Evaluate to a value object.
*/
public LHS toLHS( CallStack callstack, Interpreter interpreter)
throws EvalError
{
Object obj = eval( true, callstack, interpreter );
if ( ! (obj instanceof LHS) )
throw new EvalError("Can't assign to:", this, callstack );
else
return (LHS)obj;
}
/*
Our children are a prefix expression and any number of suffixes.
<p>
We don't eval() any nodes until the suffixes have had an
opportunity to work through them. This lets the suffixes decide
how to interpret an ambiguous name (e.g. for the .class operation).
*/
private Object eval( boolean toLHS,
CallStack callstack, Interpreter interpreter)
throws EvalError
{
Object obj = jjtGetChild(0);
int numChildren = jjtGetNumChildren();
for(int i=1; i<numChildren; i++)
obj = ((BSHPrimarySuffix)jjtGetChild(i)).doSuffix(
obj, toLHS, callstack, interpreter);
/*
If the result is a Node eval() it to an object or LHS
(as determined by toLHS)
*/
if ( obj instanceof SimpleNode )
if ( obj instanceof BSHAmbiguousName )
if ( toLHS )
obj = ((BSHAmbiguousName)obj).toLHS(
callstack, interpreter);
else
obj = ((BSHAmbiguousName)obj).toObject(
callstack, interpreter);
else
// Some arbitrary kind of node
if ( toLHS )
// is this right?
throw new EvalError("Can't assign to prefix.",
this, callstack );
else
obj = ((SimpleNode)obj).eval(callstack, interpreter);
// return LHS or value object as determined by toLHS
if ( obj instanceof LHS )
if ( toLHS )
return obj;
else
try {
return ((LHS)obj).getValue();
} catch ( UtilEvalError e ) {
throw e.toEvalError( this, callstack );
}
else
return obj;
}
}
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