/*****************************************************************************
* *
* 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;
/**
This class handles both while(){} statements and do{}while() statements.
*/
class BSHWhileStatement extends SimpleNode implements ParserConstants
{
public boolean isDoStatement;
BSHWhileStatement(int id) { super(id); }
public Object eval( CallStack callstack, Interpreter interpreter)
throws EvalError
{
int numChild = jjtGetNumChildren();
// Order of body and condition is swapped for do / while
SimpleNode condExp, body = null;
if ( isDoStatement ) {
condExp = (SimpleNode)jjtGetChild(1);
body =(SimpleNode)jjtGetChild(0);
} else {
condExp = (SimpleNode)jjtGetChild(0);
if ( numChild > 1 ) // has body, else just for side effects
body =(SimpleNode)jjtGetChild(1);
}
boolean doOnceFlag = isDoStatement;
while(
doOnceFlag ||
BSHIfStatement.evaluateCondition(condExp, callstack, interpreter )
)
{
if ( body == null ) // no body?
continue;
Object ret = body.eval(callstack, interpreter);
boolean breakout = false;
if(ret instanceof ReturnControl)
{
switch(((ReturnControl)ret).kind )
{
case RETURN:
return ret;
case CONTINUE:
continue;
case BREAK:
breakout = true;
break;
}
}
if(breakout)
break;
doOnceFlag = false;
}
return Primitive.VOID;
}
}
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