/*****************************************************************************
* Licensed to the Apache Software Foundation (ASF) under one *
* or more contributor license agreements. See the NOTICE file *
* distributed with this work for additional information *
* regarding copyright ownership. The ASF licenses this file *
* to you under the Apache License, Version 2.0 (the *
* "License"); you may not use this file except in compliance *
* with the License. You may obtain a copy of the License at *
* *
* http://www.apache.org/licenses/LICENSE-2.0 *
* *
* Unless required by applicable law or agreed to in writing, *
* software distributed under the License is distributed on an *
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY *
* KIND, either express or implied. See the License for the *
* specific language governing permissions and limitations *
* under the License. *
* *
* *
* This file is part of the BeanShell Java Scripting distribution. *
* Documentation and updates may be found at http://www.beanshell.org/ *
* Patrick Niemeyer (pat@pat.net) *
* Author of Learning Java, O'Reilly & Associates *
* *
*****************************************************************************/
package bsh;
/**
* This class handles both {@code while} statements and {@code do..while} statements.
*/
class
BSHWhileStatement extends
SimpleNode implements
ParserConstants {
/**
* Set by Parser, default {@code false}
*/
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
final
SimpleNode condExp;
final
SimpleNode body;
if (
isDoStatement) {
condExp = (
SimpleNode)
jjtGetChild(1);
body = (
SimpleNode)
jjtGetChild(0);
} else {
condExp = (
SimpleNode)
jjtGetChild(0);
if (
numChild > 1) {
body = (
SimpleNode)
jjtGetChild(1);
} else {
body = null;
}
}
boolean
doOnceFlag =
isDoStatement;
while (
doOnceFlag ||
BSHIfStatement.
evaluateCondition(
condExp,
callstack,
interpreter)) {
doOnceFlag = false;
// no body?
if (
body == null) {
continue;
}
Object ret =
body.
eval(
callstack,
interpreter);
if (
ret instanceof
ReturnControl) {
switch (((
ReturnControl)
ret).
kind) {
case
RETURN:
return
ret;
case
CONTINUE:
break;
case
BREAK:
return
Primitive.
VOID;
}
}
}
return
Primitive.
VOID;
}
}