function Test() 
{ 
  var _data = ""; 
  this.getString = function() 
  { 
    //设置成同步 
    DWREngine.setAsync(false);  
    //调用Java类Test的getString方法，callBackFun为回调函数 
    JTest.getString(function(data){_data = data;} 
    //重新设置为异步方式 
    DWREngine.setAsync(true);  
    return _data; 
  } 
} 

function Test() 
{ 
  var _data = ""; 
  this.getString = function() 
  {    
    //调用Java类Test的getString方法，callBackFun为回调函数 
    JTest.getString( {  
callback:function(data){_data = data;},  
                   async:false  
                 }  
                );   
    return _data; 
  } 
}