code: public String getStack()
      {
          if (_string==null)
          {
              StringBuffer buf= new StringBuffer(512);
              
              for (int i=0;i<_stack.length;i++)
              {
                  if (i>_top)
                      buf.append(__lineSeparator);
                  buf.append(_stack[i].toString());
              }
              _string=buf.toString();
          }
          
          return _string;
      }
docs: /*-------------------------------------------------------------------