Map<String,Double> excepMap = item.getException(); StringBuffer permission = new StringBuffer(); for(int i =0;i<excepMap.size();i++){ Set<String> exceptionS = excepMap.keySet(); String[] st = new String[exceptionS.size()]; int j = 0 ; for(String exceptionL : exceptionS){ st[i++] = exceptionL; permission.append(exceptionL+"@"); } } System.out.print("看看几个异常:"+permission.toString());
最后的StringBUffer对象拼接后会多出一个“@”符号,下边代码是去掉最后的符号:
String permissionStr = permission.toString(); permissionStr = permissionStr.substring(0,permissionStr.length()-1);//去除多余符号
StringBuilder与 StringBuffer 哪个好点?