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？
转播
