java读取properties文件

public class CityNoUtil {
private static Properties message = new Properties();

static{
InputStream is = Thread.currentThread().getContextClassLoader().getResourceAsStream("cityno.properties");
try {
message.load(is);
} catch (IOException e) {
e.printStackTrace();
}
}

public String getMessageByKey(String key){
return message.getProperty(key,AjaxResponse.ERROR);
}
}