//1. 验证金额,包含负数,保留2位小数 public static void main(final String[] args) { String data = "55.50"; if(!data.matches( "^(((-?)[1-9]{1}\\d*)|([0]{1}))(\\.(\\d){0,2})?$")){ System.out.println("格式错误"); }else{ System.out.println("格式正确"); } }