JAVA自学之-----FileInputStream类

package coreJava;

import java.io.FileInputStream;
import java.io.IOException;

public class IOUtil {

    public static void printHex(String Filename)throws IOException{
        /**
         * 读取指定文件内荣，按照16进制输出到控制台，并且
         * 没输出10byte换行
         */
        FileInputStream in = new FileInputStream(Filename);
        int b;
        int i = 1;
        while((b = in.read())!=-1){
            if(b <= 0xf){
                //单位数前面补零
                System.out.print("0");
            }
            //以十六进制的形式输出显示，并且以空格分隔
            System.out.print(Integer.toHexString(b)+"  ");
            //当每行输出大于等于十个字节时换行
            if(i++%10 == 0){
                System.out.println();
            }
        }
        //关闭文件，避免异常错误
        in.close();
    }
}

package coreJava;

import java.io.IOException;

public class IOUtilTest1 {

    public static void main(String[] args)throws IOException {
        // TODO Auto-generated method stub
        IOUtil.printHex("E:\\JAVA IO\\testJava\\联通1.txt");
    }

}