import java.io.*
class MyFile
{
MyFile(String d)
{
this.d=d
}
void write(String path,String datafile)
{
File f=new File(this.d)
StringBuilder sb=new StringBuilder()
String savepath
String[] strs
BufferedOutputStream bos
byte[] buf
this.path=path.endsWith("\\") ? path.substring(0,path.length()-1) : path
savepath=this.path+"\\"+datafile
try
{
strs=f.list()
for(String str : strs)
{
sb.append(str)
sb.append("\r\n")
}
bos=new BufferedOutputStream(new FileOutputStream(savepath),MyFile.Size)
buf=sb.toString().getBytes()
bos.write(buf,0,buf.length)
//bos.flush()
bos.close()
}
catch(Exception e)
{
System.out.println(e.getMessage())
}
}
void show(String datafile)
{
String fp=datafile.contains("\\") ? datafile : this.path+"\\"+datafile
File f=new File(fp)
BufferedInputStream bis
byte[] buf
try
{
buf=new byte[(int)f.length()]
bis=new BufferedInputStream(new FileInputStream(f),MyFile.Size)
bis.read(buf,0,buf.length)
System.out.println(new String(buf))
bis.close()
}
catch(Exception e)
{
System.out.println(e.getMessage())
}
}
private static final int Size=8*1024
private String d,path
}
public class P
{
public static void main(String[] args)
{
Scanner sc=new Scanner(System.in)
MyFile f
String d,path,datafile
System.out.print("请输入windows系统中某个目录的路径：")
d=sc.nextLine()
f=new MyFile(d)
System.out.print("请输入保存数据的文件的路径：")
path=sc.nextLine()
System.out.print("请输入保存数据的文件的文件名：")
datafile=sc.nextLine()
f.write(path,datafile)
f.show(datafile)
sc.close()
}
}
分为读字节，读字符两种读法\x0d\x0a◎◎◎FileInputStream 字节输入流读文件◎◎◎\x0d\x0apublic class Maintest {\x0d\x0a\x0d\x0apublic static void main(String[] args) throws IOException {\x0d\x0a\x0d\x0aFile f=new File("G:\\just for fun\\xiangwei.txt")\x0d\x0a\x0d\x0aFileInputStream fin=new FileInputStream(f)\x0d\x0a\x0d\x0abyte[] bs=new byte[1024]\x0d\x0a\x0d\x0aint count=0\x0d\x0awhile((count=fin.read(bs))>0)\x0d\x0a{\x0d\x0a\x0d\x0aString str=new String(bs,0,count)//反复定义新变量：每一次都 重新定义新变量，接收新读取的数据\x0d\x0a\x0d\x0aSystem.out.println(str)//反复输出新变量：每一次都 输出重新定义的新变量\x0d\x0a}\x0d\x0afin.close()\x0d\x0a}\x0d\x0a}\x0d\x0a\x0d\x0a◎◎◎FileReader 字符输入流读文件◎◎◎\x0d\x0apublic class Maintest {\x0d\x0apublic static void main(String[] args) throws IOException {\x0d\x0a\x0d\x0aFile f=new File("H:\\just for fun\\xiangwei.txt")\x0d\x0a\x0d\x0aFileReader fre=new FileReader(f)\x0d\x0a\x0d\x0aBufferedReader bre=new BufferedReader(fre)\x0d\x0a\x0d\x0aString str=""\x0d\x0awhile((str=bre.readLine())!=null)//●判断最后一行不存在，为空\x0d\x0a{\x0d\x0aSystem.out.println(str)\x0d\x0a}\x0d\x0abre.close()\x0d\x0a fre.close()\x0d\x0a\x0d\x0a}\x0d\x0a\x0d\x0a}
