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package a;
import java.io.*;
import java.util.Scanner;
/*4.在控制台输入一句英语, 获得每个字母出现的次数,注:每个字符作为key,出现的次数作为value*/
public class TestA {
static void f1()throws IOException //单个字写
{
FileInputStream in=new FileInputStream("D:\\11.txt");
FileOutputStream out=new FileOutputStream("D:\\12.txt");//如果该文件不存在则创建文件,如果存在会覆盖
int i;
while((i=in.read())!=-1)
{
out.write(i);
}
out.close();//从上往下开,就从下往上关
in.close();
}
static void f2()throws IOException//一次性写
{
FileInputStream in=new FileInputStream("D:\\11.txt");
FileOutputStream out=new FileOutputStream("D:\\12.txt");
byte[] b=new byte[in.available()];//一次性读到byte中
in.read(b);
out.write(b);
out.close();//从上往下开,就从下往上关
in.close();
}
static void f3()throws IOException //将文件内容输出到控制台
{
FileInputStream in=new FileInputStream("D:\\11.txt");
Scanner sc=new Scanner(in);
String str=null;
while(sc.hasNext()) {
str=sc.nextLine();
System.out.println(str);
}
sc.close();
in.close();
}
static void f4()//跳着读,一次读10个
{
FileInputStream in=new FileInputStream("D:\\11.txt");
FileOutputStream out=new FileOutputStream("D:\\12.txt");
byte[] b=new byte[in.available()];
}
public static void main(String[] args) throws IOException
{
}
}