第13次抽考(IO流）

1、将文本文件a.txt 复制成 b.txt。要求：
a. 用逐个字符复制方式；
b. 用逐行读写方式；
c. 用字符数组方式
2、将压缩包a.rar复制成b.rar。
注意：复制前后手工打开文件，若复制后无法打开，则说明复制文件有误。
3、设计一个单链表，配备基本的创建、输出等操作。通过序列化机制将其写入文件，再通过反序列化机制从文件中读出。在序列化前/后输出链表内容。

一.

1.a:

package week4;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

//将文本文件a.txt复制成b.txt
public class Work1 {
    public static void main(String[] args) throws IOException
    {
      File a=new File("a.txt");
      //a.createNewFile();
      File b =new File("b.txt");
      //b.createNewFile();
     //文本文件用FileReader/FileWriter
     try {
        FileReader in =new FileReader(a);//这里就像一个水管接上了a.txt,a.txt像水龙头，当我们要read的时候就会放水
        FileWriter out =new FileWriter(b);//这里一个水管接上了b.txt，b.txt像池子当我们要write的时候就会将水倒入池子中
        int ch;//这里是ASCILL码的值
        while((ch=in.read())!=-1)
        {
            out.write(ch);
        }
        in.close();
        out.close();
        System.out.println("复制完成");

    } catch (FileNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }catch(IOException e)
     {
        e.printStackTrace();
     }

    }
}

1.b:

package week4;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

//采用缓冲区进行逐行读取
public class Work1 {
    public static void main(String[] args) throws IOException
    {
      //创建文件
        File a=new File("a.txt");
        File b=new File("b.txt");
        //接入水管和池子
        FileReader in =new FileReader(a);
        FileWriter out=new FileWriter(b);
        //用BufferedReader包装，成为一个缓冲区
        BufferedReader b_in=new BufferedReader(in);
        BufferedWriter b_out=new BufferedWriter(out);
        System.out.println("开始文件复制");
        String s;
        while((s=b_in.readLine())!=null)
        {
            b_out.write(s,0,s.length());
            b_out.newLine();
        }
        b_in.close();
        b_out.close();
        System.out.println("结束文件复制");

    }
}

1.c

package week4;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
//采用字符数组来作为缓冲区来复制文件
public class Work1 {
    public static void main(String[] args) throws IOException
    {
        //创建文件对象
      File a=new File("a.txt");
      File b=new File("b.txt");
      char[] ca=new char[(int)a.length()];
      FileReader in=new FileReader(a);
      FileWriter out=new FileWriter(b);
      System.out.println("开始文件复制");
      in.read(ca);
      out.write(ca);
      in.close();
      out.close();
      System.out.println("文件复制结束");
    }
}

2.复制压缩包

package week4;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
//使用字节流复制压缩包文件
public class Work1 {
    public static void main(String[] args) throws IOException
    {
        File a=new File("a.zip");
        File b=new File("b.zip");
        FileInputStream in =new FileInputStream(a);
        FileOutputStream out=new FileOutputStream(b);
        int ch;
        while((ch=in.read())!=-1)
        {
            out.write(ch);
        }
        System.out.println("复制完成");

    }
}

3.

package week4;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.Scanner;
//序列化单链表，只有实现Serializable接口，才能序列化，transient修饰的不会被序列化
public class Work1 {
    public static void main(String[] args) throws IOException
    {
        Node a=new Node(0);
        a.create();
        a.print();
        //先将对象写入输出流，恰好相反
        FileOutputStream fo=new FileOutputStream("serialObj.dat");
        ObjectOutputStream obj_o=new ObjectOutputStream(fo);
        obj_o.writeObject(obj_o);
        obj_o.close();
        //从dat文件中读取
        FileInputStream fi=new FileInputStream("serialObj.dat");
        ObjectInputStream obj_i=new ObjectInputStream(fi);
        try {
            Node b=(Node)obj_i.readObject();
            obj_i.close();
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }
}
class Node implements Serializable
{
    Node next;
    int value;
    public Node(int value)
    {
        this.value=value;
    }
    //创建单链表
    public void create()
    {
        int tmpValue;
        Scanner sc=new Scanner(System.in);
        Node p=this;
        while((tmpValue=sc.nextInt())!=-1)
        {
            Node n=new Node(tmpValue);
            p.next=n;
            p=n;
        }
        p.next=null;
        System.out.println("创建成功");

    }
    //打印单链表
    public void print()
    {
        Node p=this;
        while(p!=null)
        {
            System.out.println(p.value);
            p=p.next;
        }
    }
}