java程序设计基础_陈国君版第五版_第十章例题

java程序设计基础_陈国君版第五版_第十章例题

import java.io.*;
public class Main10_1 {
	public static void main(String [] args)
	{
		FileInputStream fin;
		FileOutputStream fout;
		char ch;
		int data;
		try
		{
			fin = new FileInputStream(FileDescriptor.in);
			fout = new FileOutputStream("d:\\miyao.txt");
			System.out.println("请输入一串字符，并以‘#’结束");
			while((ch = (char)fin.read())!='#')
				fout.write(ch);
			fin.close();
			fout.close();
			System.out.println();
			fin = new FileInputStream("d:\\miyao.txt");
			fout = new FileOutputStream(FileDescriptor.out);
			while(fin.available()>0)
			{
				data = fin.read();
				fout.write(data);
			}
			fin.close();
			fout.close();
		}
		catch(FileNotFoundException e)
		{
			System.out.println("文件没找到！");
		}
		catch(IOException e)
		{}
	}
}

import java.io.*;
public class Main10_2 {
	public static void main(String[] args)throws IOException
	{
		FileInputStream fi = new FileInputStream("d:\\大爷.gif");
		FileOutputStream fo = new FileOutputStream("d:\\大爷1.gif");
		System.out.println("文件的大小 ="+fi.available());
		byte[] b = new byte[fi.available()];
		fi.read(b);
		fo.write(b);
		System.out.println("文件已经被复制！");
		fi.close();
		fo.close();
	}
}

import java.io.*;
public class Main10_3 {
	public static void main(String[] args){
		FileOutputStream fout;
		DataOutputStream dout;
		FileInputStream fin;
		DataInputStream din;
		try
		{
			fout = new FileOutputStream("d:\\temp");
			dout = new DataOutputStream(fout);
			dout.writeInt(10);
			dout.writeLong(12345);
			dout.writeFloat(3.1415926f);
			dout.writeDouble(987654321.123);
			dout.writeBoolean(true);
			dout.writeChars("Goodbye!");
		}
		catch(IOException e){}
		try 
		{
			fin = new FileInputStream("d:\\temp");
			din = new DataInputStream(fin);
			System.out.println(din.readInt());
			System.out.println(din.readLong());
			System.out.println(din.readFloat());
			System.out.println(din.readDouble());
			System.out.println(din.readBoolean());
			char ch;
			while((ch=din.readChar())!='\0')
				System.out.print(ch);
			din.close();
		}
		catch(FileNotFoundException e)
		{
			System.out.println("文件未找到！");
		}
		catch(IOException e)
		{}
	}
}

import java.io.*;
public class Main10_4 {
	public static void main(String[] args){
		try 
		{
			byte[] b = new byte[128];
			System.out.print("请输入字符：");
			int count = System.in.read(b);System.out.println("输入的是：");
			for(int i = 0 ; i< count-2;i++)
			{
				System.out.print((char)b[i]+" ");
			}
			System.out.println();
			System.out.println("输入的字符个数为"+count);
			Class InClass = System.in.getClass();
			Class OutClass = System.out.getClass();
			System.out.println("in所在的类是："+InClass.toString());
			System.out.println("out锁在的类是："+OutClass.toString());
		}
		catch(IOException e)
		{}
	}
}

import java.io.*;
public class Main10_5 {
	public static void main(String[] args)throws IOException
	{
		char[] c = new char[500];
		FileReader fr = new FileReader("d:\\miyao.txt");
		int num = fr.read(c);
		String str = new String(c,0,num);
		System.out.println("读取的字符个数为："+num+",其内容如下：");
		System.out.println(str);
		fr.close();
	}
}

import java.io.*;
public class Main10_6 {
	public static void main(String[] args)throws IOException{
		FileWriter fw = new FileWriter("d:\\miyao.txt");
		char[] c = {'H','e','l','l','o','\r','\n'};
		String str = "欢迎使用Java！";
		fw.write(c);
		fw.write(str);
		fw.close();
	}
}

import java.io.*;
public class Main10_7 {
	public static void main(String[] args)throws IOException
	{
		String thisLine;
		int count = 0;
		try
		{
			FileReader fr = new FileReader("d:\\miyao.txt");
			BufferedReader bfr = new BufferedReader(fr);
			while((thisLine = bfr.readLine())!=null)
			{
				count++;
				System.out.println(thisLine);
			}
			System.out.println("共读取了"+count+"行");
			bfr.close();
		}
		catch(IOException ioe)
		{
			System.out.println("错误！"+ioe);
		}
	}
}

import java.io.*;
public class Main10_8 {
	public static void main(String[] args){
		String str = new String();
		try
		{
			BufferedReader in = new BufferedReader(new FileReader("d:\\miyao.txt"));
			BufferedWriter out = new BufferedWriter(new FileWriter("d:\\miyao1.txt"));
			while((str = in.readLine())!=null)
			{
				System.out.println(str);
				out.write(str);
				out.newLine();
			}
			out.flush();
			in.close();
			out.close();
		}
		catch(IOException ioe)
		{
			System.out.println("错误！"+ioe);
		}
	}
}

import java.io.*;
public class Main10_9 {
	public static void main(String[] args)throws IOException{
		String str = new String();
		try
		{
			InputStreamReader isr = new InputStreamReader(System.in);
			BufferedReader inp = new BufferedReader(isr);
			String sdir = " d:\\cgj";
			String sfile;
			File fdir1 =new File(sdir);
			if(fdir1.exists()&&fdir1.isDirectory())
			{
				System.out.println("文件夹:"+sdir+"已经存在");
				for(int i =0; i<fdir1.list().length;i++)
					System.out.println((fdir1.list())[i]);
				File fdir2 = new File("d:\\cgj\\temp");
				if(!fdir2.exists())
					fdir2.mkdir();
				System.out.println();
				System.out.println("建立新文件夹后的文件列表");
				for(int i =0;i<fdir1.list().length;i++)
					System.out.println((fdir1.list())[i]);
			}
			System.out.print("请输入该文件夹中的一个文件名：");
			sfile = inp.readLine();
			File ffile = new File(fdir1,sfile);
			if(ffile.isFile())
			{
				System.out.print("文件名："+ffile.getName());
				System.out.print(";所在文件夹："+ffile.getPath());
				System.out.println(";文件大小:"+ffile.length()+"字节");
			}
			if(inp!=null) inp.close();
		}
		catch(IOException e)
		{
			System.out.println(e.toString());
		}
	}
}

import java.io.*;
public class Main10_10 {
	public static void main(String[] args)throws IOException
	{
		StringBuffer stfDir = new StringBuffer();
		System.out.println("请输入文件锁在的路径");
		char ch;
		while((ch = (char)System.in.read())!='\r')
			stfDir.append(ch);
		File dir = new File(stfDir.toString());
		System.out.println("请输入欲读取的文件名");
		StringBuffer stfFileName = new StringBuffer();
		char c;
		while((c = (char)System.in.read())!='\r')
			stfFileName.append(c);
		stfFileName.replace(0,1,"");
		File readFrom = new File(dir,stfFileName.toString());
		if(readFrom.isFile() && readFrom.canWrite() && readFrom.canRead())
		{
			RandomAccessFile rafFile = new RandomAccessFile(readFrom,"rw");
			while(rafFile.getFilePointer()<rafFile.length())
				System.out.println(rafFile.readLine());
			rafFile.close();
		}
		else
			System.out.println("文件不可读！");
	}
}