Thinking in java 琐碎知识点之 I/O流 、对象序列化(七)

例程：InputTest.java
public class InputTest {
	public static void main(String[] args) throws IOException {
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
//		int len=br.read();
//		System.out.println((char)len);
//		String len2=br.readLine();
//		System.out.println(len2);
		
//		Scanner sn=new Scanner(System.in);
//		System.out.println(sn.nextLine());
//		System.out.println(sn.nextInt());
		String input = "1 fish 3 fish red fish blue fish";
	     Scanner s = new Scanner(input).useDelimiter("\\s*fish\\s*");//自定义分隔符为fish
	     System.out.println(s.nextInt());
	     System.out.println(s.nextInt());
	     System.out.println(s.next());
	     System.out.println(s.next());
	     
	     input="324 42314 fish zpc";
	     s=new Scanner(input);
	     System.out.println(s.nextInt());
	     System.out.println(s.nextInt());
	     System.out.println(s.next());
	    // System.out.println(s.nextByte(0));
	     s.close(); 
	}
}
//Scanner也可以指定读取某个文件
public class TestScanner {
	public  static void main(String[] args){
		Scanner sn=null;
		//sn.useDelimiter("\n");//如果增加这一行将只把回车符作为分隔符
		try {
			sn=new Scanner(new File("F:\\Thinking.txt"));
			while(sn.hasNext()){
				System.out.println(sn.nextLine());
			}
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}

package Serialize;
/*
 * 功能:读一个文件,复制自身追加到此文件,操作完成后文件应该变成双倍大小
 * RandomAccessFile对象不能向文件的指定位置插入内容,这会覆盖原来的内容
 * 如果要在指定位置插入内容,程序需要先把插入点后面的内容都入缓冲区,
 * 等把需要插入的数据写入文件后,在将缓冲区的内容追加到文件后面,详见InsertContent.java
 */
import java.io.*;


public class RandomAccessFileTest {
	public static void main(String[] args) {
		RandomAccessFile raf = null;
		// 以只读方式打开一个RandomAccessFile对象
		try {
			raf = new RandomAccessFile("F:\\掀起你的盖头来.mp3", "rw");
			System.out.println("RandomAccessFile对象的文件指针初始位置："
					+ raf.getFilePointer());
			System.out.println("raf.length():"+raf.length());
			//读文件
			byte[] b = new byte[1024];
			int hasRead = 0;
			int readTotal=0;
			long FileTotalLen= raf.length();
			while (((hasRead = raf.read(b)) != -1)&&readTotal<=FileTotalLen) {
				readTotal+=hasRead;
				//System.out.println(new String(b, 0, hasRead));
				raf.seek(raf.length());
				raf.write(b);
				raf.seek(readTotal);
			}
			
			System.out.println("raf.length():"+raf.length());
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			try {
				if (raf != null) {
					raf.close();
				}
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
	}
}


//InsertContent.java
import java.io.*;
/*
 * 功能：向一个文件的指定位置插入内容,而不覆盖原有的内容
 */
public class InsertContent {
	public static void main(String[] args) {
		insert("F:\\thinking.txt",200,"===========我是鸟鹏！==========");
	}
	public static void insert(String fileName, long pos, String content) {
		InputStream is = null;
		OutputStream os = null;
		RandomAccessFile raf = null;
		// 创建一个临时文件来保存插入点后面的数据
		try {
			File temp = File.createTempFile("tem", null);
			temp.deleteOnExit();
			raf = new RandomAccessFile(fileName, "rw");
			os=new FileOutputStream(temp);
			byte[] buf=new byte[1024];
			int hasRead=0;
			raf.seek(pos);
			while((hasRead=raf.read(buf))!=-1){
				os.write(buf,0,hasRead);
			}
			raf.seek(pos);
			raf.write(content.getBytes());
			
			//下面的代码实现插入数据的功能
			is=new FileInputStream(temp);
			while((hasRead=is.read(buf))!=-1){
				raf.write(buf,0,hasRead);
			}
		} catch (IOException e) {
			e.printStackTrace();
		}finally{
			try {
				if(raf!=null)
				raf.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}
}

例程：
import java.io.Serializable;
public class Person implements Serializable {
	private String name ;
	private int age;
	p