Java IO中的缓冲流如何使用

在Java IO中，缓冲流（Buffered Streams）可以用于提高读写性能。缓冲流分为两种：BufferedInputStream（用于读取字节数据）和BufferedOutputStream（用于写入字节数据）。以下是如何使用这两种缓冲流的示例：

1. 使用BufferedInputStream读取文件：

import java.io.FileInputStream;
import java.io.BufferedInputStream;
import java.io.IOException;

public class BufferedInputStreamExample {
    public static void main(String[] args) {
        try {
            FileInputStream fileInputStream = new FileInputStream("input.txt");
            BufferedInputStream bufferedInputStream = new BufferedInputStream(fileInputStream);

            int data;
            while ((data = bufferedInputStream.read()) != -1) {
                System.out.print((char) data);
            }

            bufferedInputStream.close();
            fileInputStream.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

2. 使用BufferedOutputStream写入文件：

import java.io.FileOutputStream;
import java.io.BufferedOutputStream;
import java.io.IOException;

public class BufferedOutputStreamExample {
    public static void main(String[] args) {
        try {
            FileOutputStream fileOutputStream = new FileOutputStream("output.txt");
            BufferedOutputStream bufferedOutputStream = new BufferedOutputStream(fileOutputStream);

            String text = "Hello, this is a sample text!";
            byte[] data = text.getBytes();

            bufferedOutputStream.write(data);
            bufferedOutputStream.flush(); // 刷新缓冲区，将数据写入文件

            bufferedOutputStream.close();
            fileOutputStream.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

注意：在使用缓冲流时，建议使用try-with-resources语句，这样可以自动关闭流并释放资源。以下是使用try-with-resources的示例：

import java.io.FileInputStream;
import java.io.BufferedInputStream;
import java.io.IOException;

public class BufferedInputStreamExample {
    public static void main(String[] args) {
        try (FileInputStream fileInputStream = new FileInputStream("input.txt");
             BufferedInputStream bufferedInputStream = new BufferedInputStream(fileInputStream)) {

            int data;
            while ((data = bufferedInputStream.read()) != -1) {
                System.out.print((char) data);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}