问：说说Java中有哪些IO流吧？

Java 中的 IO 流（输入/输出流），主要包括以下几种基本类型：

1. 字节输入/输出流：

   • 输入流：InputStream 及其子类
   • 输出流：OutputStream 及其子类

2. 字符输入/输出流：

   • 输入流：Reader 及其子类
   • 输出流：Writer 及其子类

3. 装饰者流：用于增强功能，如缓冲、处理等。

   • 缓冲流：BufferedInputStream, BufferedOutputStream, BufferedReader, BufferedWriter
   • 处理流：DataInputStream, DataOutputStream, FileReader, FileWriter 等

4. 转换流：

   • InputStreamReader：将字节输入流转换为字符输入流
   • OutputStreamWriter：将字符输出流转换为字节输出流

5. 文件相关流：

   • FileInputStream 和 FileOutputStream
   • FileReader 和 FileWriter

6. 其他流：

   • ByteArrayInputStream 和 ByteArrayOutputStream
   • PipedInputStream 和 PipedOutputStream
   • SequenceInputStream
   • PrintStream 和 PrintWriter
   • RandomAccessFile

示例

1. 字节流示例：文件复制

使用 FileInputStream 和 FileOutputStream 复制文件：

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;public class FileCopy {public static void main(String[] args) {FileInputStream fis = null;FileOutputStream fos = null;try {fis = new FileInputStream("source.txt");fos = new FileOutputStream("destination.txt");byte[] buffer = new byte[1024];int bytesRead;while ((bytesRead = fis.read(buffer)) != -1) {fos.write(buffer, 0, bytesRead);}} catch (IOException e) {e.printStackTrace();} finally {try {if (fis != null) fis.close();if (fos != null) fos.close();} catch (IOException e) {e.printStackTrace();}}}
}

2. 字符流示例：文件内容读取和写入

使用 FileReader 和 FileWriter：

import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;public class FileReadWrite {public static void main(String[] args) {FileReader fr = null;FileWriter fw = null;try {fr = new FileReader("source.txt");fw = new FileWriter("destination.txt");char[] buffer = new char[1024];int charsRead;while ((charsRead = fr.read(buffer)) != -1) {fw.write(buffer, 0, charsRead);}} catch (IOException e) {e.printStackTrace();} finally {try {if (fr != null) fr.close();if (fw != null) fw.close();} catch (IOException e) {e.printStackTrace();}}}
}

3. 缓冲流示例：高效文件复制

使用 BufferedInputStream 和 BufferedOutputStream：

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;public class BufferedFileCopy {public static void main(String[] args) {BufferedInputStream bis = null;BufferedOutputStream bos = null;try {bis = new BufferedInputStream(new FileInputStream("source.txt"));bos = new BufferedOutputStream(new FileOutputStream("destination.txt"));byte[] buffer = new byte[1024];int bytesRead;while ((bytesRead = bis.read(buffer)) != -1) {bos.write(buffer, 0, bytesRead);}} catch (IOException e) {e.printStackTrace();} finally {try {if (bis != null) bis.close();if (bos != null) bos.close();} catch (IOException e) {e.printStackTrace();}}}
}

4. 转换流示例：字节流转换为字符流

使用 InputStreamReader 和 OutputStreamWriter：

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.IOException;public class ConvertStreamExample {public static void main(String[] args) {FileInputStream fis = null;FileOutputStream fos = null;InputStreamReader isr = null;OutputStreamWriter osw = null;try {fis = new FileInputStream("source.txt");fos = new FileOutputStream("destination.txt");isr = new InputStreamReader(fis, "UTF-8");osw = new OutputStreamWriter(fos, "UTF-8");char[] buffer = new char[1024];int charsRead;while ((charsRead = isr.read(buffer)) != -1) {osw.write(buffer, 0, charsRead);}} catch (IOException e) {e.printStackTrace();} finally {try {if (isr != null) isr.close();if (osw != null) osw.close();if (fis != null) fis.close();if (fos != null) fos.close();} catch (IOException e) {e.printStackTrace();}}}
}

基于 Java IO 流的不同用法，帮助大家在实际应用中选择和使用合适的IO流。