在Java中将StreamWriter转换为OutputStream？

import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Writer;
import java.nio.charset.StandardCharsets;

public class StreamWriterToOutputStream {
    public static void main(String[] args) {
        // 创建一个OutputStream
        OutputStream outputStream = new ByteArrayOutputStream();

        // 创建一个OutputStreamWriter，将字符流转换为字节流
        Writer writer = new OutputStreamWriter(outputStream, StandardCharsets.UTF_8);

        // 在这里，您可以使用writer进行写入操作

        // 关闭writer
        try {
            writer.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}