Java 流

package mio;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;

public class FileStreamTest2 {

	public static void main(String[] args) throws IOException {
		File fp = new File("a.txt");
		/*
		 * Java中有字节流和字符流两大类，下面的字节流可以通过不同的编码方式封装成为字符流
		 * FileOutputStream 是字节流，因为OutputStream是字节类，同理带有InputStream
		 * OutputStreamWriter 是字符流，因为Writer是字符类，同理带有Reader的是字符流
		 * fop 是FileOutputStream实例，
		 * writer 是writer实例
		 * 所以writer在实例化的过程中，需要两个参量，一个是字节流对象，一个是编码方式，才是字符流对象
		 */
		FileOutputStream fop = new FileOutputStream(fp);
		OutputStreamWriter writer = new OutputStreamWriter(fop, "UTF-8");
		writer.append("中文");
		writer.append("\r\n");
		writer.append("english");
		writer.close();
		fop.close();
		
		FileInputStream fip = new FileInputStream(fp);
		InputStreamReader reader = new InputStreamReader(fip, "UTF-8");
		StringBuffer sb = new StringBuffer();
		while(reader.ready()) {
			sb.append((char)reader.read());
		}
		System.out.println(sb.toString());
		reader.close();
		fip.close();
	}

}