```java
package com.gosuncn;
import java.io.FileOutputStream;
import java.io.IOException;
public class JavaIOOutputStream {
public static final String DESTINATION_FILENAME = "C:\\Users\\Administrator\\Desktop\\UTF8.txt";
public static void main(String[] args) throws Exception {
flush(new FileOutputStream(DESTINATION_FILENAME));
}
public static void write1(FileOutputStream outputStream) throws IOException {
/**
* 默认写入int低八位的一字节数据.
* 如果文件不存在,则默认是创建新文件.
* 如果文件存在,则默认是删除原文件,创建新文件.
*/
outputStream.write(97);
}
public static void write2(FileOutputStream outputStream) throws IOException {
byte[] data = new byte[3];
data[0] = 97;
data[1] = 98;
data[2] = 99;
outputStream.write(data); // 写入字节数组
}
public static void write3(FileOutputStream outputStream) throws IOException {
byte[] data = new byte[3];
data[0] = 97;
data[1] = 98;
data[2] = 99;
/**
* off 偏移data的off字节数
* len 写入len个字节
*/
outputStream.write(data, 1, 1);
}
public static void flush(FileOutputStream outputStream) throws IOException {
outputStream.write(97);
outputStream.flush(); // 将缓冲区的内容刷到磁盘
}
}
```
