JavaNIO-Buffer缓冲区

public class NIODemo {
    public static void main(String[] args) {
        String str = "www.mldn.cn" ;//定义要保存到缓冲区的字符串
        ByteBuffer buffer = ByteBuffer.allocate(20);//分配20个容量的缓冲区
        System.out.println("1【开辟缓冲区】position="+buffer.position()+"、limit="+buffer.limit()+"、capacity="+buffer.capacity());
        buffer.put(str.getBytes());//数据保存到缓冲区之中
        System.out.println("2【写入缓冲区】position="+buffer.position()+"、limit="+buffer.limit()+"、capacity="+buffer.capacity());
        buffer.flip();//重置缓冲区，才可以进行数据读取
        System.out.println("3【重置缓冲区】position="+buffer.position()+"、limit="+buffer.limit()+"、capacity="+buffer.capacity());
        while (buffer.hasRemaining()){//判断position与limit之间是否还有数据
            System.out.print(buffer.get()+"、");//获取的是字节编码数据
        }
        System.out.println("n4【缓冲区操作完毕】position="+buffer.position()+"、limit="+buffer.limit()+"、capacity="+buffer.capacity());
        buffer.clear();//清空缓冲区
        System.out.println("5【清空缓冲区缓冲区】position="+buffer.position()+"、limit="+buffer.limit()+"、capacity="+buffer.capacity());
    }
}