IO中flush()函数的使用代码示例

the java.io.writer.flush() method flushes the stream. if the stream has saved any characters from the various write() methods in a buffer, write them immediately to their intended destination. then, if that destination is another character or byte stream, flush it. thus one flush() invocation will flush all the buffers in a chain of writers and outputstreams.

public class demo {
	public static void main(string[] ars) throws exception {
		system.out.println("hello");
		printwriter writer = new printwriter(system.out);
		writer.println("writer start");
		//   writer.flush();
		try {
			thread.sleep(3000);
		}
		catch (interruptedexception e) {
			// todo auto-generated catch block
			e.printstacktrace();
		}
		writer.println("writer close");
		writer.close();
	}
}

如上面代码，如果flush()被注释掉，则打印完“hello”之后3秒才会打印”writer start”，”writer close”，因为writer.close()在关闭输出流前会调用一次flush()。效果如下：

如果flush()没有被注释掉，则则打印完“hello”之后会立即打印”writer start”。

总结

以上就是本文关于io中flush()函数的使用代码示例的全部内容，希望对大家有所帮助。感兴趣的朋友可以继续参阅本站其他相关专题，如有不足之处，欢迎留言指出。感谢朋友们对本站的支持！