BufferedReader readLine()是阻塞方法
import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;public class ReadLine {public static void main(String[] args) {// System.in是标准输入（获取键盘输入的值），// InputStreamReader将字节流转为字符流，将字节流转为BufferedReaderBufferedReader br = new BufferedReader(new InputStreamReader(System.in));String line;try {// readLine()是阻塞方法，当键盘输入之后，点击回车，得到的值不会为null，就一直处于阻塞状态while ((line = br.readLine()) != null) {System.out.println(line);}} catch (IOException e) {e.printStackTrace();}}}
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