java急需关注的知识点-标准I0流

java需要关注的知识点---标准I0流
System.in

public class SystemInTest {public static void main(String[] args) throws IOException {BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in));String s;while((s = stdin.readLine())!= null && s.length()!= 0) {System.out.println(s);}}}

public class SystemOutTest {public static void main(String[] args) {PrintWriter out = new PrintWriter(System.out,true);out.println("Hello,World");}}

public class Redirecting {public static void main(String[] args) throws IOException, InterruptedException {PrintStream console = System.out;BufferedInputStream in = new BufferedInputStream(new FileInputStream("D:\\RSA75WP\\test\\src\\com\\io\\Redirecting.java"));PrintStream out = new PrintStream(new BufferedOutputStream(new FileOutputStream("test.out")));System.setIn(in);System.setOut(out);System.setErr(out);BufferedReader br = new BufferedReader(new InputStreamReader(System.in));Thread.sleep(4000);String s;while((s = br.readLine())!= null) {System.out.println(s);}out.close();System.setOut(console);}}