int rd = System.in.read();
char c = (char)rd;

char[] buffer = new char[n];
try {
    System.in.read(buffer);
} catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}

import java.io.BufferedReader;
import java.io.InputStreamReader;

char[] buffer = new char[n];
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
br.read(buffer);
        
br.readLine();

import java.util.Scanner;

Scanner scan = new Scanner(System.in);
if(scan.hasNextLine()) {
    String str = scan.nextLine();
}
Scanner sc = new Scanner(System.in);
if (sc.hasNext()) {
    String str = sc.next();
}
if (sc.hasNextInt()) {
    int value = sc.nextInt();
}

StringBuilder sb = new StringBuilder();
sb.append("this array is: ");
sb.append('[');
sb.append(1);
sb.append(',');
sb.append(3.14);
sb.append(']');
System.out.println(sb.toString());