Java-----Scanner Class __java

Package day12_01;
*
 * * Guide package; Create object; Invoke Method
 * There is a static field under the System class:
 * Public     static final inputstream in; standard input stream, corresponding to keyboard input
 *    
 * InputStream is=system.in
 *    
 class demo{
 * public      static final int x=10;
 * Public      static final Student s=new Student ();
 * *      } *  int y=demo.x;
 *  Student S=demo.s;
 * * *  Construction Method:
 *  Scanner (inputstream source)
 /
Import java.util.scanner;//Guide Bag Public
class Scannerdemo {public
       static void Main (string[] args) {
        //Create object
       Scanner sc=new Scanner ( system.in);
       int X=sc.nextint ();
       System.out.println ("x:" +x);
       }

Member Methods

Package day12_02;
Import Java.util.Scanner;
*
 * Basic format:
 * public boolean hasnextxxx ():
 * public Xxx nextxxx ():
 *
 * Example: int
 * Public Boolean has Nextint ()
 * public int nextint ()
 *
 Note
 * inputmismatchexception: input and what you want does not match
* * Public Class Scannerdemo {public
       static void Main (string[] args) {
             //Create object
             Scanner sc = new Scanner (system.in); 
  //Get Data
             if (Sc.hasnextint ()) {
                int x=sc.nextint ();
                System.out.println ("x:" +x);

             }
             else {
                    System.out.println ("The data you entered is incorrect");}}

Two commonly used methods

Package day12_03;
Import Java.util.Scanner; * * Common two methods * public int nextint () * Public String nextline () * * Problem: Get a value first, then get a string * main reason: newline symbol \ n * Solve the problem: * A To get a numeric value, then create a new keyboard input object to get the string * B. All the data is followed by the string, then what, the corresponding conversion of what * * public class Scannerdemo {public static void M
                    Ain (string[] args) {Scanner sc=new Scanner (system.in);
Gets the value//int a=sc.nextint () of two int types;
int B=sc.nextint ();
System.out.println ("A:" +a+ ", B:" +b);

                    System.out.println ("-------------");
Gets the value//String S1=sc.nextline () of two string classes;
String S2=sc.nextline ();
System.out.println ("S1:" +s1+ ", S2:" +s2);

                    System.out.println ("-------------");
Gets a string S1=sc.nextline () in the fetch of an int value//string;
int B=sc.nextint (); System.out.println("S1:" +s1+ ", B:" +b);

                    System.out.println ("------------");
First get an int value, in get a string//int a =sc.nextint ();
String S2=sc.nextline ();

                    System.out.println ("A:" +a+ ", S2:" +s2);

                    int A=sc.nextint ();
                    Scanner sc2=new Scanner (system.in);
                    String S=sc2.nextline ();
             System.out.println ("A:" +a+ ", S:" +s);
 }
}