# 22.4.20 [HackerRank]Java Int to String

서태욱·2022년 4월 20일
0

## Algorithm

목록 보기
9/45

### 🌱 배경지식

#### int -> String 변환

1) Integer.toString()
Integer 클래스의 toString() method를 사용한다.

public class IntToString {
public static void main(String[] args) {
int a = 123;

String string = Integer.toString(a);

System.out.println(string);
}
}

2) String.valueOf()
java.lang.String 클래스의 valueOf() method를 사용한다.

public class IntToString {
public static void main(String[] args) {
int a = 123;

String string = String.valueOf(a);

System.out.println(string);
}
}

3) "" + n
java에서 문자열 오른쪽에 + operator를 붙이면(연산을 가하면) 새로운 문자열이 return 되는 속성을 이용한다.

The + operator, when used on the right side of a String, simply connects stuff to the right of the original String. If what it's connecting is not yet a String, it automatically converts it into one, which is what we want for this exercise.

public class IntToString {
public static void main(String[] args) {
int a = 123;

String string = "" + a;

System.out.println(string);
}
}

### ✏️ 해설 및 분석

import java.util.*;
import java.security.*;
public class Solution {
public static void main(String[] args) {

DoNotTerminate.forbidExit();

try {
Scanner in = new Scanner(System.in);
int n = in .nextInt();
in.close();
//String s=???; Complete this line below

String s = Integer.toString(n);

if (n == Integer.parseInt(s)) {
System.out.println("Good job");
} else {
}
} catch (DoNotTerminate.ExitTrappedException e) {
System.out.println("Unsuccessful Termination!!");
}
}
}

//The following class will prevent you from terminating the code using exit(0)!
class DoNotTerminate {

public static class ExitTrappedException extends SecurityException {

private static final long serialVersionUID = 1;
}

public static void forbidExit() {
final SecurityManager securityManager = new SecurityManager() {
@Override
public void checkPermission(Permission permission) {
if (permission.getName().contains("exitVM")) {
throw new ExitTrappedException();
}
}
};
System.setSecurityManager(securityManager);
}
}

re:START