import java.util.Scanner;
class JavaTest {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("1번째 수 >> ");
int n1 = sc.nextInt();
System.out.println("2번째 수 >> ");
int n2 = sc.nextInt();
System.out.println(n1 / n2);
}
}
import java.util.Scanner;
class JavaTest {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
try {
System.out.println("1번째 수 >> ");
int n1 = sc.nextInt();
System.out.println("2번째 수 >> ");
int n2 = sc.nextInt();
System.out.println(n1 / n2);
}
catch (Exception e) {
e.printStackTrace();
}
}
}
import java.util.Scanner;
class JavaTest {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
try {
System.out.println("1번째 수 >> ");
int n1 = sc.nextInt();
System.out.println("2번째 수 >> ");
int n2 = sc.nextInt();
System.out.println(n1 / n2);
}
catch (Exception e) {
System.out.println(e.getMessage());
}
}
}
import java.util.Scanner;
class JavaTest {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
try {
System.out.println("1번째 수 >> ");
int n1 = sc.nextInt();
System.out.println("2번째 수 >> ");
int n2 = sc.nextInt();
System.out.println(n1 / n2);
}
catch (Exception e) {
e.printStackTrace();
}finally {
System.out.println("Finally...");
}
}
}
[Console]
1번째 수 >>
10
2번째 수 >>
0
java.lang.ArithmeticException: / by zero
Finally...
at JavaTest.main(JavaTest.java:14)
import java.util.InputMismatchException;
class JavaPractice {
public static void main(String[] args) {
try {
int num = 6 / 0;
} catch (InputMismatchException e) {
e.printStackTrace();
}
}
}
[Console]
Exception in thread "main" java.lang.ArithmeticException: / by zero
at JavaPractice.main(JavaPractice.java:7)
import java.util.InputMismatchException;
/* 표현법 1 */
catch (ArithmeticException e) {
e.printStackTrace();
}
catch (InputMismatchException e) {
e.printStackTrace();
}
/* 표현법 2 */
catch (ArithmeticException | InputMismatchException e) {
e.printStackTrace();
}
public static void main(String[] args) {
int[] arr = { 0, 1, 2 };
for (int i = 0; i <= 3; i++) {
System.out.println(arr[i]);
}
}
[Console]
0
1
2
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: Index 3 out of bounds for length 3
at JavaTest.main(JavaTest.java:9)
class A {}
class B extends A{}
class JavaTest {
public static void main(String[] args) {
A a1 = new B();
B a2 = (B)a1; // 정상적으로 casting 된다
System.out.println("Test");
A aa = new A();
B bb = (B)aa; // Exception 발생
}
}
[Console]
Test
Exception in thread "main" java.lang.ClassCastException: class A cannot be cast to class B (A and B are in unnamed module of loader 'app')
at JavaTest.main(JavaTest.java:15)
public static void main(String[] args) {
String str = null;
System.out.println(str);
int len = str.length();
}
[Console]
null
Exception in thread "main" java.lang.NullPointerException
at JavaTest.main(JavaTest.java:9)
public class ExceptionMessage {
public static void md1(int n) {
md2(n,0);
}
public static void md2(int n1, int n2) {
int r = n1 / n2;
}
public static void main(String[] args) {
// TODO Auto-generated method stub
md1(3);
System.out.println("Test...");
}
}
class Circle extends Object{
private int radius;
Circle(int radius){
this.radius = radius;
}
public double getArea(){
return Math.PI * radius * radius;
}
@Override
public String toString() {
return ("넓이는 " + getArea() + "입니다.");
}
}
class JavaTest {
public static void main(String[] args) {
Object obj = new Circle(10);
System.out.println(obj);
}
}
[Console]
넓이는 314.1592653589793입니다.