과제 4각형 절차
package org.javaro.lecture;
public class P2_1 {
public static void main(String[] args) {
System.out.println("조병수-20191016-객체");
System.out.println("\n[절차 프로그램]");
double x, y, area;
x=10;
y=20;
area = x*y;
System.out.println("4각형 면적 = "+area);
}
}
실행창

과제 4각형 함수
package org.javaro.lecture;
public class P2_2 {
public static void main(String[] args) {
System.out.println("조병수-20191016-객체");
System.out.println("\n[함수 프로그램]");
double x, y, area;
x=10;
y=20;
area = fn_area(1,x,y);
System.out.println("4각형 면적 = "+area);
}
static double fn_area(int a, double b, double c) {
double result = 0;
if(a==1) {
result = b*c;
}else if(a ==2 ) {
result = 0.5*b*c;
}
return result;
}
}
실행창

과제 4각형 객체
package org.javaro.lecture;
public class P2_3 {
public static void main(String[] args) {
System.out.println("조병수-20191016-객체");
System.out.println("\n[객체 프로그램]");
double x, y, area;
x=10;
y=20;
P2_1_1 pr1 = new P2_1_1();
pr1.b = x;
pr1.c = y;
pr1.a = 1;
System.out.println("4각형 면적 = "+pr1.fn_area());
}
}
class P2_1_1{
int a ;
double b, c;
public double fn_area() {
double result = 0;
if(a==1) {
result = b*c;
}else if(a ==2 ) {
result = 0.5*b*c;
}
return result;
}
}
실행창

과제 4각형 자바빈
package org.javaro.lecture;
public class P2_4 {
public static void main(String[] args) {
System.out.println("조병수-20191016-객체");
System.out.println("\n[자바빈 프로그램]");
double x, y, area;
x=10;
y=20;
P2_1_2 pr2 = new P2_1_2();
pr2.setB(x); pr2.setC(y);
pr2.setA(1);
System.out.println("4각형 면적 = "+pr2.fn_area());
}
}
class P2_1_2{
int a ;
double b, c;
void setA(int x) {
a = x;
}
void setB(double y) {
b = y;
}
void setC(double z) {
c = z;
}
public double fn_area() {
double result = 0;
if(a==1) {
result = b*c;
}else if(a ==2 ) {
result = 0.5*b*c;
}
return result;
}
}
실행창
