Wrapper 클래스 실습

public classWrapperEx {

 

             /**

              * @paramargs

              */

             public static voidmain(String[] args) {

                           // TODOAuto-generated method stub

 

                           Integeri1 = newInteger(20);

                           Integeri2 = newInteger("40");

                          

//                        디폴트 생성자가 없음

//                        Integeri3 = new Integer();

 

                           int i= i2.intValue();

                           float f= i2.floatValue();

                          

                           // 문자열"100"를 정수로 형변환하기

                           Stringstr = "100";

                           int i3= Integer.parseInt(str);

                          

                           // 문자열"10.0"을 실수로 형변환하기

                           Stringstr2 = "10.0";

                           float f3= Float.parseFloat(str2);

                          

                           // 정수 100을 문자열로 형변환하기

                           int i4=100;

                           Stringstr3 = i4 +"";

                           Stringstr4 = String.valueOf(i4);

                          

                           // 진법 변환

                          

                          

                           //157쪽

                          

                           System.out.println("byte의 최소값 :" + Byte.MIN_VALUE);

                           System.out.println("byte의 최대값" +Byte.MAX_VALUE);

                           System.out.println("short의 최소값" +Short.MIN_VALUE);

                           System.out.println("short의 최대값" +Short.MAX_VALUE);

                           System.out.println("int의 최소값" +Integer.MIN_VALUE);

                          System.out.println("int의 최대값" +Integer.MAX_VALUE);

                           System.out.println("long의 최소값" +Long.MIN_VALUE);

                           System.out.println("long의 최대값" +Long.MAX_VALUE);

                          

                           System.out.println("float의 최소값" +Float.MIN_VALUE);

                           System.out.println("의 최대값" +Float.MAX_VALUE);

                           System.out.println("double의 최소값" +Double.MIN_VALUE);

                           System.out.println("double의 최대값" +Double.MAX_VALUE);

             }

 

} 

 

 

byte의 최소값 : -128
byte의 최대값127
short의 최소값-32768
short의 최대값32767
int의 최소값-2147483648
int의 최대값2147483647
long의 최소값-9223372036854775808
long의 최대값9223372036854775807
float의 최소값1.4E-45
의 최대값3.4028235E38
double의 최소값4.9E-324
double의 최대값1.7976931348623157E308