Test136 Wrapper 클래스 (1)

 

/*========================================
  ■■■ 자바의 주요(중요) 클래스 ■■■
  - Wrapper 클래스
==========================================*/

public class Test136
{
	public static void main(String[] args)
	{
		boolean bi = true;
		Boolean wrapbi = new Boolean(bi);
		Boolean wBi = bi;		//-- 오토 박싱

		int n = 300;
		Integer wrapn = new Integer(n);
		int n2 = wrapn;			//--오토 언박싱

		float f = 300.3f;
		Float wrapf = new Float(f);

		System.out.println(wrapbi.toString());
		System.out.println(wrapn.toString());
		System.out.println(wrapf.toString());
		//--==>>true
		//	300
		//	300.3


		System.out.println(wrapbi);
		System.out.println(wrapn);
		System.out.println(wrapf);
		//--==>>true
		//	300
		//	300.3

		String sn = "12";
		int ni = Integer.parseInt(sn);
		System.out.printf("ni : %3d\n", ni);
		//--==>> ni : 12

		ni = Integer.parseInt("0101", 2);
		System.out.printf("ni : %3d\n", ni);
		//--==>> ni :   5

		ni = Integer.parseInt("12", 8);
		System.out.printf("ni : %3d\n", ni);
		//--==>> ni : 10

		ni = Integer.parseInt("A",16);
		System.out.printf("ni : %3d\n", ni);
		//--==>> ni :  10

		sn = Integer.toBinaryString(20);
		System.out.printf("sn : %s\n", sn);
		//--==>> sn : 10100

		sn = Integer.toHexString(31);
		System.out.printf("sn : %s\n", sn);
		//--==>> sn : 1f
		
		sn = Integer.toOctalString(31);
		System.out.printf("sn : %s\n", sn);
		//--==>> sn : 37

		Integer num = new Integer(50);
		System.out.println(num.toString());
		//--==>> 50
		
		int n3 = 345;
		Integer n4 = Integer.valueOf(n3);
		System.out.println(n4);
		//--==>> 345

	}
}