Java 문자열 역순 출력을 실현하는 네 가지 방법

/*
	 * string     
	 *   String  toCharArray()，          
	 * 2018-5-18 13:05:00
	 */
	private static void reverseString1(String str) {

		char[] chr = str.toCharArray();
		
		for (int i = chr.length-1 ; i >= 0; i--) {
			System.out.print(chr[i]);
		}
		System.out.println("\t");

	}
	

	/*
	 * string     
	 *   String    subString()  ，              。
	 * 2018-5-18 13:16:00
	 */
	private static void reverseString2(String str) {

		if (str.length() == 1)
			System.out.println(str);
		else {
			String subString1 = str.substring(0, str.length() - 1);
			String subString2 = str.substring(str.length() - 1);

			System.out.print(subString2);

			reverseString2(subString1);
		}

	}
	
	/*
	 * string     
	 *      StringBuffer ， StringBuffer   reverse()         。
	 * 2018-5-18 13:22:10
	 */
	private static void reverseString3(String str) {

		StringBuffer buffer = new StringBuffer(str);
		System.out.println(buffer.reverse());

	}

	/*
	 *      
	 *      subString()  ，       
	 *  2018-5-18 13:18:30
	 */
	private static void reverseStringMy(String str) {

		StringBuffer a = new StringBuffer();
		String subString2 = "";
		for (int i = str.length(); i > 0; i--) {
			subString2 = str.substring(i - 1, i);
			a.append(subString2);
		}
		System.out.print("My:" + a);

		System.out.println("\t");
	}

public static void main(String[] args) {

	        String str1 = "abc";
		System.out.println(str1.substring(2));

		String str = "holle world";
		//     4   
		reverseString1(str);
		reverseString2(str);
		reverseString3(str);
		reverseStringMy(str);

	}

c
dlrow elloh	
dlrow elloh
dlrow elloh
My:dlrow elloh