package util;import java.util.Random;/** *  * @author jkfeng * 獲得隨機字母和數字的組合（字母+數字組合，字母組合，數字組合） * */public class RandomCharOrNumUtil {public static void main(String[] args) {System.out.PRintln(getCharAndNum(6));System.out.println(getChar(6));System.out.println(getNum(6));}/** * 獲得隨機子母和數字的組合 * @param length * @return 隨機字母和數字的組合 */public static String getCharAndNum(int length) {String val = "";Random random = new Random();String charOrNum = "";for (int i = 0; i < length; i++) {if (i == 0) {charOrNum = "char";}else if (i == (length-1)) {charOrNum = "num";}else {charOrNum = (random.nextInt(2)%2 == 0) ? "char":"num";}if ("num".equalsIgnoreCase(charOrNum)) {//如何獲得 0-9之間的數字int num = random.nextInt(10);if (num == 0) {num = 2;}if (num == 1) {num = 5;}val += String.valueOf(num);}else {//如何獲得隨機的字符//97 - 122   0-25char char1  = (char)(97+random.nextInt(26));if (char1 == 'o') {char1 = 'm';}val += String.valueOf(char1);}}val = val.toUpperCase();return val; }/** * 獲得隨機字母組合 * @param length * @return 隨機字母組合 */public static String getChar(int length) {String val = "";Random random = new Random();for (int i = 0; i < length; i++) {//如何獲得隨機的字符//97 - 122   0-25char char1  = (char)(97+random.nextInt(26));val += String.valueOf(char1);}val = val.toUpperCase();return val; }/** * 獲得隨機數字組合 * @param length * @return 隨機數字組合 */public static String getNum(int length) {String val = "";Random random = new Random();for (int i = 0; i < length; i++) {//如何獲得 0-9之間的數字int num  = random.nextInt(10);val += String.valueOf(num);}val = val.toUpperCase();return val; }}