import java.util.HashMap;
import java.util.Map;public class Test {/*** 方法1：使用集合类 (Map以外的集合类也可以随意使用)* 目标：返回一个数组的最大值和最小值*/public Map<String, Integer> test1(int[] arr) {Map<String, Integer> map = new HashMap<String, Integer>();int max = Integer.MIN_VALUE;int min = Integer.MAX_VALUE;for (int i = 0; i < arr.length; i++) {if (arr[i] > max) {max = arr[i];}if (arr[i] < min) {min = arr[i];}}map.put("max", max);map.put("min", min);return map;}/*** 方法2：使用封装对象* 目标：返回一个数组的最大值和最小值*/public Result test2(int[] arr) {Result result = new Result();int max = Integer.MIN_VALUE;int min = Integer.MAX_VALUE;for (int i = 0; i < arr.length; i++) {if (arr[i] > max) {max = arr[i];}if (arr[i] < min) {min = arr[i];}}result.setMax(max);result.setMin(min);return result;}/*** 方法3：使用引用传递 (不适用基本类型及其封装类和String类型)* 目标：返回数组长度，同时获取最大值和最小值*/public int test3(int[] arr, Result result) {int max = Integer.MIN_VALUE;int min = Integer.MAX_VALUE;for (int i = 0; i < arr.length; i++) {if (arr[i] > max) {max = arr[i];}if (arr[i] < min) {min = arr[i];}}result.setMax(max);result.setMin(min);int total = arr.length;return total;}/*** 测试main*/public static void main(String[] args) {Test t = new Test();int[] arr = { 1, 2, 3, 4, 5, 6 };// ----------方法1测试-----------// Map<String, Integer> map = t.test1(arr);// System.out.println("max : " + map.get("max"));// System.out.println("min : " + map.get("min"));// ----------方法2测试-----------// Result result = t.test2(arr);// System.out.println("max : " + result.getMax());// System.out.println("min : " + result.getMin());// ----------方法3测试-----------Result result = new Result();int total = t.test3(arr, result);System.out.println("total : " + total);System.out.println("max : " + result.getMax());System.out.println("min : " + result.getMin());}}class Result {int max;int min;// 构造函数public Result() {super();}// getters/setters(略)
}