设有一个含若干水果单词组成的字符串数组，编程统计该数组中共有多少种水果。假设调试的数据如下： ‏ ‌ String fruit[]= { "apple","pear","apple","apple","orange","pear","apple"};

可以使用哈希表来统计每种水果出现的次数，然后再统计哈希表中键值对的数量即可得到不同种类的水果数量。

以下是Java代码示例：

import java.util.HashMap;

public class FruitCounter {
    public static void main(String[] args) {
        String fruit[] = {"apple", "pear", "apple", "apple", "orange", "pear", "apple"};
        HashMap<String, Integer> fruitCount = new HashMap<String, Integer>();
        for (int i = 0; i < fruit.length; i++) {
            if (fruitCount.containsKey(fruit[i])) {
                fruitCount.put(fruit[i], fruitCount.get(fruit[i]) + 1);
            } else {
                fruitCount.put(fruit[i], 1);
            }
        }
        System.out.println("共有" + fruitCount.size() + "种水果：");
        for (String fruitName : fruitCount.keySet()) {
            System.out.println(fruitName + "出现了" + fruitCount.get(fruitName) + "次");
        }
    }
}

输出结果：

共有3种水果：
orange出现了1次
pear出现了2次
apple出现了4次