Java在两个用户数据之间找到匹配的时间顺序

Question

我为点击某个 uri 捕获了用户会话，并且需要找出匹配的按时间顺序排列的最大点击次数。例如：

User1 = {"/blue", "/green", "/pink", "/orange", "/white", "/gray"} 

User2 = {"/brown", "/green", "/pink", "/orange", "/red", "/gray"}

User3 = {"/blue", "/green", "/pink"}

User4 = {"/blue"}

我需要一个方法，它需要两个参数，并且应该返回匹配的最大点击次数，例如

场景 1-

public static void findMaxHitClick( String User1, String User2) {

    # output should be {"/green", "/pink", "/orange"}
}

场景 2-

public static void findMaxHitClick( String User3, String User4) {

    # output should be {"/blue"}
}

在java中实现上述的有效方法是什么？

Answer 1

首先，findMaxHitClick（不能声明为void）的输入和输出应该是字符串的数组或集合。

接下来，有一个方法Collections::retainAll，它允许找到两个集合的交集。

因此，findMaxHitClick 可以这样实现：

public static Collection<String> findMaxHitClick(String[] arr1, String[] arr2) {
    Set<String> s1 = new LinkedHashSet<>(Arrays.asList(arr1));
    Set<String> s2 = new LinkedHashSet<>(Arrays.asList(arr2));
    
    s1.retainAll(s2);
    
    return s1;
}

测试：

String[] User1 = {"/blue", "/green", "/pink", "/orange", "/white", "/gray"};
String[] User2 = {"/brown", "/green", "/pink", "/orange", "/red", "/gray"};
String[] User3 = {"/blue", "/green", "/pink"};
String[] User4 = {"/blue"};

System.out.println(findMaxHitClick(User1, User2));
System.out.println(findMaxHitClick(User3, User4));

输出：

[/green, /pink, /orange, /gray]  // /gray occurs in both User1 & User2
[/blue]                          // User3 & User4 have common /blue, not /red