java - 如何检查和匹配 arraylist 元素的可能组合

Question

String [] A = {"High","Medium","Low"};
String [] B = {"High","Medium","Low"};
String [] C = {"High","Medium","Low"};
String [] D = {"High","Medium","Low"};
String [] E = {"High","Medium","Low"};
String [] F = {"High","Medium","Low"};

JComboBox Ai = new JComboBox(A); JComboBox Bi = new JComboBox(B);
JComboBox Ci = new JComboBox(C); JComboBox Di = new JComboBox(C);
JComboBox Ei = new JComboBox(E); JComboBox Fi = new JComboBox(F);

....

//add the user choice in arrayList
ArrayList<String> a = new ArrayList<String>();
a.add((String) Ai.getSelectedItem());
a.add((String) Bi.getSelectedItem());
a.add((String) Ci.getSelectedItem());
a.add((String) Di.getSelectedItem());
a.add((String) Ei.getSelectedItem());
a.add((String) Fi.getSelectedItem());

已编辑:
设想:有 6 组(Ai、Bi、Ci、Di、Ei、Fi)可供选择。在每组上，有3个子选项(高(H)，中(M)，低(L))。用户需要在6个组中的每一个上选择一个

选择可以是例如"HHHLLL"或 "MMMLLM"或 "HHLLMM"等

在不编写很多 else if 的情况下检查和匹配用户选择的最佳方法是什么？例如

if(Ai=="High" && Bi=="High" && Ci=="Low" && Di=="High" && Ei=="Low" && Fi=="Medium") {
    System.out.println("Good Choice"); 
}

谢谢。

Answer 1

首先，您不需要为每个 JComboBox 提供新的选择列表。

String[] choices = {"High", "Medium", "Low"};

JComboBox ai = new JComboBox(choices);
JComboBox bi = new JComboBox(choices);
JComboBox ci = new JComboBox(choices);
JComboBox di = new JComboBox(choices);
JComboBox ei = new JComboBox(choices);
JComboBox fi = new JComboBox(choices);

(Java中的变量通常以小写字母开头，所以我将变量名改为小写。)

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接下来，您可以将所有六个 JComboBox 放在一个数组中。您马上就会明白为什么这很有用。

JComboBox[] boxes = {ai, bi, ci, di, ei, fi};

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现在，您可以像这样制作您的用户选择字符串:

// Create an ArrayList of Strings, where each string is either "H", "M", or "L"
ArrayList<String> userChoice = new ArrayList<String>()

for (JComboBox box : boxes) {
    // Go through this code once for each JComboBox in boxes
    // The first time through, "box" means the first JComboBox
    // The second time through, "box" is the second JComboBox, etc.
    if (box.getValue().equals("High")) {
         userChoice.add("H");
    } else if (box.getValue().equals("Medium")) {
         userChoice.add("M");
    } else if (box.getValue().equals("Low")) {
         userChoice.add("L")
    }
}

您可能不熟悉 for-each 循环。它的意思是“对某物数组中的每个某物执行一次此代码。”

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如果您使用此代码，您最终会得到一个名为 userChoice 的 ArrayList，它具有类似于 ["H", "H", "M", "M", "L", "L"] 的内容。