在Java（intellij）中进行元素周期表搜索

Question

目标是制作元素周期表搜索引擎。询问用户问题以缩小结果范围，或者用户是否知道刚输入的元素的名称。一旦输入或找到了元素，它将提供有关该元素的信息。我只有几个细节和几个元素来使代码正常工作，还会添加更多元素和细节，例如结构和原子量。

无论何时找到结果，它都不会提供信息，而只会显示空白屏幕。我以为将它放在toString这个类中，然后在我的主体底部调用它就足够了，但是我无法弄清丢失的内容。似乎是一个简单的系统输出打印命令，但这也不起作用。

非常感谢您的帮助。

import java.util.ArrayList;
import javax.swing.*;

public class Main {

public static void main(String args[]) {

    ArrayList<Element> e = new ArrayList<Element>();
    String choice, element = "", searchBy, symbol, chemGroupBlock, list = "", str = "";

    e.add(new Element("Hydrogen", "Nonmetal", "H", 1));
    e.add(new Element("Helium", "Nobel Gas", "He", 2));
    e.add(new Element("Lithium", "Alkali Metal", "Li", 3));

    choice = JOptionPane.showInputDialog(null,
            "Do you know the name of the element you're looking for?"
                    + "(Yes/No)", "Welcome to the Chem Table!", 3);

    if (choice.equalsIgnoreCase("yes")) {
        element = JOptionPane.showInputDialog(null,
                "Enter the name of the Element.. ",
                "Welcome to the Chem Table!", JOptionPane.PLAIN_MESSAGE);
    }else if (choice.equalsIgnoreCase("no")) {
        searchBy = JOptionPane.showInputDialog(null,
                "Search by: 'chemical group block' or 'symbol'?", "Welcome to the Chem Table", 3);

        if (searchBy.equalsIgnoreCase("chemGroupBlock")) {
            chemGroupBlock = JOptionPane.showInputDialog(null,
                    "Enter Chemical Group Block (Nonmetal/Nobel Gases/Alkalies)",
                    "Welcome to The Chem Table", JOptionPane.PLAIN_MESSAGE);
            for (int i = 0; i < e.size(); i++){
                if (e.get(i).getchemGroupBlock().equals(chemGroupBlock)){
                    list = list + e.get(i).getName() + "\n";
                }
            }

            element = JOptionPane.showInputDialog(null, list,
                    JOptionPane.PLAIN_MESSAGE);

        } else if (searchBy.equalsIgnoreCase("symbol")) {
            symbol = JOptionPane.showInputDialog(null,
                    "Enter the element symbol:(He/NaCl/Xe)",
                    "Welcome to the Chem Table",
                    JOptionPane.PLAIN_MESSAGE);
            for (int i = 0; i < e.size(); i++) {
                if (e.get(i).getSymbol().equals(symbol)) {
                    list = list + e.get(i).getName() + "\n";
                }
            }
            element = JOptionPane.showInputDialog(null, list,
                    JOptionPane.PLAIN_MESSAGE);

        }
    }
    for (int i = 0; i < e.size(); i++) {
        if (e.get(i).getName().equals(element)) {
            str = e.get(i).toString();
        }
    }

    JOptionPane.showMessageDialog(null, str, "Element Results", 1);


 }
}

这里是元素的类

public class Element {
private String name;
private String chemGroupBlock;
private String symbol;
private int atomicNumber;



public Element(String name, String chemGroupBlock, String symbol, int atomicNumber) {

    this.name = name;
    this.chemGroupBlock = chemGroupBlock;
    this.symbol = symbol;
    this.atomicNumber = atomicNumber;
}

public String getName(){
    return name;
}

public String getchemGroupBlock(){
    return chemGroupBlock;
}

public String getSymbol(){

    return symbol;
}

public int getatomicNumber(){
    return atomicNumber;
}

public String toString() {
    return "Element: " + name + "\nChemical Group Block: " + chemGroupBlock + "\nSymbol: " + symbol + "\nAtomic Number" + atomicNumber;
   }
}

Answer 1

if (e.get(i).getName().equals(element))

您是否输入了元素的区分大小写的确切名称？例如，找不到“氢”，但“氢”可以正常工作。

您应将此条件更改为：

if(e.get(i).getName().equalsIgnoreCase(element))

代码的其他部分也有其他类似的问题。我建议您对自己的逻辑进行全面审查。致电equals时应格外注意，是否应设为equalsIgnoreCase

Answer 2

关于按符号或化学组进行搜索，有一个多余的输入对话框，在输入字段中打印-1（它是JOptionPane.PLAIN_MESSAGE的值：]

element = JOptionPane.showInputDialog(null, list, JOptionPane.PLAIN_MESSAGE);

最好使用“选项对话框”，用户只需单击一个按钮即可选择一个选项，而不用键入它。

接下来，当您按符号搜索时，将提供数据中不可用的选项（例如NaCl和Xe）。
因此，要解决这些问题，您可能需要按如下所示更新代码：
if (result == JOptionPane.YES_OPTION) {
    element = JOptionPane.showInputDialog(
        null, "Enter the name of the Element.. ",
        "Welcome to the Chem Table!", JOptionPane.PLAIN_MESSAGE);
} else if (result == JOptionPane.NO_OPTION) {
    String[] byOptions = {"chemical group block",  "symbol"};
    result = JOptionPane.showOptionDialog(
                null, 
                "Search by: 'chemical group block' or 'symbol'?",
                "Welcome to the Chem Table", 
                JOptionPane.DEFAULT_OPTION, JOptionPane.QUESTION_MESSAGE,
                null, byOptions, byOptions[0]);

    if (result == 0) {
        String[] byGroup = {"Nonmetal", "Nobel Gases", "Alkalies"};
        result = JOptionPane.showOptionDialog(
                    null,
                    "Select Chemical Group", 
                    "Welcome to The Chem Table",
                    JOptionPane.DEFAULT_OPTION, JOptionPane.QUESTION_MESSAGE,
                    null, byGroup, byGroup[0]);
        for (Element el : e) {
            if (el.getchemGroupBlock().equalsIgnoreCase(byGroup[result])) {
                element = el.getName();
                break;
            }
        }
    } else { // search by symbol
        symbol = JOptionPane.showInputDialog(
                    null, "Enter the element symbol:(H/He/Li)",
                    "Welcome to the Chem Table",
                    JOptionPane.PLAIN_MESSAGE);
        for (Element el : e) {
            if (el.getSymbol().equalsIgnoreCase(symbol)) {
                element = el.getName();
                break;
            }
        }
        if (element.isEmpty()) {
            JOptionPane.showMessageDialog(
                null, "Symbol" + symbol + " not found!", "Not found!", JOptionPane.WARNING_MESSAGE);
            return;
        }
    }
}