java - 设置页面-设置组合结果

Question

我正在创建一个用于生成密码的应用程序的设置页面。在我的选项页面中，用户可以选择 5 个选项。

我想知道如何使我的代码比为每个可能的结果使用 if 更简单。我一开始有 3 个选项，这让事情变得很容易，但现在有太多的组合，代码变得困惑，我不知道如何更好地编写它。

下面的代码用于用户可以选择的三个选项:

主要 Activity Java

  btnGenPass.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            if (SettingsPage.isSpecChecked ==  1 && SettingsPage.isHighCaseChecked == 1 && SettingsPage.isNumbChecked == 1) {
                char[] chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!£$%^&*()".toCharArray();
                final StringBuilder sb = new StringBuilder();
                Random random = new Random();
                for (int i = 0; i < SettingsPage.passLength; i++) {
                    char c = chars[random.nextInt(chars.length)];
                    sb.append(c);
                }

                final String output = sb.toString();
                passView.setText(output);

            }else if (SettingsPage.isSpecChecked == 0 && SettingsPage.isHighCaseChecked == 1 && SettingsPage.isNumbChecked == 1) {
                char[] chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789".toCharArray();
                final StringBuilder sb = new StringBuilder();
                Random random = new Random();
                for (int i = 0; i < SettingsPage.passLength; i++) {
                    char c = chars[random.nextInt(chars.length)];
                    sb.append(c);
                }

                final String output = sb.toString();
                passView.setText(output);

            }else if (SettingsPage.isSpecChecked == 0 && SettingsPage.isHighCaseChecked == 0 && SettingsPage.isNumbChecked == 1) {
                char[] chars = "abcdefghijklmnopqrstuvwxyz0123456789".toCharArray();
                final StringBuilder sb = new StringBuilder();
                Random random = new Random();
                for (int i = 0; i < SettingsPage.passLength; i++) {
                    char c = chars[random.nextInt(chars.length)];
                    sb.append(c);
                }

                final String output = sb.toString();
                passView.setText(output);

            }else if (SettingsPage.isSpecChecked == 0 && SettingsPage.isHighCaseChecked == 0 && SettingsPage.isNumbChecked == 0) {
                char[] chars = "abcdefghijklmnopqrstuvwxyz".toCharArray();
                final StringBuilder sb = new StringBuilder();
                Random random = new Random();
                for (int i = 0; i < SettingsPage.passLength; i++) {
                    char c = chars[random.nextInt(chars.length)];
                    sb.append(c);
                }
                final String output = sb.toString();
                passView.setText(output);

            }else if (SettingsPage.isSpecChecked == 1 && SettingsPage.isHighCaseChecked == 0 && SettingsPage.isNumbChecked == 0) {
                char[] chars = "abcdefghijklmnopqrstuvwxyz!£$%^&*()".toCharArray();
                final StringBuilder sb = new StringBuilder();
                Random random = new Random();
                for (int i = 0; i < SettingsPage.passLength; i++) {
                    char c = chars[random.nextInt(chars.length)];
                    sb.append(c);
                }

                final String output = sb.toString();
                passView.setText(output);

            }else if (SettingsPage.isSpecChecked == 1 && SettingsPage.isHighCaseChecked == 0 && SettingsPage.isNumbChecked == 1) {
                char[] chars = "abcdefghijklmnopqrstuvwxyz1234567890!£$%^&*()".toCharArray();
                final StringBuilder sb = new StringBuilder();
                Random random = new Random();
                for (int i = 0; i < SettingsPage.passLength; i++) {
                    char c = chars[random.nextInt(chars.length)];
                    sb.append(c);
                }

                final String output = sb.toString();
                passView.setText(output);

            }else if (SettingsPage.isSpecChecked == 0 && SettingsPage.isHighCaseChecked == 1 && SettingsPage.isNumbChecked == 0) {
                char[] chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ".toCharArray();
                final StringBuilder sb = new StringBuilder();
                Random random = new Random();
                for (int i = 0; i < SettingsPage.passLength; i++) {
                    char c = chars[random.nextInt(chars.length)];
                    sb.append(c);
                }

                final String output = sb.toString();
                passView.setText(output);
            }
        }
    });

正如您所看到的，有许多语句具有所有可能的组合，但现在我添加了更多设置，有很多可能的结果组合。我相信有 32 种可能的组合。

Answer 1

你有很多重复的代码。唯一真正改变的是生成密码的字符集。您应该做的第一件事是将重复代码移至方法中。

private void generatePassword(char[] charset) {
    final StringBuilder sb = new StringBuilder();
    Random random = new Random();
    for (int i = 0; i < passLength; i++) {
        char c = charset[random.nextInt(charset.length)];
        sb.append(c);
    }

    final String output = sb.toString();
    passView.setText(output);
}

下一部分是处理字符集生成。为此，您可以创建变量来存储每个选项的字符集，例如数字、特殊字符、大写字母、小写字母等。然后根据打开/关闭的选项生成最终的字符集。

private char[] generateCharSet() {
    String numbers = "0123456789";
    String special = "!£$%^&*()";
    String alphabetsLower = "abcdefghijklmnopqrstuvwxyz";
    String alphabetsUpper = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";

    // Add lower alphabets by default
    StringBuilder finalCharset = new StringBuilder(alphabetsLower);

    // Add special chars if option is selected
    if (isSpecChecked == 1) {
        finalCharset.append(special);
    }

    // Add upper case chars if option is selected
    if (isHighCaseChecked == 1) {
        finalCharset.append(alphabetsUpper);
    }

    // Add numbers if option is selected
    if (isNumbChecked == 1) {
        finalCharset.append(numbers);
    }

    // build the final character set
    return finalCharset.toString().toCharArray();
}

在 onClick 方法中调用这些方法。希望你能明白。

这是我用一个单元模拟的整个 java 类来测试功能。它是用 Netbeans IDE 编写的。祝你好运:)

PasswordGeneratorClass.java

import java.util.Random;

/**
 *
 * @author K Neeraj Lal
 */
public class PasswordGeneratorClass {

    private static final int passLength = 40;

    private static int isSpecChecked;
    private static int isHighCaseChecked;
    private static int isNumbChecked;

    public static void main(String[] args) {

        // Iterates from 000 to 111
        for (int i = 0; i < 7; i++) {
            unitTest(i);
        }
    }

    /**
     * Used for testing only
     *
     * @param test input
     */
    private static void unitTest(int test) {
        char[] arr = Integer.toBinaryString(test).toCharArray();

        // turn on/off the options based
        isSpecChecked = Integer.parseInt(Character.toString(arr.length > 0 ? arr[0] : '0'));
        isHighCaseChecked = Integer.parseInt(Character.toString(arr.length > 1 ? arr[1] : '0'));
        isNumbChecked = Integer.parseInt(Character.toString(arr.length > 2 ? arr[2] : '0'));

        char[] charset = generateCharSet();
        generatePassword(charset);
    }

    /**
     * Generates character set
     *
     * @return character set
     */
    private static char[] generateCharSet() {
        String numbers = "0123456789";
        String special = "!£$%^&*()";
        String alphabetsLower = "abcdefghijklmnopqrstuvwxyz";
        String alphabetsUpper = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";

        // Add lower alphabets by default
        StringBuilder finalCharset = new StringBuilder(alphabetsLower);

        // Add special chars if option is selected
        if (isSpecChecked == 1) {
            finalCharset.append(special);
        }

        // Add upper case chars if option is selected
        if (isHighCaseChecked == 1) {
            finalCharset.append(alphabetsUpper);
        }

        // Add numbers if option is selected
        if (isNumbChecked == 1) {
            finalCharset.append(numbers);
        }

        // build the final character set
        return finalCharset.toString().toCharArray();
    }

    /**
     * Generates the password based on character set
     *
     * @param charset the character set to generate the password from
     */
    private static void generatePassword(char[] charset) {
        final StringBuilder sb = new StringBuilder();
        Random random = new Random();
        for (int i = 0; i < passLength; i++) {
            char c = charset[random.nextInt(charset.length)];
            sb.append(c);
        }

        final String output = sb.toString();
        // passView.setText(output);
        System.out.println(output);
    }
}