java - Java 中的 PHP base_convert

Question

有没有一种好的方法可以在 Java 中以与 PHP 的 base_convert 函数兼容的方式进行基数转换？我一直在研究 boolean 数组，但这似乎是这个问题的一个非常复杂的解决方案。

Answer 1

经过一番摆弄和 @BoristheSpider 的建议后，这个答案似乎工作正常，包括与 PHP 中相同的与 32 位整数相关的溢出问题。

/**
 * Converts a string from one base to another base. The bases must be between
 * 2 and 36 inclusive. This function exhibits the same issues as the original
 * PHP version related to overflow in 32 bit integers.
 * 
 * @param inputValue A string representation of a number.
 * @param fromBase The starting radix of a number between 2 and 36 inclusive.
 * @param toBase The ending radix of the number between 2 and 36 inclusive.
 * @return The <code>inputValue</code> converted into <code>toBase</code> base.
 * @see http://www.php.net/manual/en/function.base-convert.php
 */
public static String base_convert(final String inputValue, final int fromBase, final int toBase) {
    if (fromBase < 2 || fromBase > 36 || toBase < 2 || toBase > 36) {
        return null;
    }
    String ret = null;
    try {
        ret = Integer.toString(Integer.parseInt(inputValue, fromBase), toBase);
    } catch(Exception ex) {};
    return ret;
}

为了奖励积分，可以轻松包装此函数以提供 PHP 的 bindec 和 decbin 功能:

/**
 * Converts a decimal string into a binary string.
 * 
 * @param inputValue A string representation of a decimal number.
 * @return A bit string representation of the <code>inputValue</code>.
 */
public static String decbin(final String inputValue) {
    return Util.base_convert(inputValue, 10, 2);
}
/**
 * Converts a binary string into a decimal string.
 * 
 * @param inputValue A string representation of a binary number.
 * @return A decimal number string representation of the <code>inputValue</code>.
 */
public static String bindec(final String inputValue) {
    return Util.base_convert(inputValue, 2, 10);
}