Penukaran jenis data Java, apakah perbezaan antara parseXXX(String) atau valueOf(String)?

Question

Apakah perbezaan antara parseparseXXX(String) dan valueOf(String) jenis asas kelas pembungkusan?

Answer 1

Kod sumber JDK8

 /**
 * Returns an {@code Integer} object holding the value
 * extracted from the specified {@code String} when parsed
 * with the radix given by the second argument. The first argument
 * is interpreted as representing a signed integer in the radix
 * specified by the second argument, exactly as if the arguments
 * were given to the {@link #parseInt(java.lang.String, int)}
 * method. The result is an {@code Integer} object that
 * represents the integer value specified by the string.
 *
 * <p>In other words, this method returns an {@code Integer}
 * object equal to the value of:
 *
 * <blockquote>
 *  {@code new Integer(Integer.parseInt(s, radix))}
 * </blockquote>
 *
 * @param      s   the string to be parsed.
 * @param      radix the radix to be used in interpreting {@code s}
 * @return     an {@code Integer} object holding the value
 *             represented by the string argument in the specified
 *             radix.
 * @exception NumberFormatException if the {@code String}
 *            does not contain a parsable {@code int}.
 */
public static Integer valueOf(String s, int radix) throws NumberFormatException {
    return Integer.valueOf(parseInt(s,radix));
}

Menggunakan Inteager untuk menggambarkan di sini, valueOf sebenarnya memanggil parseInt.
Kaedah parseInt ialah kaedah statik kelas Integer Fungsinya adalah untuk menukar rentetan menjadi integer int
valueOf juga merupakan kaedah statik kelas Integer objek.