从给定的限定参考值中取名称

public class Main{
    public static void main(String[] argv){
        String qualifiedName = "java2s.com";
        System.out.println(extractName(qualifiedName));
    }
    /**
     * Extracts the name from the given qualified reference value.
     * 
     * <p>
     * For example,
     * <ul>
     * <li>"style1" is extracted from "LibA.style1"
     * <li>"style1" is returned from "style1"
     * </ul>
     * 
     * @param qualifiedName
     *            the qualified reference value
     * @return the name
     */
    public static String extractName(String qualifiedName) {
        if (qualifiedName == null)
            return null;

        int pos = qualifiedName.indexOf('.');
        if (pos == -1)
            return qualifiedName;

        return trimString(qualifiedName.substring(pos + 1));
    }
    /**
     * Trim a string. Removes leading and trailing blanks. If the resulting
     * string is empty, normalizes the string to an null string.
     * 
     * @param value
     *            the string to trim
     * @return the trimmed string, or null if the string is empty
     */

    public static String trimString(String value) {
        if (value == null)
            return null;
        value = value.trim();
        if (value.length() == 0)
            return null;
        return value;
    }
}