public static String removeStart(String str, String remove) {
        if (isEmpty(str) || isEmpty(remove)) {
            return str;
        }
        if (str.startsWith(remove)){
            return str.substring(remove.length());
        }
        return str;
    }
<p>Removes a substring only if it is at the beginning of a source string,
otherwise returns the source string.</p>

<p>A {@code null} source string will return {@code null}.
An empty ("") source string will return the empty string.
A {@code null} search string will return the source string.</p>

<pre>
StringUtils.removeStart(null, *)      = null
StringUtils.removeStart("", *)        = ""
StringUtils.removeStart(*, null)      = *
StringUtils.removeStart("www.domain.com", "www.")   = "domain.com"
StringUtils.removeStart("domain.com", "www.")       = "domain.com"
StringUtils.removeStart("www.domain.com", "domain") = "www.domain.com"
StringUtils.removeStart("abc", "")    = "abc"
</pre>

@param str  the source String to search, may be null
@param remove  the String to search for and remove, may be null
@return the substring with the string removed if found,
 {@code null} if null String input
@since 2.1
android/android_framework/base/src/main/java/lang3/StringUtils.java