A Html.fromHtml() TagHandler to support <del> on Android <= 6

DelTagHandler.java

import android.text.Editable;
import android.text.Html;
import android.text.Spannable;
import android.text.Spanned;
import android.text.style.StrikethroughSpan;

import org.xml.sax.XMLReader;

public class DelTagHandler implements Html.TagHandler {
	public void handleTag(boolean opening, String tag, Editable output, XMLReader xmlReader) {
		if (opening) {
			handleStartTag(tag, output);
		} else {
			handleEndTag(tag, output);
		}
	}

	private void handleStartTag(String tag, Editable output) {
		if (tag.equalsIgnoreCase("del")) {
			start(output, new Strikethrough());
		} else if (tag.equalsIgnoreCase("s")) {
			start(output, new Strikethrough());
		} else if (tag.equalsIgnoreCase("strike")) {
			start(output, new Strikethrough());
		}
	}

	private void handleEndTag(String tag, Editable output) {
		if (tag.equalsIgnoreCase("del")) {
			end(output, Strikethrough.class, new StrikethroughSpan());
		} else if (tag.equalsIgnoreCase("s")) {
			end(output, Strikethrough.class, new StrikethroughSpan());
		} else if (tag.equalsIgnoreCase("strike")) {
			end(output, Strikethrough.class, new StrikethroughSpan());
		}
	}

	private void start(Editable text, Object mark) {
		int len = text.length();
		text.setSpan(mark, len, len, Spannable.SPAN_INCLUSIVE_EXCLUSIVE);
	}

	private void end(Editable text, Class kind, Object repl) {
		Object obj = getLast(text, kind);
		if (obj != null) {
			setSpanFromMark(text, obj, repl);
		}
	}

	private <T> T getLast(Spanned text, Class<T> kind) {
		/*
		 * This knows that the last returned object from getSpans()
		 * will be the most recently added.
		 */
		T[] objs = text.getSpans(0, text.length(), kind);
		if (objs.length == 0) {
			return null;
		} else {
			return objs[objs.length - 1];
		}
	}

	private void setSpanFromMark(Spannable text, Object mark, Object... spans) {
		int where = text.getSpanStart(mark);
		text.removeSpan(mark);
		int len = text.length();
		if (where != len) {
			for (Object span : spans) {
				text.setSpan(span, where, len, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
			}
		}
	}

	private static class Strikethrough {
	}
}