jodd-core/src/main/java/jodd/util/StringUtil.java
public static String cutBetween(final String string, final String left, final String right) {
		int leftNdx = string.indexOf(left);
		if (leftNdx == -1) {
			return null;
		}

		int rightNdx = string.indexOf(right);
		if (rightNdx == -1) {
			return null;
		}

		leftNdx += left.length();

		if (leftNdx >= rightNdx) {
			return StringPool.EMPTY;
		}

		return string.substring(leftNdx, rightNdx);
	}
public static String cutBetween(final String string, final String left, final String right) {
		int leftNdx = string.indexOf(left);
		if (leftNdx == -1) {
			return null;
		}

		int rightNdx = string.indexOf(right);
		if (rightNdx == -1) {
			return null;
		}

		leftNdx += left.length();

		if (leftNdx >= rightNdx) {
			return StringPool.EMPTY;
		}

		return string.substring(leftNdx, rightNdx);
	}
Cuts a string between two other strings. If either of left and right
is missing, nothing will be cut and <code>null</code> is returned.
If indexes of left or right strings are wrong, empty string is returned.