+ /*
+ * COLLECTIONS
+ */
+ /**
+ * Convert a comma-separated separated {@link String} or a {@link String} array
+ * to a {@link List} of {@link String}, trimming them. Useful to quickly
+ * interpret OSGi services properties.
+ *
+ * @return a {@link List} containing the trimmed {@link String}s, or an empty
+ * {@link List} if the argument was <code>null</code>.
+ */
+ public static List<String> toStringList(Object value) {
+ List<String> values = new ArrayList<>();
+ if (value == null)
+ return values;
+ String[] arr;
+ if (value instanceof String) {
+ arr = ((String) value).split(",");
+ } else if (value instanceof String[]) {
+ arr = (String[]) value;
+ } else {
+ throw new IllegalArgumentException("Unsupported value type " + value.getClass());
+ }
+ for (String str : arr) {
+ values.add(str.trim());
+ }
+ return values;
+ }
+
+ /** Size of an {@link Iterable}, optimised if it is a {@link Collection}. */
+ public static int size(Iterable<?> iterable) {
+ if (iterable instanceof Collection)
+ return ((Collection<?>) iterable).size();
+
+ int size = 0;
+ for (Iterator<?> it = iterable.iterator(); it.hasNext(); size++)
+ it.next();
+ return size;
+ }
+
+ public static <T> T getAt(Iterable<T> iterable, int index) {
+ if (iterable instanceof List) {
+ List<T> lst = ((List<T>) iterable);
+ if (index >= lst.size())
+ throw new IllegalArgumentException("Index " + index + " is not available (size is " + lst.size() + ")");
+ return lst.get(index);
+ }
+ int i = 0;
+ for (Iterator<T> it = iterable.iterator(); it.hasNext(); i++) {
+ if (i == index)
+ return it.next();
+ else
+ it.next();
+ }
+ throw new IllegalArgumentException("Index " + index + " is not available (size is " + i + ")");
+ }
+
+ /*
+ * EXCEPTIONS
+ */
+ /**
+ * Chain the messages of all causes (one per line, <b>starts with a line
+ * return</b>) without all the stack
+ */
+ public static String chainCausesMessages(Throwable t) {
+ StringBuffer buf = new StringBuffer();
+ chainCauseMessage(buf, t);
+ return buf.toString();
+ }
+
+ /** Recursive chaining of messages */
+ private static void chainCauseMessage(StringBuffer buf, Throwable t) {
+ buf.append('\n').append(' ').append(t.getClass().getCanonicalName()).append(": ").append(t.getMessage());
+ if (t.getCause() != null)
+ chainCauseMessage(buf, t.getCause());
+ }
+
+ /*
+ * TIME
+ */
+ /** Formats time elapsed since start. */
+ public static String since(ZonedDateTime start) {
+ ZonedDateTime now = ZonedDateTime.now();
+ return duration(start, now);
+ }
+
+ /** Formats a duration. */
+ public static String duration(Temporal start, Temporal end) {
+ long count = ChronoUnit.DAYS.between(start, end);
+ if (count != 0)
+ return count > 1 ? count + " days" : count + " day";
+ count = ChronoUnit.HOURS.between(start, end);
+ if (count != 0)
+ return count > 1 ? count + " hours" : count + " hours";
+ count = ChronoUnit.MINUTES.between(start, end);
+ if (count != 0)
+ return count > 1 ? count + " minutes" : count + " minute";
+ count = ChronoUnit.SECONDS.between(start, end);
+ return count > 1 ? count + " seconds" : count + " second";
+ }
+