Java Utililty Methods Collection to String

final StringBuilder sb = new StringBuilder();
for (final String string : list) {
    sb.append(string).append(delimiter);
sb.setLength(sb.length() - delimiter.length());
return sb.toString();

if (c == null) {
    return "null";
} else if (c.isEmpty()) {
    return "";
StringBuilder sb = new StringBuilder();
for (T t : c) {
    sb.append(t.toString());
...

if (collection == null) {
    return "";
StringBuilder builder = new StringBuilder();
for (String item : collection) {
    if (builder.length() > 0) {
        builder.append(separator);
    builder.append(item);
return builder.toString();

int size = vals.size(), cnt = 0;
String[] strings = new String[size];
for (Iterator itr = vals.iterator(); itr.hasNext();) {
    String s = (String) itr.next();
    if (s != null) {
        strings[cnt] = s;
        cnt++;
return strings;

List<String> result = new ArrayList<String>(c.size());
for (Object e : c) {
    result.add(e.toString());
return result;

List<String> strings = new ArrayList<>();
for (T t : objects) {
    if (t == null) {
        strings.add(null);
    } else {
        strings.add(t.toString());
return strings;

switch (stringCollection.size()) {
case 0:
    return NO_STRINGS;
case 1:
    return new String[] { stringCollection.iterator().next() };
default:
    return stringCollection.toArray(new String[stringCollection.size()]);

StringBuffer buffer = new StringBuffer();
int index = 0;
for (Object obj : objects) {
    if (index++ > 0)
        buffer.append(delim);
    buffer.append(obj);
return buffer.toString();
...

if (collection.isEmpty())
    return "";
StringBuilder b = new StringBuilder();
Iterator<?> it = collection.iterator();
while (true) {
    b.append(it.next());
    if (it.hasNext()) {
        b.append(separator);
...