Java Utililty Methods Iterable Join

if (iterable == null)
    return null;
Iterator<E> iterator = iterable.iterator();
StringBuffer buf = new StringBuffer(256);
while (iterator.hasNext()) {
    E elem = iterator.next();
    if (elem != null)
        buf.append(elem);
...

return join(array, ",");

final StringBuilder builder = new StringBuilder();
final Iterator<String> it = items.iterator();
while (it.hasNext()) {
    builder.append(it.next());
    if (it.hasNext()) {
        builder.append(separator);
return builder.toString();

if (s == null)
    return "";
Iterator<String> iter = s.iterator();
StringBuilder builder = new StringBuilder(iter.next());
while (iter.hasNext()) {
    builder.append(delimiter).append(iter.next());
return builder.toString();
...

if (s == null)
    return "";
Iterator<String> iter = s.iterator();
StringBuilder builder = new StringBuilder(iter.next());
while (iter.hasNext()) {
    builder.append(delimiter).append(iter.next());
return builder.toString();
...

StringBuilder buffer = new StringBuilder(64);
Iterator iter = s.iterator();
if (iter.hasNext()) {
    buffer.append(nvl(iter.next(), ""));
    while (iter.hasNext()) {
        buffer.append(delimiter);
        buffer.append(nvl(iter.next(), ""));
return buffer.toString();

final StringBuilder sb = new StringBuilder();
final Iterator<String> i = source.iterator();
while (i.hasNext()) {
    String token = i.next();
    if (token != null) {
        sb.append(token);
    if (i.hasNext()) {
...

Iterator<String> iterator = null;
if (source == null) {
    return "";
iterator = source.iterator();
if (!(iterator.hasNext())) {
    return "";
StringBuilder builder = new StringBuilder(iterator.next());
while (iterator.hasNext()) {
    builder.append(separator).append(iterator.next());
return builder.toString();

return join(" ", strings);