Index: trunk/modules/luni/src/main/java/java/util/AbstractCollection.java =================================================================== --- trunk/modules/luni/src/main/java/java/util/AbstractCollection.java (revision 448441) +++ trunk/modules/luni/src/main/java/java/util/AbstractCollection.java (working copy) @@ -352,16 +352,18 @@ StringBuilder buffer = new StringBuilder(size() * 16); buffer.append('['); Iterator it = iterator(); - while (it.hasNext()) { - Object next = it.next(); - if (next != this) { - buffer.append(next); - } else { - buffer.append("(this Collection)"); //$NON-NLS-1$ + if (it != null) { + while (it.hasNext()) { + Object next = it.next(); + if (next != this) { + buffer.append(next); + } else { + buffer.append("(this Collection)"); //$NON-NLS-1$ + } + if(it.hasNext()) { + buffer.append(", "); //$NON-NLS-1$ + } } - if(it.hasNext()) { - buffer.append(", "); //$NON-NLS-1$ - } } buffer.append(']'); return buffer.toString();