This class is not intended for public subclassing. * *
To iterate over code points and multicharacter strings, * use a loop like this: *
* for (UnicodeSetIterator it = new UnicodeSetIterator(set); it.next();) {
* processString(it.getString());
* }
*
*
* To iterate over code point ranges, use a loop like this: *
* for (UnicodeSetIterator it = new UnicodeSetIterator(set); it.nextRange();) {
* if (it.codepoint != UnicodeSetIterator.IS_STRING) {
* processCodepointRange(it.codepoint, it.codepointEnd);
* } else {
* processString(it.getString());
* }
* }
*
*
* To iterate over only the strings, start with new UnicodeSetIterator(set).skipToStrings().
*
*
Warning: For speed, UnicodeSet iteration does not check for concurrent modification. * Do not alter the UnicodeSet while iterating. * @author M. Davis * @see UnicodeSet#ranges() * @see UnicodeSet#strings() * @see UnicodeSet#iterator() */ public class UnicodeSetIterator { // Android patch: Make UnicodeSetIterator.IS_STRING non-final. /** * Value of codepoint if the iterator points to a string. * If codepoint == IS_STRING, then examine * string for the current iteration result. */ public static int IS_STRING = -1; /** * Current code point, or the special value IS_STRING, if * the iterator points to a string. */ public int codepoint; /** * When iterating over ranges using nextRange(), * codepointEnd contains the inclusive end of the * iteration range, if codepoint != IS_STRING. If * iterating over code points using next(), or if * codepoint == IS_STRING, then the value of * codepointEnd is undefined. */ public int codepointEnd; /** * If codepoint == IS_STRING, then string points * to the current string. If codepoint != IS_STRING, the * value of string is undefined. */ public String string; /** * Create an iterator over the given set. * @param set set to iterate over */ public UnicodeSetIterator(UnicodeSet set) { reset(set); } /** * Create an iterator over nothing. next() and * nextRange() return false. This is a convenience * constructor allowing the target to be set later. */ public UnicodeSetIterator() { reset(new UnicodeSet()); } /** * Skips over the remaining code points/ranges, if any. * A following call to next() or nextRange() will yield a string, if there is one. * No-op if next() would return false, or if it would yield a string anyway. * * @return this * @see UnicodeSet#strings() */ public UnicodeSetIterator skipToStrings() { // Finish code point/range iteration. range = endRange; endElement = -1; nextElement = 0; return this; } /** * Returns the next element in the set, either a single code point * or a string. If there are no more elements in the set, return * false. If codepoint == IS_STRING, the value is a * string in the string field. Otherwise the value is a * single code point in the codepoint field. * *
The order of iteration is all code points in sorted order, * followed by all strings sorted order. codepointEnd is * undefined after calling this method. string is * undefined unless codepoint == IS_STRING. Do not mix * calls to next() and nextRange() without * calling reset() between them. The results of doing so * are undefined. *
Warning: For speed, UnicodeSet iteration does not check for concurrent modification. * Do not alter the UnicodeSet while iterating. * @return true if there was another element in the set and this * object contains the element. */ public boolean next() { if (nextElement <= endElement) { codepoint = codepointEnd = nextElement++; return true; } if (range < endRange) { loadRange(++range); codepoint = codepointEnd = nextElement++; return true; } // stringIterator == null iff there are no string elements remaining if (stringIterator == null) { return false; } codepoint = IS_STRING; // signal that value is actually a string string = stringIterator.next(); if (!stringIterator.hasNext()) { stringIterator = null; } return true; } /** * Returns the next element in the set, either a code point range * or a string. If there are no more elements in the set, return * false. If codepoint == IS_STRING, the value is a * string in the string field. Otherwise the value is a * range of one or more code points from codepoint to * codepointeEnd inclusive. * *
The order of iteration is all code points ranges in sorted
* order, followed by all strings sorted order. Ranges are
* disjoint and non-contiguous. string is undefined
* unless codepoint == IS_STRING. Do not mix calls to
* next() and nextRange() without calling
* reset() between them. The results of doing so are
* undefined.
*
* @return true if there was another element in the set and this
* object contains the element.
*/
public boolean nextRange() {
if (nextElement <= endElement) {
codepointEnd = endElement;
codepoint = nextElement;
nextElement = endElement+1;
return true;
}
if (range < endRange) {
loadRange(++range);
codepointEnd = endElement;
codepoint = nextElement;
nextElement = endElement+1;
return true;
}
// stringIterator == null iff there are no string elements remaining
if (stringIterator == null) {
return false;
}
codepoint = IS_STRING; // signal that value is actually a string
string = stringIterator.next();
if (!stringIterator.hasNext()) {
stringIterator = null;
}
return true;
}
/**
* Sets this iterator to visit the elements of the given set and
* resets it to the start of that set. The iterator is valid only
* so long as set is valid.
* @param uset the set to iterate over.
*/
public void reset(UnicodeSet uset) {
set = uset;
reset();
}
/**
* Resets this iterator to the start of the set.
*/
public void reset() {
endRange = set.getRangeCount() - 1;
range = 0;
endElement = -1;
nextElement = 0;
if (endRange >= 0) {
loadRange(range);
}
if (set.hasStrings()) {
stringIterator = set.strings.iterator();
} else {
stringIterator = null;
}
}
/**
* Gets the current string from the iterator. Only use after calling next(), not nextRange().
*/
public String getString() {
if (codepoint != IS_STRING) {
return UTF16.valueOf(codepoint);
}
return string;
}
// ======================= PRIVATES ===========================
private UnicodeSet set;
private int endRange = 0;
private int range = 0;
/**
* @hide original deprecated declaration
*/
private int endElement;
/**
* @hide original deprecated declaration
*/
private int nextElement;
/**
* Invariant: stringIterator is null when there are no (more) strings remaining
*/
private Iterator