//##header 1189099962000 FOUNDATION
/*
*******************************************************************************
* Copyright (C) 1996-2006, International Business Machines Corporation and *
* others. All Rights Reserved. *
*******************************************************************************
*/
package com.ibm.icu.impl;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.SortedSet;
//#ifndef FOUNDATION
//##import java.util.regex.Matcher;
//#endif
import com.ibm.icu.text.Transliterator;
import com.ibm.icu.text.UTF16;
import com.ibm.icu.text.UnicodeSet;
import com.ibm.icu.text.UnicodeSetIterator;
/**
* Utilities that ought to be on collections, but aren't
*/
public final class CollectionUtilities {
public static String join(Object[] array, String separator) {
StringBuffer result = new StringBuffer();
for (int i = 0; i < array.length; ++i) {
if (i != 0) result.append(separator);
result.append(array[i]);
}
return result.toString();
}
public static String join(Collection collection, String separator) {
StringBuffer result = new StringBuffer();
boolean first = true;
for (Iterator it = collection.iterator(); it.hasNext();) {
if (first) first = false;
else result.append(separator);
result.append(it.next());
}
return result.toString();
}
/**
* Utility like Arrays.asList()
*/
public static Map asMap(Object[][] source, Map target, boolean reverse) {
int from = 0, to = 1;
if (reverse) {
from = 1; to = 0;
}
for (int i = 0; i < source.length; ++i) {
target.put(source[i][from], source[i][to]);
}
return target;
}
public static Collection addAll(Iterator source, Collection target) {
while (source.hasNext()) {
target.add(source.next());
}
return target; // for chaining
}
public static int size(Iterator source) {
int result = 0;
while (source.hasNext()) {
source.next();
++result;
}
return result;
}
public static Map asMap(Object[][] source) {
return asMap(source, new HashMap(), false);
}
/**
* Utility that ought to be on Map
*/
public static Map removeAll(Map m, Collection itemsToRemove) {
for (Iterator it = itemsToRemove.iterator(); it.hasNext();) {
Object item = it.next();
m.remove(item);
}
return m;
}
public Object getFirst(Collection c) {
Iterator it = c.iterator();
if (!it.hasNext()) return null;
return it.next();
}
public static Object getBest(Collection c, Comparator comp, int direction) {
Iterator it = c.iterator();
if (!it.hasNext()) return null;
Object bestSoFar = it.next();
if (direction < 0) {
while (it.hasNext()) {
Object item = it.next();
int compValue = comp.compare(item, bestSoFar);
if (comp.compare(item, bestSoFar) < 0) {
bestSoFar = item;
}
}
} else {
while (it.hasNext()) {
Object item = it.next();
int compValue = comp.compare(item, bestSoFar);
if (comp.compare(item, bestSoFar) > 0) {
bestSoFar = item;
}
}
}
return bestSoFar;
}
public interface ObjectMatcher {
/**
* Must handle null, never throw exception
*/
boolean matches(Object o);
}
public static class InverseMatcher implements ObjectMatcher {
ObjectMatcher other;
public ObjectMatcher set(ObjectMatcher toInverse) {
other = toInverse;
return this;
}
public boolean matches(Object value) {
return !other.matches(value);
}
}
public static Collection removeAll(Collection c, ObjectMatcher f) {
for (Iterator it = c.iterator(); it.hasNext();) {
Object item = it.next();
if (f.matches(item)) it.remove();
}
return c;
}
public static Collection retainAll(Collection c, ObjectMatcher f) {
for (Iterator it = c.iterator(); it.hasNext();) {
Object item = it.next();
if (!f.matches(item)) it.remove();
}
return c;
}
public static boolean containsSome(Collection a, Collection b) {
// fast paths
if (a.size() == 0 || b.size() == 0) return false;
if (a == b) return true; // must test after size test.
if (a instanceof SortedSet && b instanceof SortedSet) {
SortedSet aa = (SortedSet) a;
SortedSet bb = (SortedSet) b;
aa.containsAll(null);
Comparator bbc = bb.comparator();
Comparator aac = aa.comparator();
if (bbc == null) {
if (aac == null) {
Iterator ai = aa.iterator();
Iterator bi = bb.iterator();
Comparable ao = (Comparable) ai.next(); // these are ok, since the sizes are != 0
Comparable bo = (Comparable) bi.next();
while (true) {
int rel = ao.compareTo(bo);
if (rel < 0) {
if (!ai.hasNext()) return false;
ao = (Comparable) ai.next();
} else if (rel > 0) {
if (!bi.hasNext()) return false;
bo = (Comparable) bi.next();
} else {
return true;
}
}
}
} else if (bbc.equals(a)) {
Iterator ai = aa.iterator();
Iterator bi = bb.iterator();
Object ao = ai.next(); // these are ok, since the sizes are != 0
Object bo = bi.next();
while (true) {
int rel = aac.compare(ao, bo);
if (rel < 0) {
if (!ai.hasNext()) return false;
ao = ai.next();
} else if (rel > 0) {
if (!bi.hasNext()) return false;
bo = bi.next();
} else {
return true;
}
}
}
}
for (Iterator it = a.iterator(); it.hasNext();) {
if (b.contains(it.next())) return true;
}
return false;
}
public static boolean containsAll(Collection a, Collection b) {
// fast paths
if (a == b) return true;
if (b.size() == 0) return true;
if (a.size() == 0) return false;
if (a instanceof SortedSet && b instanceof SortedSet) {
SortedSet aa = (SortedSet) a;
SortedSet bb = (SortedSet) b;
Comparator bbc = bb.comparator();
Comparator aac = aa.comparator();
if (bbc == null) {
if (aac == null) {
Iterator ai = aa.iterator();
Iterator bi = bb.iterator();
Comparable ao = (Comparable) ai.next(); // these are ok, since the sizes are != 0
Comparable bo = (Comparable) bi.next();
while (true) {
int rel = ao.compareTo(bo);
if (rel == 0) {
if (!bi.hasNext()) return true;
if (!ai.hasNext()) return false;
bo = (Comparable) bi.next();
ao = (Comparable) ai.next();
} else if (rel < 0) {
if (!ai.hasNext()) return false;
ao = (Comparable) ai.next();
} else {
return false;
}
}
}
} else if (bbc.equals(a)) {
Iterator ai = aa.iterator();
Iterator bi = bb.iterator();
Object ao = ai.next(); // these are ok, since the sizes are != 0
Object bo = bi.next();
while (true) {
int rel = aac.compare(ao, bo);
if (rel == 0) {
if (!bi.hasNext()) return true;
if (!ai.hasNext()) return false;
bo = bi.next();
ao = ai.next();
} else if (rel < 0) {
if (!ai.hasNext()) return false;
ao = ai.next();
} else {
return false;
}
}
}
}
return a.containsAll(b);
}
public static boolean containsNone(Collection a, Collection b) {
return !containsSome(a, b);
}
/**
* Used for results of getContainmentRelation
*/
public static final int
ALL_EMPTY = 0,
NOT_A_SUPERSET_B = 1,
NOT_A_DISJOINT_B = 2,
NOT_A_SUBSET_B = 4,
NOT_A_EQUALS_B = NOT_A_SUBSET_B | NOT_A_SUPERSET_B,
A_PROPER_SUBSET_OF_B = NOT_A_DISJOINT_B | NOT_A_SUPERSET_B,
A_PROPER_SUPERSET_B = NOT_A_SUBSET_B | NOT_A_DISJOINT_B,
A_PROPER_OVERLAPS_B = NOT_A_SUBSET_B | NOT_A_DISJOINT_B | NOT_A_SUPERSET_B;
/**
* Assesses all the possible containment relations between collections A and B with one call.<br>
* Returns an int with bits set, according to a "Venn Diagram" view of A vs B.<br>
* NOT_A_SUPERSET_B: a - b != {}<br>
* NOT_A_DISJOINT_B: a * b != {} // * is intersects<br>
* NOT_A_SUBSET_B: b - a != {}<br>
* Thus the bits can be used to get the following relations:<br>
* for A_SUPERSET_B, use (x & CollectionUtilities.NOT_A_SUPERSET_B) == 0<br>
* for A_SUBSET_B, use (x & CollectionUtilities.NOT_A_SUBSET_B) == 0<br>
* for A_EQUALS_B, use (x & CollectionUtilities.NOT_A_EQUALS_B) == 0<br>
* for A_DISJOINT_B, use (x & CollectionUtilities.NOT_A_DISJOINT_B) == 0<br>
* for A_OVERLAPS_B, use (x & CollectionUtilities.NOT_A_DISJOINT_B) != 0<br>
*/
public static int getContainmentRelation(Collection a, Collection b) {
if (a.size() == 0) {
return (b.size() == 0) ? ALL_EMPTY : NOT_A_SUPERSET_B;
} else if (b.size() == 0) {
return NOT_A_SUBSET_B;
}
int result = 0;
// WARNING: one might think that the following can be short-circuited, by looking at
// the sizes of a and b. However, this would fail in general, where a different comparator is being
// used in the two collections. Unfortunately, there is no failsafe way to test for that.
for (Iterator it = a.iterator(); result != 6 && it.hasNext();) {
result |= (b.contains(it.next())) ? NOT_A_DISJOINT_B : NOT_A_SUBSET_B;
}
for (Iterator it = b.iterator(); (result & 3) != 3 && it.hasNext();) {
result |= (a.contains(it.next())) ? NOT_A_DISJOINT_B : NOT_A_SUPERSET_B;
}
return result;
}
public static String remove(String source, UnicodeSet removals) {
StringBuffer result = new StringBuffer();
int cp;
for (int i = 0; i < source.length(); i += UTF16.getCharCount(cp)) {
cp = UTF16.charAt(source, i);
if (!removals.contains(cp)) UTF16.append(result, cp);
}
return result.toString();
}
//#ifndef FOUNDATION
//## /**
//## * Does one string contain another, starting at a specific offset?
//## * @param text
//## * @param offset
//## * @param other
//## * @return
//## */
//## public static int matchesAt(CharSequence text, int offset, CharSequence other) {
//## int len = other.length();
//## int i = 0;
//## int j = offset;
//## for (; i < len; ++i, ++j) {
//## char pc = other.charAt(i);
//## char tc = text.charAt(j);
//## if (pc != tc) return -1;
//## }
//## return i;
//## }
//##
//## /**
//## * Returns the ending offset found by matching characters with testSet, until a position is found that doen't match
//## * @param string
//## * @param offset
//## * @param testSet
//## * @return
//## */
//## public int span(CharSequence string, int offset, UnicodeSet testSet) {
//## while (true) {
//## int newOffset = testSet.matchesAt(string, offset);
//## if (newOffset < 0) return offset;
//## }
//## }
//##
//## /**
//## * Returns the ending offset found by matching characters with testSet, until a position is found that does match
//## * @param string
//## * @param offset
//## * @param testSet
//## * @return
//## */
//## public int spanNot(CharSequence string, int offset, UnicodeSet testSet) {
//## while (true) {
//## int newOffset = testSet.matchesAt(string, offset);
//## if (newOffset >= 0) return offset;
//## ++offset; // try next character position
//## // we don't have to worry about surrogates for this.
//## }
//## }
//#endif
public static String prettyPrint(UnicodeSet uset, boolean compressRanges, UnicodeSet toQuote, Transliterator quoter,
Comparator ordering, Comparator spaceComparator) {
PrettyPrinter pp = new PrettyPrinter().setCompressRanges(compressRanges);
if (toQuote != null) pp.setToQuote(toQuote);
if (ordering != null) pp.setOrdering(ordering);
if (spaceComparator != null) pp.setSpaceComparator(spaceComparator);
return pp.toPattern(uset);
}
public static class MultiComparator implements Comparator {
private Comparator[] comparators;
public MultiComparator (Comparator[] comparators) {
this.comparators = comparators;
}
/* Lexigraphic compare. Returns the first difference
* @return zero if equal. Otherwise +/- (i+1)
* where i is the index of the first comparator finding a difference
* @see java.util.Comparator#compare(java.lang.Object, java.lang.Object)
*/
public int compare(Object arg0, Object arg1) {
for (int i = 0; i < comparators.length; ++i) {
int result = comparators[i].compare(arg0, arg1);
if (result == 0) continue;
if (result > 0) return i+1;
return -(i+1);
}
return 0;
}
}
/**
* Modifies Unicode set to flatten the strings. Eg [abc{da}] => [abcd]
* Returns the set for chaining.
* @param exemplar1
* @return
*/
public static UnicodeSet flatten(UnicodeSet exemplar1) {
UnicodeSet result = new UnicodeSet();
boolean gotString = false;
for (UnicodeSetIterator it = new UnicodeSetIterator(exemplar1); it.nextRange();) {
if (it.codepoint == it.IS_STRING) {
result.addAll(it.string);
gotString = true;
} else {
result.add(it.codepoint, it.codepointEnd);
}
}
if (gotString) exemplar1.set(result);
return exemplar1;
}
/**
* For producing filtered iterators
*/
public static abstract class FilteredIterator implements Iterator {
private Iterator baseIterator;
private static final Object EMPTY = new Object();
private static final Object DONE = new Object();
private Object nextObject = EMPTY;
public FilteredIterator set(Iterator baseIterator) {
this.baseIterator = baseIterator;
return this;
}
public void remove() {
throw new UnsupportedOperationException("Doesn't support removal");
}
public Object next() {
Object result = nextObject;
nextObject = EMPTY;
return result;
}
public boolean hasNext() {
if (nextObject == DONE) return false;
if (nextObject != EMPTY) return true;
while (baseIterator.hasNext()) {
nextObject = baseIterator.next();
if (isIncluded(nextObject)) {
return true;
}
}
nextObject = DONE;
return false;
}
abstract public boolean isIncluded(Object item);
}
public static class PrefixIterator extends FilteredIterator {
private String prefix;
public PrefixIterator set(Iterator baseIterator, String prefix) {
super.set(baseIterator);
this.prefix = prefix;
return this;
}
public boolean isIncluded(Object item) {
return ((String)item).startsWith(prefix);
}
}
//#ifndef FOUNDATION
//## public static class RegexIterator extends FilteredIterator {
//## private Matcher matcher;
//## public RegexIterator set(Iterator baseIterator, Matcher matcher) {
//## super.set(baseIterator);
//## this.matcher = matcher;
//## return this;
//## }
//## public boolean isIncluded(Object item) {
//## return matcher.reset((String)item).matches();
//## }
//## }
//#endif
}