--- /dev/null
+package org.apache.lucene.analysis;
+
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import java.util.AbstractSet;
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.Set;
+
+import org.apache.lucene.util.Version;
+
+/**
+ * A simple class that stores Strings as char[]'s in a
+ * hash table. Note that this is not a general purpose
+ * class. For example, it cannot remove items from the
+ * set, nor does it resize its hash table to be smaller,
+ * etc. It is designed to be quick to test if a char[]
+ * is in the set without the necessity of converting it
+ * to a String first.
+ * <p>You must specify the required {@link Version}
+ * compatibility when creating {@link CharArraySet}:
+ * <ul>
+ * <li> As of 3.1, supplementary characters are
+ * properly lowercased.</li>
+ * </ul>
+ * Before 3.1 supplementary characters could not be
+ * lowercased correctly due to the lack of Unicode 4
+ * support in JDK 1.4. To use instances of
+ * {@link CharArraySet} with the behavior before Lucene
+ * 3.1 pass a {@link Version} < 3.1 to the constructors.
+ * <P>
+ * <em>Please note:</em> This class implements {@link java.util.Set Set} but
+ * does not behave like it should in all cases. The generic type is
+ * {@code Set<Object>}, because you can add any object to it,
+ * that has a string representation. The add methods will use
+ * {@link Object#toString} and store the result using a {@code char[]}
+ * buffer. The same behavior have the {@code contains()} methods.
+ * The {@link #iterator()} returns an {@code Iterator<String>}.
+ * For type safety also {@link #stringIterator()} is provided.
+ */
+public class CharArraySet extends AbstractSet<Object> {
+ public static final CharArraySet EMPTY_SET = new CharArraySet(CharArrayMap.<Object>emptyMap());
+ private static final Object PLACEHOLDER = new Object();
+
+ private final CharArrayMap<Object> map;
+
+ /**
+ * Create set with enough capacity to hold startSize terms
+ *
+ * @param matchVersion
+ * compatibility match version see <a href="#version">Version
+ * note</a> above for details.
+ * @param startSize
+ * the initial capacity
+ * @param ignoreCase
+ * <code>false</code> if and only if the set should be case sensitive
+ * otherwise <code>true</code>.
+ */
+ public CharArraySet(Version matchVersion, int startSize, boolean ignoreCase) {
+ this(new CharArrayMap<Object>(matchVersion, startSize, ignoreCase));
+ }
+
+ /**
+ * Creates a set from a Collection of objects.
+ *
+ * @param matchVersion
+ * compatibility match version see <a href="#version">Version
+ * note</a> above for details.
+ * @param c
+ * a collection whose elements to be placed into the set
+ * @param ignoreCase
+ * <code>false</code> if and only if the set should be case sensitive
+ * otherwise <code>true</code>.
+ */
+ public CharArraySet(Version matchVersion, Collection<?> c, boolean ignoreCase) {
+ this(matchVersion, c.size(), ignoreCase);
+ addAll(c);
+ }
+
+ /**
+ * Creates a set with enough capacity to hold startSize terms
+ *
+ * @param startSize
+ * the initial capacity
+ * @param ignoreCase
+ * <code>false</code> if and only if the set should be case sensitive
+ * otherwise <code>true</code>.
+ * @deprecated use {@link #CharArraySet(Version, int, boolean)} instead
+ */
+ @Deprecated
+ public CharArraySet(int startSize, boolean ignoreCase) {
+ this(Version.LUCENE_30, startSize, ignoreCase);
+ }
+
+ /**
+ * Creates a set from a Collection of objects.
+ *
+ * @param c
+ * a collection whose elements to be placed into the set
+ * @param ignoreCase
+ * <code>false</code> if and only if the set should be case sensitive
+ * otherwise <code>true</code>.
+ * @deprecated use {@link #CharArraySet(Version, Collection, boolean)} instead
+ */
+ @Deprecated
+ public CharArraySet(Collection<?> c, boolean ignoreCase) {
+ this(Version.LUCENE_30, c.size(), ignoreCase);
+ addAll(c);
+ }
+
+ /** Create set from the specified map (internal only), used also by {@link CharArrayMap#keySet()} */
+ CharArraySet(final CharArrayMap<Object> map){
+ this.map = map;
+ }
+
+ /** Clears all entries in this set. This method is supported for reusing, but not {@link Set#remove}. */
+ @Override
+ public void clear() {
+ map.clear();
+ }
+
+ /** true if the <code>len</code> chars of <code>text</code> starting at <code>off</code>
+ * are in the set */
+ public boolean contains(char[] text, int off, int len) {
+ return map.containsKey(text, off, len);
+ }
+
+ /** true if the <code>CharSequence</code> is in the set */
+ public boolean contains(CharSequence cs) {
+ return map.containsKey(cs);
+ }
+
+ @Override
+ public boolean contains(Object o) {
+ return map.containsKey(o);
+ }
+
+ @Override
+ public boolean add(Object o) {
+ return map.put(o, PLACEHOLDER) == null;
+ }
+
+ /** Add this CharSequence into the set */
+ public boolean add(CharSequence text) {
+ return map.put(text, PLACEHOLDER) == null;
+ }
+
+ /** Add this String into the set */
+ public boolean add(String text) {
+ return map.put(text, PLACEHOLDER) == null;
+ }
+
+ /** Add this char[] directly to the set.
+ * If ignoreCase is true for this Set, the text array will be directly modified.
+ * The user should never modify this text array after calling this method.
+ */
+ public boolean add(char[] text) {
+ return map.put(text, PLACEHOLDER) == null;
+ }
+
+ @Override
+ public int size() {
+ return map.size();
+ }
+
+ /**
+ * Returns an unmodifiable {@link CharArraySet}. This allows to provide
+ * unmodifiable views of internal sets for "read-only" use.
+ *
+ * @param set
+ * a set for which the unmodifiable set is returned.
+ * @return an new unmodifiable {@link CharArraySet}.
+ * @throws NullPointerException
+ * if the given set is <code>null</code>.
+ */
+ public static CharArraySet unmodifiableSet(CharArraySet set) {
+ if (set == null)
+ throw new NullPointerException("Given set is null");
+ if (set == EMPTY_SET)
+ return EMPTY_SET;
+ if (set.map instanceof CharArrayMap.UnmodifiableCharArrayMap)
+ return set;
+ return new CharArraySet(CharArrayMap.unmodifiableMap(set.map));
+ }
+
+ /**
+ * Returns a copy of the given set as a {@link CharArraySet}. If the given set
+ * is a {@link CharArraySet} the ignoreCase property will be preserved.
+ *
+ * @param set
+ * a set to copy
+ * @return a copy of the given set as a {@link CharArraySet}. If the given set
+ * is a {@link CharArraySet} the ignoreCase and matchVersion property will be
+ * preserved.
+ * @deprecated use {@link #copy(Version, Set)} instead.
+ */
+ @Deprecated
+ public static CharArraySet copy(final Set<?> set) {
+ if(set == EMPTY_SET)
+ return EMPTY_SET;
+ return copy(Version.LUCENE_30, set);
+ }
+
+ /**
+ * Returns a copy of the given set as a {@link CharArraySet}. If the given set
+ * is a {@link CharArraySet} the ignoreCase property will be preserved.
+ * <p>
+ * <b>Note:</b> If you intend to create a copy of another {@link CharArraySet} where
+ * the {@link Version} of the source set differs from its copy
+ * {@link #CharArraySet(Version, Collection, boolean)} should be used instead.
+ * The {@link #copy(Version, Set)} will preserve the {@link Version} of the
+ * source set it is an instance of {@link CharArraySet}.
+ * </p>
+ *
+ * @param matchVersion
+ * compatibility match version see <a href="#version">Version
+ * note</a> above for details. This argument will be ignored if the
+ * given set is a {@link CharArraySet}.
+ * @param set
+ * a set to copy
+ * @return a copy of the given set as a {@link CharArraySet}. If the given set
+ * is a {@link CharArraySet} the ignoreCase property as well as the
+ * matchVersion will be of the given set will be preserved.
+ */
+ public static CharArraySet copy(final Version matchVersion, final Set<?> set) {
+ if(set == EMPTY_SET)
+ return EMPTY_SET;
+ if(set instanceof CharArraySet) {
+ final CharArraySet source = (CharArraySet) set;
+ return new CharArraySet(CharArrayMap.copy(source.map.matchVersion, source.map));
+ }
+ return new CharArraySet(matchVersion, set, false);
+ }
+
+ /** The Iterator<String> for this set. Strings are constructed on the fly, so
+ * use <code>nextCharArray</code> for more efficient access.
+ * @deprecated Use the standard iterator, which returns {@code char[]} instances.
+ */
+ @Deprecated
+ public class CharArraySetIterator implements Iterator<String> {
+ int pos=-1;
+ char[] next;
+ private CharArraySetIterator() {
+ goNext();
+ }
+
+ private void goNext() {
+ next = null;
+ pos++;
+ while (pos < map.keys.length && (next=map.keys[pos]) == null) pos++;
+ }
+
+ public boolean hasNext() {
+ return next != null;
+ }
+
+ /** do not modify the returned char[] */
+ public char[] nextCharArray() {
+ char[] ret = next;
+ goNext();
+ return ret;
+ }
+
+ /** Returns the next String, as a Set<String> would...
+ * use nextCharArray() for better efficiency. */
+ public String next() {
+ return new String(nextCharArray());
+ }
+
+ public void remove() {
+ throw new UnsupportedOperationException();
+ }
+ }
+
+ /** returns an iterator of new allocated Strings (an instance of {@link CharArraySetIterator}).
+ * @deprecated Use {@link #iterator}, which returns {@code char[]} instances.
+ */
+ @Deprecated
+ public Iterator<String> stringIterator() {
+ return new CharArraySetIterator();
+ }
+
+ /** Returns an {@link Iterator} depending on the version used:
+ * <ul>
+ * <li>if {@code matchVersion} ≥ 3.1, it returns {@code char[]} instances in this set.</li>
+ * <li>if {@code matchVersion} is 3.0 or older, it returns new
+ * allocated Strings, so this method violates the Set interface.
+ * It is kept this way for backwards compatibility, normally it should
+ * return {@code char[]} on {@code next()}</li>
+ * </ul>
+ */
+ @Override @SuppressWarnings("unchecked")
+ public Iterator<Object> iterator() {
+ // use the AbstractSet#keySet()'s iterator (to not produce endless recursion)
+ return map.matchVersion.onOrAfter(Version.LUCENE_31) ?
+ map.originalKeySet().iterator() : (Iterator) stringIterator();
+ }
+
+ @Override
+ public String toString() {
+ final StringBuilder sb = new StringBuilder("[");
+ for (Object item : this) {
+ if (sb.length()>1) sb.append(", ");
+ if (item instanceof char[]) {
+ sb.append((char[]) item);
+ } else {
+ sb.append(item);
+ }
+ }
+ return sb.append(']').toString();
+ }
+}
fnp / pylucene.git / blobdiff