--- /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.io.IOException;
+import java.io.Reader;
+
+import org.apache.lucene.analysis.tokenattributes.OffsetAttribute;
+import org.apache.lucene.analysis.tokenattributes.CharTermAttribute;
+import org.apache.lucene.util.AttributeSource;
+import org.apache.lucene.util.CharacterUtils;
+import org.apache.lucene.util.Version;
+import org.apache.lucene.util.VirtualMethod;
+import org.apache.lucene.util.CharacterUtils.CharacterBuffer;
+
+/**
+ * An abstract base class for simple, character-oriented tokenizers.
+ * <p>
+ * <a name="version">You must specify the required {@link Version} compatibility
+ * when creating {@link CharTokenizer}:
+ * <ul>
+ * <li>As of 3.1, {@link CharTokenizer} uses an int based API to normalize and
+ * detect token codepoints. See {@link #isTokenChar(int)} and
+ * {@link #normalize(int)} for details.</li>
+ * </ul>
+ * <p>
+ * A new {@link CharTokenizer} API has been introduced with Lucene 3.1. This API
+ * moved from UTF-16 code units to UTF-32 codepoints to eventually add support
+ * for <a href=
+ * "http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Character.html#supplementary"
+ * >supplementary characters</a>. The old <i>char</i> based API has been
+ * deprecated and should be replaced with the <i>int</i> based methods
+ * {@link #isTokenChar(int)} and {@link #normalize(int)}.
+ * </p>
+ * <p>
+ * As of Lucene 3.1 each {@link CharTokenizer} - constructor expects a
+ * {@link Version} argument. Based on the given {@link Version} either the new
+ * API or a backwards compatibility layer is used at runtime. For
+ * {@link Version} < 3.1 the backwards compatibility layer ensures correct
+ * behavior even for indexes build with previous versions of Lucene. If a
+ * {@link Version} >= 3.1 is used {@link CharTokenizer} requires the new API to
+ * be implemented by the instantiated class. Yet, the old <i>char</i> based API
+ * is not required anymore even if backwards compatibility must be preserved.
+ * {@link CharTokenizer} subclasses implementing the new API are fully backwards
+ * compatible if instantiated with {@link Version} < 3.1.
+ * </p>
+ * <p>
+ * <strong>Note:</strong> If you use a subclass of {@link CharTokenizer} with {@link Version} >=
+ * 3.1 on an index build with a version < 3.1, created tokens might not be
+ * compatible with the terms in your index.
+ * </p>
+ **/
+public abstract class CharTokenizer extends Tokenizer {
+
+ /**
+ * Creates a new {@link CharTokenizer} instance
+ *
+ * @param matchVersion
+ * Lucene version to match See {@link <a href="#version">above</a>}
+ * @param input
+ * the input to split up into tokens
+ */
+ public CharTokenizer(Version matchVersion, Reader input) {
+ super(input);
+ charUtils = CharacterUtils.getInstance(matchVersion);
+ useOldAPI = useOldAPI(matchVersion);
+
+ }
+
+ /**
+ * Creates a new {@link CharTokenizer} instance
+ *
+ * @param matchVersion
+ * Lucene version to match See {@link <a href="#version">above</a>}
+ * @param source
+ * the attribute source to use for this {@link Tokenizer}
+ * @param input
+ * the input to split up into tokens
+ */
+ public CharTokenizer(Version matchVersion, AttributeSource source,
+ Reader input) {
+ super(source, input);
+ charUtils = CharacterUtils.getInstance(matchVersion);
+ useOldAPI = useOldAPI(matchVersion);
+ }
+
+ /**
+ * Creates a new {@link CharTokenizer} instance
+ *
+ * @param matchVersion
+ * Lucene version to match See {@link <a href="#version">above</a>}
+ * @param factory
+ * the attribute factory to use for this {@link Tokenizer}
+ * @param input
+ * the input to split up into tokens
+ */
+ public CharTokenizer(Version matchVersion, AttributeFactory factory,
+ Reader input) {
+ super(factory, input);
+ charUtils = CharacterUtils.getInstance(matchVersion);
+ useOldAPI = useOldAPI(matchVersion);
+ }
+
+ /**
+ * Creates a new {@link CharTokenizer} instance
+ * @param input the input to split up into tokens
+ * @deprecated use {@link #CharTokenizer(Version, Reader)} instead. This will be
+ * removed in Lucene 4.0.
+ */
+ @Deprecated
+ public CharTokenizer(Reader input) {
+ this(Version.LUCENE_30, input);
+ }
+
+ /**
+ * Creates a new {@link CharTokenizer} instance
+ * @param input the input to split up into tokens
+ * @param source the attribute source to use for this {@link Tokenizer}
+ * @deprecated use {@link #CharTokenizer(Version, AttributeSource, Reader)} instead. This will be
+ * removed in Lucene 4.0.
+ */
+ @Deprecated
+ public CharTokenizer(AttributeSource source, Reader input) {
+ this(Version.LUCENE_30, source, input);
+ }
+
+ /**
+ * Creates a new {@link CharTokenizer} instance
+ * @param input the input to split up into tokens
+ * @param factory the attribute factory to use for this {@link Tokenizer}
+ * @deprecated use {@link #CharTokenizer(Version, AttributeSource.AttributeFactory, Reader)} instead. This will be
+ * removed in Lucene 4.0.
+ */
+ @Deprecated
+ public CharTokenizer(AttributeFactory factory, Reader input) {
+ this(Version.LUCENE_30, factory, input);
+ }
+
+ private int offset = 0, bufferIndex = 0, dataLen = 0, finalOffset = 0;
+ private static final int MAX_WORD_LEN = 255;
+ private static final int IO_BUFFER_SIZE = 4096;
+
+ private final CharTermAttribute termAtt = addAttribute(CharTermAttribute.class);;
+ private final OffsetAttribute offsetAtt = addAttribute(OffsetAttribute.class);
+
+ private final CharacterUtils charUtils;
+ private final CharacterBuffer ioBuffer = CharacterUtils.newCharacterBuffer(IO_BUFFER_SIZE);
+
+ /**
+ * @deprecated this will be removed in lucene 4.0
+ */
+ @Deprecated
+ private final boolean useOldAPI;
+
+ /**
+ * @deprecated this will be removed in lucene 4.0
+ */
+ @Deprecated
+ private static final VirtualMethod<CharTokenizer> isTokenCharMethod =
+ new VirtualMethod<CharTokenizer>(CharTokenizer.class, "isTokenChar", char.class);
+
+ /**
+ * @deprecated this will be removed in lucene 4.0
+ */
+ @Deprecated
+ private static final VirtualMethod<CharTokenizer> normalizeMethod =
+ new VirtualMethod<CharTokenizer>(CharTokenizer.class, "normalize", char.class);
+
+ /**
+ * Returns true iff a UTF-16 code unit should be included in a token. This
+ * tokenizer generates as tokens adjacent sequences of characters which
+ * satisfy this predicate. Characters for which this is <code>false</code> are
+ * used to define token boundaries and are not included in tokens.
+ * <p>
+ * Note: This method cannot handle <a href=
+ * "http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Character.html#supplementary"
+ * >supplementary characters</a>. To support all Unicode characters, including
+ * supplementary characters, use the {@link #isTokenChar(int)} method.
+ * </p>
+ *
+ * @deprecated use {@link #isTokenChar(int)} instead. This method will be
+ * removed in Lucene 4.0.
+ */
+ @Deprecated
+ protected boolean isTokenChar(char c) {
+ return isTokenChar((int)c);
+ }
+
+ /**
+ * Called on each token UTF-16 code unit to normalize it before it is added to the
+ * token. The default implementation does nothing. Subclasses may use this to,
+ * e.g., lowercase tokens.
+ * <p>
+ * Note: This method cannot handle <a href=
+ * "http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Character.html#supplementary"
+ * >supplementary characters</a>. To support all Unicode characters, including
+ * supplementary characters, use the {@link #normalize(int)} method.
+ * </p>
+ *
+ * @deprecated use {@link #normalize(int)} instead. This method will be
+ * removed in Lucene 4.0.
+ */
+ @Deprecated
+ protected char normalize(char c) {
+ return (char) normalize((int) c);
+ }
+
+ /**
+ * Returns true iff a codepoint should be included in a token. This tokenizer
+ * generates as tokens adjacent sequences of codepoints which satisfy this
+ * predicate. Codepoints for which this is false are used to define token
+ * boundaries and are not included in tokens.
+ * <p>
+ * As of Lucene 3.1 the char based API ({@link #isTokenChar(char)} and
+ * {@link #normalize(char)}) has been depreciated in favor of a Unicode 4.0
+ * compatible int based API to support codepoints instead of UTF-16 code
+ * units. Subclasses of {@link CharTokenizer} must not override the char based
+ * methods if a {@link Version} >= 3.1 is passed to the constructor.
+ * <p>
+ * <p>
+ * NOTE: This method will be marked <i>abstract</i> in Lucene 4.0.
+ * </p>
+ */
+ protected boolean isTokenChar(int c) {
+ throw new UnsupportedOperationException("since LUCENE_31 subclasses of CharTokenizer must implement isTokenChar(int)");
+ }
+
+ /**
+ * Called on each token character to normalize it before it is added to the
+ * token. The default implementation does nothing. Subclasses may use this to,
+ * e.g., lowercase tokens.
+ * <p>
+ * As of Lucene 3.1 the char based API ({@link #isTokenChar(char)} and
+ * {@link #normalize(char)}) has been depreciated in favor of a Unicode 4.0
+ * compatible int based API to support codepoints instead of UTF-16 code
+ * units. Subclasses of {@link CharTokenizer} must not override the char based
+ * methods if a {@link Version} >= 3.1 is passed to the constructor.
+ * <p>
+ * <p>
+ * NOTE: This method will be marked <i>abstract</i> in Lucene 4.0.
+ * </p>
+ */
+ protected int normalize(int c) {
+ return c;
+ }
+
+ @Override
+ public final boolean incrementToken() throws IOException {
+ clearAttributes();
+ if(useOldAPI) // TODO remove this in LUCENE 4.0
+ return incrementTokenOld();
+ int length = 0;
+ int start = -1; // this variable is always initialized
+ char[] buffer = termAtt.buffer();
+ while (true) {
+ if (bufferIndex >= dataLen) {
+ offset += dataLen;
+ if(!charUtils.fill(ioBuffer, input)) { // read supplementary char aware with CharacterUtils
+ dataLen = 0; // so next offset += dataLen won't decrement offset
+ if (length > 0) {
+ break;
+ } else {
+ finalOffset = correctOffset(offset);
+ return false;
+ }
+ }
+ dataLen = ioBuffer.getLength();
+ bufferIndex = 0;
+ }
+ // use CharacterUtils here to support < 3.1 UTF-16 code unit behavior if the char based methods are gone
+ final int c = charUtils.codePointAt(ioBuffer.getBuffer(), bufferIndex);
+ bufferIndex += Character.charCount(c);
+
+ if (isTokenChar(c)) { // if it's a token char
+ if (length == 0) { // start of token
+ assert start == -1;
+ start = offset + bufferIndex - 1;
+ } else if (length >= buffer.length-1) { // check if a supplementary could run out of bounds
+ buffer = termAtt.resizeBuffer(2+length); // make sure a supplementary fits in the buffer
+ }
+ length += Character.toChars(normalize(c), buffer, length); // buffer it, normalized
+ if (length >= MAX_WORD_LEN) // buffer overflow! make sure to check for >= surrogate pair could break == test
+ break;
+ } else if (length > 0) // at non-Letter w/ chars
+ break; // return 'em
+ }
+
+ termAtt.setLength(length);
+ assert start != -1;
+ offsetAtt.setOffset(correctOffset(start), finalOffset = correctOffset(start+length));
+ return true;
+
+ }
+
+ /**
+ * The <= 3.0 version of incrementToken. This is a backwards compat implementation used
+ * if a version <= 3.0 is provided to the ctor.
+ * @deprecated remove in 4.0
+ */
+ @Deprecated
+ private boolean incrementTokenOld() throws IOException {
+ int length = 0;
+ int start = -1; // this variable is always initialized
+ char[] buffer = termAtt.buffer();
+ final char[] oldIoBuffer = ioBuffer.getBuffer();
+ while (true) {
+
+ if (bufferIndex >= dataLen) {
+ offset += dataLen;
+ dataLen = input.read(oldIoBuffer);
+ if (dataLen == -1) {
+ dataLen = 0; // so next offset += dataLen won't decrement offset
+ if (length > 0) {
+ break;
+ } else {
+ finalOffset = correctOffset(offset);
+ return false;
+ }
+ }
+ bufferIndex = 0;
+ }
+
+ final char c = oldIoBuffer[bufferIndex++];
+
+ if (isTokenChar(c)) { // if it's a token char
+
+ if (length == 0) { // start of token
+ assert start == -1;
+ start = offset + bufferIndex - 1;
+ } else if (length == buffer.length) {
+ buffer = termAtt.resizeBuffer(1+length);
+ }
+
+ buffer[length++] = normalize(c); // buffer it, normalized
+
+ if (length == MAX_WORD_LEN) // buffer overflow!
+ break;
+
+ } else if (length > 0) // at non-Letter w/ chars
+ break; // return 'em
+ }
+
+ termAtt.setLength(length);
+ assert start != -1;
+ offsetAtt.setOffset(correctOffset(start), correctOffset(start+length));
+ return true;
+ }
+
+
+
+ @Override
+ public final void end() {
+ // set final offset
+ offsetAtt.setOffset(finalOffset, finalOffset);
+ }
+
+ @Override
+ public void reset(Reader input) throws IOException {
+ super.reset(input);
+ bufferIndex = 0;
+ offset = 0;
+ dataLen = 0;
+ finalOffset = 0;
+ ioBuffer.reset(); // make sure to reset the IO buffer!!
+ }
+
+ /**
+ * @deprecated this will be removed in lucene 4.0
+ */
+ @Deprecated
+ private boolean useOldAPI(Version matchVersion) {
+ final Class<? extends CharTokenizer> clazz = this.getClass();
+ if (matchVersion.onOrAfter(Version.LUCENE_31)
+ && (isTokenCharMethod.isOverriddenAsOf(clazz) || normalizeMethod
+ .isOverriddenAsOf(clazz))) throw new IllegalArgumentException(
+ "For matchVersion >= LUCENE_31, CharTokenizer subclasses must not override isTokenChar(char) or normalize(char).");
+ return !matchVersion.onOrAfter(Version.LUCENE_31);
+ }
+}
\ No newline at end of file
fnp / pylucene.git / blobdiff