com.groupbyinc.common.apache.commons.text.similarity.RegexTokenizer Maven / Gradle / Ivy
/*
* 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.
*/
package org.apache.commons.text.similarity;
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.Validate;
/**
* A simple word tokenizer that utilizes regex to find words. It applies a regex
* {@code}(\w)+{@code} over the input text to extract words from a given character
* sequence.
*
* @since 1.0
*/
class RegexTokenizer implements Tokenizer {
/**
* {@inheritDoc}
*
* @throws IllegalArgumentException if the input text is blank
*/
@Override
public CharSequence[] tokenize(final CharSequence text) {
Validate.isTrue(StringUtils.isNotBlank(text), "Invalid text");
final Pattern pattern = Pattern.compile("(\\w)+");
final Matcher matcher = pattern.matcher(text.toString());
final List tokens = new ArrayList<>();
while (matcher.find()) {
tokens.add(matcher.group(0));
}
return tokens.toArray(new String[0]);
}
}