io.dataapps.chlorine.pattern.RegexFinder.java Source code

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Here is the source code for io.dataapps.chlorine.pattern.RegexFinder.java

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/*
 * Copyright 2016, DataApps Corporation (http://dataApps.io) .
 * 
 * Licensed 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 io.dataapps.chlorine.pattern;

import io.dataapps.chlorine.finder.Finder;
import io.dataapps.chlorine.finder.FinderResult;

import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

public class RegexFinder implements Finder {
    static final Log LOG = LogFactory.getLog(RegexFinder.class);
    public static final int DEFAULT_FLAGS = Pattern.CANON_EQ | Pattern.CASE_INSENSITIVE | Pattern.MULTILINE;

    private String name;
    Pattern pattern;

    public RegexFinder() {
    }

    /**
     * Construct a Regular expression Based Finder using a pattern and default flags.
     * @param name - name of the Finder
     * @param pattern - pattern of the regular expression.
     */
    public RegexFinder(String name, String pattern) {
        this(name, pattern, DEFAULT_FLAGS);
    }

    /**
     * Construct a Regular expression Based Finder using pattern and flags.
     * @param name - name of the Finder
     * @param pattern - pattern of the regular expression.
     * @param flags - Flags to be used while compiling the pattern.
     */
    public RegexFinder(String name, String pattern, int flags) {
        this.name = name;
        this.pattern = Pattern.compile(pattern, flags);
    }

    /**
     * set the name of the Finder
     * @param name
     */
    public void setName(String name) {
        this.name = name;
    }

    /**
     * get Finder's name.
     */
    public String getName() {
        return name;
    }

    /**
     * set the Pattern
     * @param pattern
     */
    public void setPattern(Pattern pattern) {
        this.pattern = pattern;
    }

    /**
     * Get Pattern.
     */
    public Pattern getPattern() {
        return pattern;
    }

    /**
     * Scan the list of inputs using the finders.
     * Return a list of actual matched values.
     * @return a list of matches 
     */
    public FinderResult find(String input) {
        List<String> matches = new ArrayList<>();
        Matcher matcher = pattern.matcher(input);
        while (matcher.find()) {
            matches.add(input.substring(matcher.start(), matcher.end()));
        }
        return new FinderResult(matches, replace(input, ""));
    }

    static String removeCommas(String match) {
        if (match.endsWith(",")) {
            match = match.substring(0, match.length() - 1);
        }
        if (match.startsWith(",")) {
            match = match.substring(1);
        }
        return match;
    }

    private String replace(String input, String replacement) {
        Matcher matcher = pattern.matcher(input);
        return matcher.replaceAll(replacement);
    }

}