importer.filters.Filter.java Source code

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Here is the source code for importer.filters.Filter.java

Source

/*
 * This file is part of Importer.
 *
 *  Importer is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  Importer is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with Importer.  If not, see <http://www.gnu.org/licenses/>.
 *  (c) copyright Desmond Schmidt 2015
 */

package importer.filters;

import importer.Archive;
import importer.exception.ImporterException;
import calliope.AeseSpeller;
import java.io.CharArrayWriter;
import java.io.IOException;
import java.util.HashSet;
import org.json.simple.JSONObject;

/**
 * Specify how filters interact with the outside world
 * @author desmond
 */
public abstract class Filter {
    protected MarkupSet markup;
    protected String dict;
    protected String hhExceptions;
    protected AeseSpeller speller;
    protected boolean lastEndsInHyphen;
    protected HashSet<String> compounds;
    protected int written;
    protected char[] CR = { '\n' };
    protected char[] HYPHEN = { '-' };
    protected char[] SPACE = { ' ' };
    protected char[] EMPTY = {};
    protected String ENC = "UTF-8";

    public Filter() {
        this.dict = "en_GB";
        this.markup = new MarkupSet();
        this.hhExceptions = "";
        try {
            this.speller = new AeseSpeller(dict);
            this.compounds = new HashSet<String>();
            if (hhExceptions != null && hhExceptions.length() > 0) {
                String[] items = hhExceptions.split("\n");
                for (int i = 0; i < items.length; i++)
                    compounds.add(items[i]);
            }
        } catch (Exception e1) {
            try {
                this.speller = new AeseSpeller("en_GB");
            } catch (Exception e2) {
            }
        }
    }

    /**
     * Set the encoding used for serialisation. This should be the MVD's 
     * internal encoding. Can be anything.     
     * @param encoding the encoding, defaults to UTF-8
     */
    public void setEncoding(String encoding) {
        ENC = encoding;
    }

    /**
     * We really should cleanup the speller before we go
     */
    protected void finalize() {
        if (this.speller != null)
            this.speller.cleanup();
    }

    protected void writeCurrent(CharArrayWriter txt, char[] current) throws IOException {
        txt.write(current);
        written += current.length;
    }

    /**
     * Should we hard-hyphenate two words or part-words?
     * @param last the previous 'word'
     * @param next the word on the next line
     * @return true for a hard hyphen else soft
     */
    public boolean isHardHyphen(String last, String next) {
        String compound = last + next;
        if (last.equals("--"))
            return true;
        else if (speller.hasWord(last, dict) && speller.hasWord(next, dict)
                && (!speller.hasWord(compound, dict) || compounds.contains(compound)))
            return true;
        else
            return false;
    }

    public void setDict(String dict) {
        this.dict = dict;
    }

    public void setHHExceptions(String hhExceptions) {
        this.hhExceptions = hhExceptions;
    }

    /**
     * Get the raw name of this filter e.g. "play"
     * @return the filter name
     * @throws AeseException 
     */
    public String getName() throws ImporterException {
        String className = this.getClass().getSimpleName();
        int pos = className.indexOf("Filter");
        if (pos != -1)
            return className.substring(0, pos);
        else
            throw new ImporterException("invalid class name: " + className);
    }

    /**
     * Get the first word of a line
     * @param line the line in question
     * @return 
     */
    protected String getFirstWord(String line) {
        int i;
        int len = line.length();
        for (i = 0; i < line.length(); i++) {
            if (!Character.isWhitespace(line.charAt(i)))
                break;
        }
        int j = i;
        for (; i < len; i++) {
            if (!Character.isLetter(line.charAt(i)) || line.charAt(i) == '-')
                break;
        }
        return line.substring(j, i);
    }

    /**
     * Get the last word of a line excluding punctuation etc
     * @param line the line in question
     * @return the word
     */
    protected String getLastWord(String text) {
        int len = text.length();
        if (len > 0) {
            int start = 0;
            int size = 0, i = len - 1;
            // point beyond trailing hyphen
            if (len > 1 && text.endsWith("--")) {
                lastEndsInHyphen = true;
                return "--";
            } else if (text.charAt(len - 1) == '-') {
                lastEndsInHyphen = true;
                len--;
                i--;
            } else {
                lastEndsInHyphen = false;
                // point to last non-space
                for (; i > 0; i--) {
                    if (!Character.isWhitespace(text.charAt(i)))
                        break;
                }
            }
            int j = i;
            for (; i > 0; i--) {
                if (!Character.isLetter(text.charAt(i))) {
                    start = i + 1;
                    size = j - i;
                    break;
                }
            }
            if (i == 0)
                size = (j - i) + 1;
            return text.substring(start, start + size);
        } else
            return "";
    }

    /**
     * Reinitialise for a new conversion
     */
    protected void init() {
        written = 0;
        markup.clear();
    }

    public abstract void configure(JSONObject config);

    /**
     * Short description of this filter
     * @return a string
     */
    public abstract String getDescription();

    /**
     * Subclasses should override this
     * @param input the input text for conversion
     * @param name the name of the new version
     * @param cortex the cortex archive to save filtered text in
     * @param corcode the corcode archive to save the inferred markup in
     * @return the log output
     */
    public abstract String convert(String input, String name, Archive cortex, Archive corcode)
            throws ImporterException;
}