Application: gvSIG desktop

package org.gvsig.fmap.dal.store.csv.simplereaders;

import java.io.IOException;

import java.io.InputStreamReader;

import java.util.List;

import org.apache.commons.lang3.StringUtils;

import org.gvsig.fmap.dal.store.csv.CSVStoreParameters;

import org.gvsig.tools.dynobject.DynObject;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.supercsv.comment.CommentStartsWith;

import org.supercsv.io.CsvListReader;

import org.supercsv.prefs.CsvPreference;

import org.supercsv.quote.QuoteMode;

public class CSVReader implements SimpleReader {

    //

    // http://supercsv.sourceforge.net/examples_reading.html

    // http://supercsv.sourceforge.net/apidocs/index.html

    //

    private static final Logger logger = LoggerFactory.getLogger(CSVReader.class);

    private CsvListReader reader;

    private final CSVStoreParameters parameters;

    private List<String>  nextLine;

    private int columns;

    public CSVReader(InputStreamReader in, CSVStoreParameters parameters) {

        this(parameters);

        this.reader = new CsvListReader(in, getCSVPreferences());

    }    

    public CSVReader(CSVStoreParameters parameters) {

        this.reader = null;

        this.parameters = parameters;

        this.reader = null;

        this.nextLine = null;

        this.columns = 0;

    }

    public CSVStoreParameters getParameters() {

        return this.parameters;

    }

    @Override

    public String[] getHeader() throws IOException {

        return this.reader.getHeader(true);

    }

    @Override

    public int getColumnsCount() throws IOException {

        if( this.columns <= 0 ) {

            this.columns = reader.length();

            if( this.columns <= 0 ) {

                this.nextLine = this.reader.read();

                this.columns = reader.length();

            }

        }

        return this.columns;

    }

    @Override

    public List<String> read() throws IOException {

        List<String> line;

        if( this.nextLine != null ) {

            line = this.nextLine;

            this.nextLine = null;

        } else {

            line = this.reader.read();

        }

        return line;

    }

    @Override

    public void close() throws IOException {

        this.reader.close();

    }

    @Override

    public List<String> skip(int lines) throws IOException {

        if( lines <= 0 ) {

            return null;

        }

        if( this.nextLine != null ) {

            this.nextLine = null;

            lines--;

        }

        List<String> row = null;

        for ( int i = 0; i < lines; i++ ) {

            row = reader.read();

        }

        return row;

    }

    public CsvPreference getCSVPreferences() {

        try {

            String s;

            char quoteChar;

            int delimiterChar;

            String endOfLineSymbols;

            DynObject params = this.getParameters();

            CsvPreference.Builder builder;

            CsvPreference defaultPreference = CSVStoreParameters

                    .getPredefinedCSVPreferences(params);

            if ( defaultPreference == null ) {

                defaultPreference = CsvPreference.STANDARD_PREFERENCE;

            }

            endOfLineSymbols = CSVStoreParameters.getRecordSeparator(params);

            if ( StringUtils.isBlank(endOfLineSymbols) ) {

                endOfLineSymbols = defaultPreference.getEndOfLineSymbols();

            }

            s = CSVStoreParameters.getQuoteCharacter(params);

            if ( StringUtils.isBlank(s) ) {

                quoteChar = (char) defaultPreference.getQuoteChar();

            } else {

                quoteChar = s.charAt(0);

            }

            s = CSVStoreParameters.getDelimiter(params);

            if ( StringUtils.isBlank(s) ) {

                delimiterChar = defaultPreference.getDelimiterChar();

            } else {

                delimiterChar = s.charAt(0);

            }

            builder = new CsvPreference.Builder(quoteChar, delimiterChar,

                    endOfLineSymbols);

            s = CSVStoreParameters.getCommentStartMarker(params);

            if ( !StringUtils.isBlank(s) ) {

                CommentStartsWith cs = new CommentStartsWith(s);

                builder.skipComments(cs);

            }

            builder.surroundingSpacesNeedQuotes(CSVStoreParameters

                    .getSurroundingSpacesNeedQuotes(params));

            QuoteMode quoteMode = CSVStoreParameters.getQuoteMode(params);

            if ( quoteMode != null ) {

                builder.useQuoteMode(quoteMode);

            }

            return builder.build();

        } catch (Exception e) {

            logger.warn("Can't make preferences for CSV '" + getFullFileName()

                    + "'.", e);

            return null;

        }

    }

    private String getFullFileName() {

        // Usar solo para mostrar mensajes en el logger.

        String s;

        try {

            s = getParameters().getFile().getAbsolutePath();

        } catch (Exception e2) {

            s = "(unknow)";

        }

        return s;        

    }

    @Override

    public int getLine() {

        if( this.reader==null ) {

            return 0;

        }

        return this.reader.getLineNumber();

    }

    @Override

    public List<String> nextRowValues() {

        try {

            return this.read();

        } catch (IOException ex) {

            throw new RuntimeException(ex);

        }

    }

}