com.tecacet.jflat.excel.PoiExcelReader.java Source code

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Here is the source code for com.tecacet.jflat.excel.PoiExcelReader.java

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/*
 Copyright 2008 TecAceT Ltd.
    
 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 com.tecacet.jflat.excel;

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.text.DecimalFormat;
import java.text.NumberFormat;
import java.util.ArrayList;
import java.util.List;

import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.DateUtil;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.usermodel.WorkbookFactory;

import com.tecacet.jflat.DefaultRowMapper;
import com.tecacet.jflat.FlatFileReaderCallback;
import com.tecacet.jflat.ReaderRowMapper;

public class PoiExcelReader<T> extends ExcelReader<T> {

    protected Workbook workbook = null;
    protected Sheet currentSheet = null;

    private final InputStream is;

    private NumberFormat numberFormat = new DecimalFormat("#.#####");

    @SuppressWarnings("unchecked")
    public PoiExcelReader(String filename) throws IOException, InvalidFormatException {
        this(filename, new DefaultRowMapper());
    }

    public PoiExcelReader(String filename, ReaderRowMapper<T> mapper) throws IOException {
        is = new FileInputStream(filename);
        Workbook wb;
        try {
            wb = WorkbookFactory.create(is);
        } catch (InvalidFormatException e) {
            throw new IOException(e);
        }
        currentSheet = wb.getSheetAt(0);
        this.rowMapper = mapper;
        this.skipLines = DEFAULT_SKIP_LINES;
    }

    /**
     * Navigate the flat file and invoke the callback for each row.
     * 
     * @param callback
     * @throws IOException
     */
    public void readWithCallback(FlatFileReaderCallback<T> callback) {
        readSheet(currentSheet, callback);
    }

    protected void readSheet(Sheet sheet, FlatFileReaderCallback<T> callback) {
        for (int rowIndex = sheet.getFirstRowNum(); rowIndex <= sheet.getLastRowNum(); rowIndex++) {
            Row row = sheet.getRow(rowIndex);
            if (rowIndex < skipLines + sheet.getFirstRowNum()) {
                continue;
            }
            String[] tokens = readRow(row);
            T bean = rowMapper.getRow(tokens, rowIndex + 1);
            callback.processRow(rowIndex, tokens, bean);
        }
    }

    protected String[] readRow(Row row) {
        List<String> tokens = new ArrayList<String>();
        for (int c = row.getFirstCellNum(); c < row.getLastCellNum(); c++) {
            Cell cell = row.getCell(c);
            String cellValue = "";
            if (cell != null) {
                cellValue = getCellContentAsString(cell);
            }
            tokens.add(cellValue);
        }
        return tokens.toArray(new String[tokens.size()]);
    }

    /**
     * Clean up resources
     * 
     * @throws IOException
     */
    public void close() throws IOException {
        is.close();
    }

    //TODO toString conversions should respect registered converters
    private String getCellContentAsString(Cell cell) {
        switch (cell.getCellType()) {
        case Cell.CELL_TYPE_STRING:
            return cell.getRichStringCellValue().getString();
        case Cell.CELL_TYPE_NUMERIC:
            if (DateUtil.isCellDateFormatted(cell)) {
                return cell.getDateCellValue().toString();
            } else {
                double d = cell.getNumericCellValue();
                // TODO find a flexible enough format for all numeric types
                return numberFormat.format(d);
                // return Double.toString(d);
            }
        case Cell.CELL_TYPE_BOOLEAN:
            boolean b = cell.getBooleanCellValue();
            return Boolean.toString(b);
        case Cell.CELL_TYPE_FORMULA:
            return cell.getCellFormula();
        case Cell.CELL_TYPE_BLANK:
            return "";
        case Cell.CELL_TYPE_ERROR:
            byte bt = cell.getErrorCellValue();
            return Byte.toString(bt);
        default:
            return cell.getStringCellValue();

        }
    }

}