JAVA poi导出为excel详细范例

import java.io.IOException;
import java.io.OutputStream;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;

import org.apache.commons.io.IOUtils;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.ss.usermodel.CellStyle;
import org.apache.poi.ss.usermodel.DataFormat;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.util.CellRangeAddress;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

public final class ExcelWriter {
    public static final class Cell {
        private Workbook wb;
        private org.apache.poi.ss.usermodel.Cell target;

        private Cell(Workbook wb, org.apache.poi.ss.usermodel.Cell cell) {
            this.wb = wb;
            this.target = cell;
        }
        public void setCellValue(String value) {
            this.target.setCellValue(value);
        }
        public void setCellValue(Date value) {
            if (null == value) {
                this.setCellValue("未设置");
                return;
            }
            CellStyle style = this.wb.createCellStyle();
            DataFormat format = wb.createDataFormat();
            style.setDataFormat(format.getFormat("yyyy/m/d hh:mm:ss"));
            this.target.setCellStyle(style);
            this.target.setCellValue(value);
        }
        public void setCellValue(double value) {
            CellStyle style = this.wb.createCellStyle();
            DataFormat format = wb.createDataFormat();
            style.setDataFormat(format.getFormat("###,##0"));
            this.target.setCellStyle(style);
            this.target.setCellValue(value);
        }

        public void setCellStyle(CellStyle style){
            this.target.setCellStyle(style);
        }
    }

    public static final class Sheet{
        private Workbook wb;
        private org.apache.poi.ss.usermodel.Sheet sheet;
        private Sheet(Workbook wb, org.apache.poi.ss.usermodel.Sheet sheet) {
            this.sheet = sheet;
            this.wb = wb;
        }

        public Cell getOrCreateCell(int rowBasedZero, int cellBasedZero) {
            Row row = this.sheet.getRow(rowBasedZero);
            if (null == row) {
                row = this.sheet.createRow(rowBasedZero);
            }
            return new Cell(this.wb, row.getCell(cellBasedZero, Row.CREATE_NULL_AS_BLANK));
        }

        //合并单元格
        public void mergedRegion(int intFirstRow, int intLastRow, int intFirstColumn, int intLastColumn){
            this.sheet.addMergedRegion(new CellRangeAddress(intFirstRow, intLastRow, intFirstColumn, intLastColumn));
        }

        //添加居中的样式
        public CellStyle addStyle(){
            CellStyle style = wb.createCellStyle();
            style.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);// 垂直
            style.setAlignment(HSSFCellStyle.ALIGN_CENTER);// 水平
            return style;
        }

    }
    private Map<String, Sheet> sheetMap = new HashMap<String, Sheet>();
    private OutputStream out;
    private Workbook wb;

    public ExcelWriter(OutputStream out) {
        this.out = out;
        wb = new XSSFWorkbook();
    }

    public Sheet getOrCreateSheet(String sheet) {
        Sheet sheet1 = this.sheetMap.get(sheet);
        if (null != sheet1) {
            return sheet1;
        }
        org.apache.poi.ss.usermodel.Sheet xlsSheet = this.wb.getSheet(sheet);
        if (null == xlsSheet) {
            xlsSheet = this.wb.createSheet(sheet);
        }
        Sheet obj = new Sheet(this.wb, xlsSheet);
        this.sheetMap.put(sheet, obj);
        return obj;
    }

    public void write() throws IOException {
        this.wb.write(this.out);
    }

    public void close() {
        this.sheetMap.clear();
        IOUtils.closeQuietl

补充：软件开发 , Java ,