java相关工具类（excel导出）

package com.longrise.SWMS.Util;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

import org.apache.poi.hssf.usermodel.HSSFDataFormat;
import org.apache.poi.hssf.util.HSSFColor;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.CellStyle;
import org.apache.poi.ss.usermodel.Font;
import org.apache.poi.ss.usermodel.RichTextString;
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.util.CellRangeAddress;
import org.apache.poi.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFCellStyle;
import org.apache.poi.xssf.usermodel.XSSFFont;
import org.apache.poi.xssf.usermodel.XSSFRichTextString;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

/**
 * Excel 相关操作类(小数据量写入<=60000)
 */
public class ExcelUtils {

      //设置单元格默认表宽
    private static final int DEFAULT_COLUMN_SIZE = 20;


    /**
     * 断言Excel文件写入之前的条件
     *
     * @param directory 目录
     * @param fileName  文件名
     * @return file
     * @throws IOException
     */
    private static File assertFile(String directory, String fileName) throws IOException {
        File tmpFile = new File(directory + File.separator + fileName + ".xlsx");
        if (tmpFile.exists()) {
            if (tmpFile.isDirectory()) {
                throw new IOException("File '" + tmpFile + "' exists but is a directory");
            }
            if (!tmpFile.canWrite()) {
                throw new IOException("File '" + tmpFile + "' cannot be written to");
            }
        } else {
            File parent = tmpFile.getParentFile();
            if (parent != null) {
                if (!parent.mkdirs() && !parent.isDirectory()) {
                    throw new IOException("Directory '" + parent + "' could not be created");
                }
            }
        }
        return tmpFile;
    }


    /**
     * 日期转化为字符串,格式为yyyy-MM-dd HH:mm:ss
     */
    private static String getCnDate(Date date) {
        String format = "yyyy-MM-dd HH:mm:ss";
        SimpleDateFormat sdf = new SimpleDateFormat(format);
        return sdf.format(date);
    }


    /**
     * Excel 导出，POI实现
     *
     * @param fileName    文件名
     * @param sheetName   sheet页名称
     * @param columnNames 表头列表名
     * @param sheetTitle  sheet页Title
     * @param titleInfo  打印信息
     * @param objects     目标数据集
     */
    public static File writeExcel(String directory, String fileName, String sheetName, List < String > columnNames,List<String> titleInfo,
        String sheetTitle, List < List < Object >> objects, boolean append) throws IOException {
        File tmpFile = assertFile(directory, fileName);
        return exportExcel(tmpFile, sheetName, columnNames,titleInfo, sheetTitle, objects, append);
    }


    /**
     * Excel 导出，POI实现，先写入Excel标题，与writeExcelData配合使用
     * 先使用writeExcelTitle再使用writeExcelData
     *
     * @param directory   目录
     * @param fileName    文件名
     * @param sheetName   sheetName
     * @param columnNames 列名集合
     * @param sheetTitle  表格标题
     * @param append      是否在现有的文件追加
     * @return file
     * @throws ReportInternalException
     * @throws IOException
     */
    public static File writeExcelTitle(String directory, String fileName, String sheetName, List < String > columnNames,
        String sheetTitle, boolean append) throws IOException {
        File tmpFile = assertFile(directory, fileName);
        return exportExcelTitle(tmpFile, sheetName, columnNames, sheetTitle, append);
    }


    /**
     * Excel 导出，POI实现，写入Excel数据行列，与writeExcelTitle配合使用
     * 先使用writeExcelTitle再使用writeExcelData
     *
     * @param directory 目录
     * @param fileName  文件名
     * @param sheetName sheetName
     * @param objects   数据信息
     * @return file
     * @throws ReportInternalException
     * @throws IOException
     */
    public static File writeExcelData(String directory, String fileName, String sheetName, List < List < Object >>
        objects)
    throws IOException {
        File tmpFile = assertFile(directory, fileName);
        return exportExcelData(tmpFile, sheetName, objects);
    }


    /**
     * 导出字符串数据
     *
     * @param file        文件名
     * @param columnNames 表头
     * @param sheetTitle  sheet页Title
     * @param append      是否追加写文件
     * @return file
     * @throws ReportInternalException
     */
    private static File exportExcelTitle(File file, String sheetName, List < String > columnNames,
        String sheetTitle, boolean append) throws IOException {
        // 声明一个工作薄
        Workbook workBook;
        if (file.exists() && append) {
            workBook = new XSSFWorkbook(new FileInputStream(file));
        } else {
            workBook = new XSSFWorkbook();
        }
        Map < String, CellStyle > cellStyleMap = styleMap(workBook);
        // 表头样式
        CellStyle headStyle = cellStyleMap.get("head");
        // 生成一个表格
        Sheet sheet = workBook.getSheet(sheetName);
        if (sheet == null) {
            sheet = workBook.createSheet(sheetName);
        }
        //最新Excel列索引,从0开始
        int lastRowIndex = sheet.getLastRowNum();
        if (lastRowIndex > 0) {
            lastRowIndex++;
        }
        // 设置表格默认列宽度
        //sheet.setDefaultColumnWidth(DEFAULT_COLUMN_SIZE);
        // 合并单元格
        sheet.addMergedRegion(new CellRangeAddress(lastRowIndex, lastRowIndex, 0, columnNames.size() - 1));
        // 产生表格标题行
        Row rowMerged = sheet.createRow(lastRowIndex);
        lastRowIndex++;
        Cell mergedCell = rowMerged.createCell(0);
        mergedCell.setCellStyle(headStyle);
        mergedCell.setCellValue(new XSSFRichTextString(sheetTitle));
        // 产生表格表头列标题行
        Row row = sheet.createRow(lastRowIndex);
        for (int i = 0; i < columnNames.size(); i++) {
            
            Cell cell = row.createCell(i);
            cell.setCellStyle(headStyle);
            RichTextString text = new XSSFRichTextString(columnNames.get(i));
            cell.setCellValue(text);
        }
        try {
            OutputStream ops = new FileOutputStream(file);
            workBook.write(ops);
            ops.flush();
            ops.close();
        } catch (IOException e) {
            System.err.println(e);
        }
        return file;
    }


    /**
     * 导出字符串数据
     *
     * @param file    文件名
     * @param objects 目标数据
     * @return
     * @throws ReportInternalException
     */
    private static File exportExcelData(File file, String sheetName, List < List < Object >> objects) throws IOException {
        // 声明一个工作薄
        Workbook workBook;
        if (file.exists()) {
            workBook = new XSSFWorkbook(new FileInputStream(file));
        } else {
            workBook = new XSSFWorkbook();
        }


        Map < String, CellStyle > cellStyleMap = styleMap(workBook);
        // 正文样式
        CellStyle contentStyle = cellStyleMap.get("content");
        //正文整数样式
        CellStyle contentIntegerStyle = cellStyleMap.get("integer");
        //正文带小数整数样式
        CellStyle contentDoubleStyle = cellStyleMap.get("double");
        // 生成一个表格
        Sheet sheet = workBook.getSheet(sheetName);
        if (sheet == null) {
            sheet = workBook.createSheet(sheetName);
        }
        //最新Excel列索引,从0开始
        int lastRowIndex = sheet.getLastRowNum();
        if (lastRowIndex > 0) {
            lastRowIndex++;
        }
        // 设置表格默认列宽度
        //sheet.setDefaultColumnWidth(DEFAULT_COLUMN_SIZE);
        
        // 遍历集合数据,产生数据行,前两行为标题行与表头行
        for (List < Object > dataRow: objects) {
            Row row = sheet.createRow(lastRowIndex);
            lastRowIndex++;
            for (int j = 0; j < dataRow.size(); j++) {
                Cell contentCell = row.createCell(j);
                Object dataObject = dataRow.get(j);
                
                if (dataObject != null) {
                    sheet.autoSizeColumn(j, true);
                    sheet.setColumnWidth(j,dataObject.toString().length()*2*256);
                    if (dataObject instanceof Integer) {
                        contentCell.setCellStyle(contentIntegerStyle);
                        contentCell.setCellValue(Integer.parseInt(dataObject.toString()));
                    } else if (dataObject instanceof Double) {
                        contentCell.setCellStyle(contentDoubleStyle);
                        contentCell.setCellValue(Double.parseDouble(dataObject.toString()));
                    } else if (dataObject instanceof Long && dataObject.toString().length() == 13) {
                        contentCell.setCellStyle(contentStyle);
                        contentCell.setCellValue(getCnDate(new Date(Long.parseLong(dataObject.toString()))));
                    } else if (dataObject instanceof Date) {
                        contentCell.setCellStyle(contentStyle);
                        contentCell.setCellValue(getCnDate((Date) dataObject));
                    } else {
                        contentCell.setCellStyle(contentStyle);
                        contentCell.setCellValue(dataObject.toString());
                    }
                } else {
                    contentCell.setCellStyle(contentStyle);
                    // 设置单元格内容为字符型
                    contentCell.setCellValue("");
                }
            }
        }
        try {
            OutputStream ops = new FileOutputStream(file);
            workBook.write(ops);
            ops.flush();
            ops.close();
        } catch (IOException e) {
            System.err.println(e);
        }
        return file;
    }


    /**
     * 导出字符串数据
     *
     * @param file        文件名
     * @param columnNames 表头
     * @param sheetTitle  sheet页Title
     * @param objects     目标数据
     * @param append      是否追加写文件
     * @return
     * @throws ReportInternalException
     */
    private static File exportExcel(File file, String sheetName, List < String > columnNames,List <String > titleInfo,
        String sheetTitle, List < List < Object >> objects, boolean append) throws IOException {
        // 声明一个工作薄
        Workbook workBook;
        if (file.exists() && append) {
            // 声明一个工作薄
            workBook = new XSSFWorkbook(new FileInputStream(file));
        } else {
            workBook = new XSSFWorkbook();
        }
        Map < String, CellStyle > cellStyleMap = styleMap(workBook);
        // 表头样式
        CellStyle headStyle = cellStyleMap.get("head");
        // 正文样式
        CellStyle contentStyle = cellStyleMap.get("content");
        //标题样式
        CellStyle titleStyle = cellStyleMap.get("title");
       //正文整数样式
        CellStyle contentIntegerStyle = cellStyleMap.get("integer");
        //正文带小数整数样式
        CellStyle contentDoubleStyle = cellStyleMap.get("double");
        // 生成一个表格
        Sheet sheet = workBook.getSheet(sheetName);
        if (sheet == null) {
            sheet = workBook.createSheet(sheetName);
        }
        //最新Excel列索引,从0开始
        int lastRowIndex = sheet.getLastRowNum();
        if (lastRowIndex > 0) {
            lastRowIndex++;
        }
        // 设置表格默认列宽度
        sheet.setDefaultColumnWidth(DEFAULT_COLUMN_SIZE);
        // 合并单元格
        sheet.addMergedRegion(new CellRangeAddress(lastRowIndex, lastRowIndex, 0, columnNames.size() - 1));
        // 产生表格标题行
        Row rowMerged = sheet.createRow(lastRowIndex);
        lastRowIndex++;
        Cell mergedCell = rowMerged.createCell(0);
        mergedCell.setCellStyle(headStyle);
        mergedCell.setCellValue(new XSSFRichTextString(sheetTitle));
        //产生打印信息行，并合并两个单元格
        sheet.addMergedRegion(new CellRangeAddress(lastRowIndex, lastRowIndex, 1,2));
        sheet.addMergedRegion(new CellRangeAddress(lastRowIndex, lastRowIndex, 4,5));
        sheet.addMergedRegion(new CellRangeAddress(lastRowIndex, lastRowIndex, 6,columnNames.size() - 1));
        Row rowInfo = sheet.createRow(lastRowIndex);
        lastRowIndex++;
        for (int i = 0; i < titleInfo.size(); i++) {
            Cell cell = rowInfo.createCell(i);
            cell.setCellStyle(contentStyle);
            RichTextString text = new XSSFRichTextString(titleInfo.get(i));
            cell.setCellValue(text);
        }
        
        // 产生表格表头列标题行
        Row row = sheet.createRow(lastRowIndex);
        lastRowIndex++;
        for (int i = 0; i < columnNames.size(); i++) {
            Cell cell = row.createCell(i);
            cell.setCellStyle(titleStyle);
            RichTextString text = new XSSFRichTextString(columnNames.get(i));
            cell.setCellValue(text);
        }
       
        // 遍历集合数据,产生数据行,前两行为标题行与表头行
        for (List < Object > dataRow: objects) {
            row = sheet.createRow(lastRowIndex);
            lastRowIndex++;
            for (int j = 0; j < dataRow.size(); j++) {
                Cell contentCell = row.createCell(j);
                Object dataObject = dataRow.get(j);
                if (dataObject != null) {
                    //sheet.autoSizeColumn(j, true);
                    //sheet.setColumnWidth(j,maxLongth*3*256);
                    if (dataObject instanceof Integer) {
                        contentCell.setCellType(XSSFCell.CELL_TYPE_NUMERIC);
                        contentCell.setCellStyle(contentIntegerStyle);
                        contentCell.setCellValue(Integer.parseInt(dataObject.toString()));
                    } else if (dataObject instanceof Double) {
                        contentCell.setCellType(XSSFCell.CELL_TYPE_NUMERIC);
                        contentCell.setCellStyle(contentDoubleStyle);
                        contentCell.setCellValue(Double.parseDouble(dataObject.toString()));
                    } else if (dataObject instanceof Long && dataObject.toString().length() == 13) {
                        contentCell.setCellType(XSSFCell.CELL_TYPE_STRING);
                        contentCell.setCellStyle(contentStyle);
                        contentCell.setCellValue(getCnDate(new Date(Long.parseLong(dataObject.toString()))));
                    } else if (dataObject instanceof Date) {
                        contentCell.setCellType(XSSFCell.CELL_TYPE_STRING);
                        contentCell.setCellStyle(contentStyle);
                        contentCell.setCellValue(getCnDate((Date) dataObject));
                    } else {
                        contentCell.setCellType(XSSFCell.CELL_TYPE_STRING);
                        contentCell.setCellStyle(contentStyle);
                        contentCell.setCellValue(dataObject.toString());
                    }
                } else {
                    contentCell.setCellStyle(contentStyle);
                    // 设置单元格内容为字符型
                    contentCell.setCellValue("");
                }
            }
        }
        try {
            OutputStream ops = new FileOutputStream(file);
            workBook.write(ops);
            ops.flush();
            ops.close();
        } catch (IOException e) {
            System.err.println(e);
        }
        return file;
    }


    /**
     * 创建单元格表头样式
     *
     * @param workbook 工作薄
     */
    private static CellStyle createCellHeadStyle(Workbook workbook) {
        CellStyle style = workbook.createCellStyle();
        // 设置边框样式
        style.setBorderBottom(XSSFCellStyle.BORDER_THIN);
        style.setBorderLeft(XSSFCellStyle.BORDER_THIN);
        style.setBorderRight(XSSFCellStyle.BORDER_THIN);
        style.setBorderTop(XSSFCellStyle.BORDER_THIN);
        //设置对齐样式
        style.setAlignment(XSSFCellStyle.ALIGN_CENTER);
        // 生成字体
        Font font = workbook.createFont();
        // 表头样式
        style.setFillPattern(XSSFCellStyle.SOLID_FOREGROUND);
        font.setFontHeightInPoints((short) 16);
        font.setBoldweight(XSSFFont.BOLDWEIGHT_BOLD);
        // 把字体应用到当前的样式
        style.setFont(font);
        return style;
    }
    
    /**
     * 创建单元格标题样式
     * @param workbook
     * @return
     */
    private static CellStyle createCellTitleStyle(Workbook workbook) {
        CellStyle style = workbook.createCellStyle();
        // 设置边框样式
        style.setBorderBottom(XSSFCellStyle.BORDER_THIN);
        style.setBorderLeft(XSSFCellStyle.BORDER_THIN);
        style.setBorderRight(XSSFCellStyle.BORDER_THIN);
        style.setBorderTop(XSSFCellStyle.BORDER_THIN);
        //设置对齐样式
        style.setAlignment(XSSFCellStyle.ALIGN_CENTER);
        // 生成字体
        Font font = workbook.createFont();
        // 表头样式
        style.setFillPattern(XSSFCellStyle.SOLID_FOREGROUND);
        style.setFillForegroundColor(HSSFColor.SKY_BLUE.index);
        font.setFontHeightInPoints((short) 12);
        font.setBoldweight(XSSFFont.BOLDWEIGHT_BOLD);
        // 把字体应用到当前的样式
        style.setFont(font);
        return style;
    }

    /**
     * 创建单元格正文样式
     *
     * @param workbook 工作薄
     */
    private static CellStyle createCellContentStyle(Workbook workbook) {
        CellStyle style = workbook.createCellStyle();
        // 设置边框样式
        style.setBorderBottom(XSSFCellStyle.BORDER_THIN);
        style.setBorderLeft(XSSFCellStyle.BORDER_THIN);
        style.setBorderRight(XSSFCellStyle.BORDER_THIN);
        style.setBorderTop(XSSFCellStyle.BORDER_THIN);
        //设置对齐样式
        style.setAlignment(XSSFCellStyle.ALIGN_CENTER);
        //自动换行
        style.setWrapText(true);
        // 生成字体
        Font font = workbook.createFont();
        // 正文样式
        style.setFillPattern(XSSFCellStyle.NO_FILL);
        style.setVerticalAlignment(XSSFCellStyle.VERTICAL_CENTER);
        font.setBoldweight(XSSFFont.BOLDWEIGHT_NORMAL);
        // 把字体应用到当前的样式
        style.setFont(font);
        return style;
    }


    /**
     * 单元格样式(Integer)列表
     */
    private static CellStyle createCellContent4IntegerStyle(Workbook workbook) {
        CellStyle style = workbook.createCellStyle();
        // 设置边框样式
        style.setBorderBottom(XSSFCellStyle.BORDER_THIN);
        style.setBorderLeft(XSSFCellStyle.BORDER_THIN);
        style.setBorderRight(XSSFCellStyle.BORDER_THIN);
        style.setBorderTop(XSSFCellStyle.BORDER_THIN);
        //设置对齐样式
        style.setAlignment(XSSFCellStyle.ALIGN_CENTER);
        // 生成字体
        Font font = workbook.createFont();
        // 正文样式
        style.setFillPattern(XSSFCellStyle.NO_FILL);
        style.setVerticalAlignment(XSSFCellStyle.VERTICAL_CENTER);
        font.setBoldweight(XSSFFont.BOLDWEIGHT_NORMAL);
        // 把字体应用到当前的样式
        style.setFont(font);
        style.setDataFormat(HSSFDataFormat.getBuiltinFormat("#,##0")); //数据格式只显示整数
        return style;
    }


    /**
     * 单元格样式(Double)列表
     */
    private static CellStyle createCellContent4DoubleStyle(Workbook workbook) {
        CellStyle style = workbook.createCellStyle();
        // 设置边框样式
        style.setBorderBottom(XSSFCellStyle.BORDER_THIN);
        style.setBorderLeft(XSSFCellStyle.BORDER_THIN);
        style.setBorderRight(XSSFCellStyle.BORDER_THIN);
        style.setBorderTop(XSSFCellStyle.BORDER_THIN);
        //设置对齐样式
        style.setAlignment(XSSFCellStyle.ALIGN_CENTER);
        // 生成字体
        Font font = workbook.createFont();
        // 正文样式
        style.setFillPattern(XSSFCellStyle.NO_FILL);
        style.setVerticalAlignment(XSSFCellStyle.VERTICAL_CENTER);
        font.setBoldweight(XSSFFont.BOLDWEIGHT_NORMAL);
        // 把字体应用到当前的样式
        style.setFont(font);
        style.setDataFormat(HSSFDataFormat.getBuiltinFormat("#,##0.00")); //保留两位小数点
        return style;
    }


    /**
     * 单元格样式列表
     */
    private static Map < String, CellStyle > styleMap(Workbook workbook) {
        Map < String, CellStyle > styleMap = new LinkedHashMap <String, CellStyle > ();
        styleMap.put("head", createCellHeadStyle(workbook));
        styleMap.put("title", createCellTitleStyle(workbook));
        styleMap.put("content", createCellContentStyle(workbook));
        styleMap.put("integer", createCellContent4IntegerStyle(workbook));
        styleMap.put("double", createCellContent4DoubleStyle(workbook));
        return styleMap;
    }
}

package client;

import java.io.IOException;
import java.sql.Date;
import java.util.LinkedList;
import java.util.List;
import tools.ExcelUtils;

public class ExploreTest {
    public static void main(String[] args) throws IOException {
        String sheetName = "sheet名字";
        String sheetTitle = "标头";
        List < String > columnNames = new LinkedList < > ();
        columnNames.add("测试标头长度自适应测试标头长度自适应测试标头长度自适应");
        columnNames.add("单元格2");
        columnNames.add("单元格3");
        columnNames.add("单元格4");
        columnNames.add("单元格5");
        columnNames.add("单元格6");


        //写入标题--第二种方式
        ExcelUtils.writeExcelTitle("D:\\tset", "biaoming1", sheetName, columnNames, sheetTitle, false);


        List < List < Object >> objects = new LinkedList < > ();
        for (int i = 0; i < 5; i++) {
            List < Object > dataA = new LinkedList < > ();
            dataA.add("哈哈");
            dataA.add(new Date(1451036631012L));
            dataA.add(1451036631012L);
            dataA.add("测试标头长度自适应测试标头长度自适应测试标头长度自适应");
            dataA.add(i);
            dataA.add(1.323 + i);
            objects.add(dataA);
        }
        try {
            //写入数据--第二种方式
        	ExcelUtils.writeExcelData("D:\\tset", "biaoming1", sheetName, objects);
            //直接写入数据--第一种方式
        	ExcelUtils.writeExcel("D:\\tset", "biaoming2", sheetName, columnNames, sheetTitle, objects, false);
        	System.out.println("数据写入成功！");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

}