java Excel导出

Posted 2020-11-06 vixviy

Excel 导出

@(JAVA)[导出excel]

• srv

/**
 * 
 * @param response 
 * @param list 需导出的数据
 */
void createExcelWorkBookInfo(HttpServletResponse response, List<RtHtsyPositionCoverPojo> list);

• srvImpl

@Override
    public void createExcelWorkBookInfo(HttpServletResponse response, List<RtHtsyPositionCoverPojo> list) {
        String nowStr = new Date().getTime() + "";
        OutputStream out = null;
        try {
            out = response.getOutputStream();
            response.reset();
            response.setHeader("content-disposition",
                    "attachment;filename=" + new String(("信息导出" + nowStr).getBytes("gb2312"), "ISO8859-1") + ".xls");
            response.setContentType("APPLICATION/msexcel");
            HSSFWorkbook workbook = new HSSFWorkbook();
            //需要导出的字段
            Map<String, String> fildsMap = new HashMap<>();
            fildsMap.put("declareYear", "申报年度");
            fildsMap.put("working","单位");
            fildsMap.put("name","姓名");
            fildsMap.put("udicTecOqCurVal","现任职资格");
            fildsMap.put("udicTecOqDecVal","申请任职资格");
            fildsMap.put("status","申报状态");
            excelService.export(list, fildsMap, workbook, null);
            workbook.write(out);
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                // 强行将响应缓存中的内容发送到目的地
                response.flushBuffer();
                if (out != null) {
                    out.flush();
                    out.close();
                }
            } catch (IOException e) {
                LOGGER.error(e.toString());
            }
        }
    }

• ExcelService

public interface ExcelService {
    <T> void export(List<T> results, Map<String, String> fildsMap, HSSFWorkbook wb, Integer rowNum);
}

• ExcelService

import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import org.apache.commons.lang3.ArrayUtils;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFFont;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.util.HSSFColor;
import org.springframework.stereotype.Service;
import com.wisdombud.casic4.web.commonexcel.service.ExcelService;
@Service
public class ExcelServiceImpl implements ExcelService{
    public <T> void export(List<T> results, Map<String, String> fildsMap, HSSFWorkbook wb, Integer rowNum) {
        if (rowNum == null) {
            rowNum = rowMaxNum;
        }
        for (int i = 0; i < results.size(); i += rowNum) {
            List<T> newlist = new ArrayList<>();
            if ((i + rowNum) < results.size()) {
                newlist = results.subList(i, i + rowNum);
            } else {
                newlist = results.subList(i, results.size());
            }
            HSSFSheet sheet = wb.createSheet();
            for (int j = 0; j < fildsMap.size(); j++) {
                sheet.setColumnWidth(i, 5000);
            }
            this.fillCommonHeader(wb, sheet, fildsMap);
            this.fillCommonBody(newlist, sheet, wb, fildsMap);
        }
    }
    
    private void fillCommonHeader(HSSFWorkbook wb, HSSFSheet sheet, Map<String, String> fildsMap) {
        HSSFCellStyle style = wb.createCellStyle();
        style.setAlignment(HSSFCellStyle.ALIGN_CENTER);
        HSSFFont font = wb.createFont();
        font.setColor(HSSFColor.BLACK.index);
        font.setFontHeightInPoints((short) 18);
        style.setFont(font);
        HSSFRow row = sheet.createRow(0);
        int i = 0;
        for (String key : fildsMap.keySet()) {
            HSSFCell cell = row.createCell(i++);
            String value = fildsMap.get(key);
            cell.setCellValue(value);
            cell.setCellStyle(style);
        }
    }
    
    private <T> void fillCommonBody(List<T> results, HSSFSheet sheet, HSSFWorkbook wb, Map<String, String> fildsMap) {
        HSSFCellStyle style = wb.createCellStyle();
        style.setAlignment(HSSFCellStyle.ALIGN_CENTER);
        HSSFFont font = wb.createFont();
        font.setColor(HSSFColor.BLACK.index);
        font.setFontHeightInPoints((short) 16);
        style.setFont(font);
        int i = 1;
        for (T inst : results) {
            HSSFRow row = sheet.createRow(i++);
            row.setRowStyle(style);
            int j = 0;
            for (String key : fildsMap.keySet()) {
                HSSFCell cell = row.createCell(j++);
                String val = setCell(key, inst);
                cell.setCellValue(val);
            }
        }
    }
    

    @SuppressWarnings("rawtypes")
    private <T> String setCell(String field, T data) {
        String val = "";

        Class clazz = data.getClass();
        Field[] fields = ArrayUtils.addAll(clazz.getDeclaredFields(), clazz.getSuperclass().getDeclaredFields());
        for (int i = 0; i < fields.length; i++) {
            if (fields[i].getName().equals(field)) {
                try {
                    Object resultObject = invokeMethod(data, fields[i].getName(), null);
                    if (resultObject == null) {
                        resultObject = "";
                    }
                    val = resultObject.toString();
                    break;
                } catch (SecurityException | NoSuchMethodException | IllegalArgumentException | IllegalAccessException
                        | InvocationTargetException e) {
                    e.printStackTrace();
                }
            }
        }

        return val;
    }
    
    
    public Object invokeMethod(Object owner, String fieldname, Object[] args) throws SecurityException,
            NoSuchMethodException, IllegalArgumentException, IllegalAccessException, InvocationTargetException {
        Class ownerClass = owner.getClass();
        
        Method method = null;
        method = ownerClass.getMethod(this.toGetter(fieldname));
        
        Object object = null;
        object = method.invoke(owner);
        
        return object;
        }
    
    public String toGetter(String fieldname) {

        if (fieldname == null || fieldname.length() == 0) {
            return null;
        }

        if (fieldname.length() > 2) {
            String second = fieldname.substring(1, 2);
            if (second.equals(second.toUpperCase())) {
                return new StringBuffer("get").append(fieldname).toString();
            }
        }

        fieldname = new StringBuffer("get").append(fieldname.substring(0, 1).toUpperCase())
                .append(fieldname.substring(1)).toString();

        return fieldname;
    }

    
}

• maven

<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi</artifactId>
    <version>3.9</version>
</dependency>
<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi-ooxml</artifactId>
    <version>3.9</version>
</dependency>
<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi-scratchpad</artifactId>
    <version>3.9</version>
</dependency>