Java POI组件——读、筛选、写Excel
接上一篇《Java POI组件——写Excel》http://blog.csdn.net/chy555chy/article/details/52739711
假设有这么一个需求——领导挑出了一些员工的名字（准备评先进），只需要这些员工的部分信息。需要你从员工表中找出它们和这些员工相应的某些信息。
员工表如下
评先进的人是：”陈七”, “张三”, “林八”, “钱二”, “东方不败”
- 需要的字段要按如下顺序排序：”姓名”,”员工号”,”部门”,”年龄”,”入岗时间”
- 另外需要在首列生成索引，自动排序
结果如下
则本次读写Excel需要使用到的jar为
poi-3.15.jar
poi-ooxml-3.15.jar
poi-ooxml-schemas-3.15.jar
commons-collections4-4.1.jar
xmlbeans-2.6.0.jar
package com.example.pkg;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.text.Format;
import java.util.ArrayList;
import java.util.Date;
import org.apache.poi.EncryptedDocumentException;
import org.apache.poi.hssf.extractor.ExcelExtractor;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
import org.apache.poi.ss.usermodel.BorderStyle;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.CellStyle;
import org.apache.poi.ss.usermodel.CellType;
import org.apache.poi.ss.usermodel.CellValue;
import org.apache.poi.ss.usermodel.CreationHelper;
import org.apache.poi.ss.usermodel.DataFormat;
import org.apache.poi.ss.usermodel.DataFormatter;
import org.apache.poi.ss.usermodel.DateUtil;
import org.apache.poi.ss.usermodel.FillPatternType;
import org.apache.poi.ss.usermodel.Font;
import org.apache.poi.ss.usermodel.FormulaEvaluator;
import org.apache.poi.ss.usermodel.IndexedColors;
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.usermodel.WorkbookFactory;
import org.apache.poi.ss.util.CellRangeAddress;
import org.apache.poi.xssf.extractor.XSSFExcelExtractor;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
public class PoiExcelClass {
/**
* 筛选并重组表格(自动生成索引),只筛选第一个sheet
*
* @params originFileName 源文件名
* @params targetFileName 目标文件名
* @params columns 只提取原表格中出现过的列(不包括索引)
* @params filterItems 筛选条件,只提取出现该项的行
*/
private static void filter(String originFileName, String targetFileName, String[] columns, String filterColumn, String[] filterItems) {
InputStream inp = null;
Workbook workbook = null;
ArrayList columnIndexList = new ArrayList(columns.length);
int filterColumnIndex = -1;
Workbook workbook_w = null;
FileOutputStream fos = null;
try {
inp = new FileInputStream(originFileName);
workbook = WorkbookFactory.create(inp);
FormulaEvaluator evaluator = workbook.getCreationHelper().createFormulaEvaluator();
Sheet sheet = workbook.getSheetAt(0);
Row row = sheet.getRow(0);
// 如果未发现有行,则返回
if (row == null)
return;
// 第一行规定必须是标题
for (Cell cell : row) {
if (cell.getCellTypeEnum() == CellType.STRING) {
for (String str : columns) {
String value = cell.getStringCellValue();
if (str.equals(value)) {
int index = cell.getColumnIndex();
columnIndexList.add(index);
if(filterColumnIndex == -1 && filterColumn.equals(value)) {
filterColumnIndex = index;
}
break;
}
}
}
}
// 如果待筛选的字段一个也没找到就返回
if (columnIndexList.size() == 0 || filterColumnIndex == -1)
return;
if (targetFileName.endsWith(SUFFIX_XSSF)) {
workbook_w = new XSSFWorkbook();
} else {
workbook_w = new HSSFWorkbook();
}
Sheet sheet_w = workbook_w.createSheet("Sheet1");
int rowIndex = 1;
//添加标题行
Row row_w = sheet_w.createRow(0);
row_w.createCell(0).setCellValue("索引");
for (int i = 0; i < columnIndexList.size(); i++) {
String value = row.getCell(columnIndexList.get(i)).getStringCellValue();
row_w.createCell(i+1).setCellValue(value);
}
for (Row r : sheet) {
if(r.getRowNum() == 0) continue;
Cell cell = r.getCell(filterColumnIndex);
if(cell.getCellTypeEnum() == CellType.STRING) {
String value = cell.getStringCellValue();
for(String str : filterItems) {
if(str.equals(value)) {
//该行满足筛选条件
row_w = sheet_w.createRow(rowIndex);
row_w.createCell(0).setCellFormula("ROW()-1");
for (int i = 0; i < columnIndexList.size(); i++) {
int index = columnIndexList.get(i);
Cell c = r.getCell(index);
Cell c_w = row_w.createCell(i+1, c.getCellType());
//从原单元格中继承单元格格式,包括内容格式、边框、颜色、字体。注意:这里必须先create，不能直接设置其他单元格的格式
CellStyle cs = workbook_w.createCellStyle();
cs.cloneStyleFrom(c.getCellStyle());
c_w.setCellStyle(cs);
//以下是错误的方法,Error:This Style does not belong to the supplied Workbook Stlyes Source. Are you trying to assign a style from one workbook to the cell of a differnt workbook?
//c_w.setCellStyle(c.getCellStyle());
switch (c.getCellTypeEnum()) {
case _NONE:
break;
case BLANK:
break;
case BOOLEAN:
c_w.setCellValue(c.getBooleanCellValue());
break;
case ERROR:
c_w.setCellErrorValue(c.getErrorCellValue());
break;
case FORMULA:
//唯一的问题就是公式由于是根据单元格计算,新表可能相应的单元格存放不同的数据,造成计算结果不同
// c_w.setCellFormula(c.getCellFormula());
CellValue cellValue = evaluator.evaluate(c);
c_w.setCellType(cellValue.getCellType());
switch (cellValue.getCellTypeEnum()) {
case BOOLEAN:
c_w.setCellValue(cellValue.getBooleanValue());
break;
case ERROR:
c_w.setCellErrorValue(cellValue.getErrorValue());
break;
case NUMERIC:
if(DateUtil.isCellDateFormatted(c)) {
c_w.setCellValue(c.getDateCellValue());
} else {
c_w.setCellValue(c.getNumericCellValue());
}
break;
case STRING:
c_w.setCellValue(c.getRichStringCellValue());
break;
default:
break;
}
break;
case NUMERIC:
if(DateUtil.isCellDateFormatted(c)) {
c_w.setCellValue(c.getDateCellValue());
} else {
c_w.setCellValue(c.getNumericCellValue());
}
break;
case STRING:
c_w.setCellValue(c.getRichStringCellValue());
break;
}
}
rowIndex++;
break;
}
}
}
}
fos = new FileOutputStream(targetFileName);
workbook_w.write(fos);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (EncryptedDocumentException e) {
e.printStackTrace();
} catch (InvalidFormatException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (inp != null) {
try {
inp.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (workbook != null) {
try {
workbook.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (workbook_w != null) {
try {
workbook_w.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (fos != null) {
try {
fos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
public static void main(String[] args) {
filter(EXCEL_PATH, "filter.xlsx", new String[] {"姓名","员工号","部门","年龄","入岗时间"}, "姓名", new String[] {"陈七", "张三", "林八", "钱二", "东方不败"});
}
虽然能基本完成这个任务，但这里还有一个不完美的地方，那就是公式单元格。
这里公式单元格的处理方式为：计算出该值，然后将其值填入对应单元。
其实更好的做法应该是将公式中的字段进行映射，映射到新的字段中。