package methods;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.CellStyle;
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.xssf.usermodel.XSSFWorkbook;
public class ExcelParse {
public <T> void WriteExcel(List<T> list) throws NoSuchMethodException, SecurityException, IllegalAccessException,
IllegalArgumentException, InvocationTargetException, ParseException {
XSSFWorkbook workbook = new XSSFWorkbook();
Sheet sheet = workbook.createSheet(list.get(0).getClass().getName());
Field[] fields = null;
for (int i = 0; i < list.size(); i++) {
fields = list.get(i).getClass().getDeclaredFields();
System.out.println(list.get(i));
if (i == 0) {
Row row = sheet.createRow(i);
for (int j = 0; j < fields.length; j++) {
Cell cell = row.createCell(j);
cell.setCellValue(fields[j].getName());
System.out.println(fields[j].getName().toString());
}
}
Row row = sheet.createRow(i + 1);
for (int j = 0; j < fields.length; j++) {
/*截取方法名的第一個字符變大寫*/
String firstLetter = fields[j].getName().substring(0, 1).toUpperCase();
/*拼接get方法名*/
String getter = "get" + firstLetter + fields[j].getName().substring(1);
/*變成get方法*/
Method method = list.get(i).getClass().getMethod(getter, new Class[] {});
/*獲取value值*/
Object value = method.invoke(list.get(i), new Object[]{});
System.out.println(fields[j].getType().toString());
Cell cell=row.createCell(j);
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
CellStyle dateCellStyle=workbook.createCellStyle();
short df=workbook.createDataFormat().getFormat("yyyy-mm-dd");
dateCellStyle.setDataFormat(df);
switch(fields[j].getType().toString()){
case "int":
case "short":
case "long":
case "double":
cell.setCellType(Cell.CELL_TYPE_NUMERIC);
cell.setCellValue(Double.parseDouble(value.toString()));break;
case "class java.util.Date":
String temp = sdf.format((Date)value);
Date date=sdf.parse(temp);
cell.setCellType(Cell.CELL_TYPE_NUMERIC);
cell.setCellValue(date);
cell.setCellStyle(dateCellStyle);break;
case "class java.util.Calendar":row.createCell(j).setCellValue((Calendar)value);break;
default:row.createCell(j).setCellValue(value.toString());break;
}
}
}
try {
FileOutputStream fileOut = new FileOutputStream("D:/Result.xlsx");
//BufferedOutputStream bos = new BufferedOutputStream(fileOut);
workbook.write(fileOut);
fileOut.close();
//JOptionPane.showMessageDialog(null, "導出成功");
} catch (FileNotFoundException e) {
//JOptionPane.showMessageDialog(null, "導出失敗");
e.printStackTrace();
} catch (IOException e) {
//JOptionPane.showMessageDialog(null, "導出失敗");
e.printStackTrace();
}
}
/*解析excel 參數是文件地址返回值是：list*/public List<Map<String, String>> ReadExcel(String filepath) {
List<Map<String, String>> sheetData = new ArrayList<Map<String, String>>();
Workbook workbook = checkFile(filepath);
Sheet sheet = workbook.getSheetAt(0);
Map<Integer, String> rowMenu = setRowMap(sheet);
for(int rowNum = 1;rowNum<=sheet.getLastRowNum();rowNum++){
Row row = sheet.getRow(rowNum);
Map<String, String> rowData = getRowData(row, rowMenu);
sheetData.add(rowData);
}
return sheetData;
}
/*判斷是什麼文件*/
private Workbook checkFile(String filePath){
FileInputStream inStream=null;
try {
inStream = new FileInputStream(new File(filePath));
} catch (FileNotFoundException e) {
e.printStackTrace();
}
if(filePath.matches("^.+.xls$")){
try {
System.out.println("this is xls");
return new HSSFWorkbook(inStream);
} catch (IOException e) {
e.printStackTrace();
}
}
if(filePath.matches("^.+.xlsx$")){
try {
System.out.println("this id xlsx");
return new XSSFWorkbook(inStream);
} catch (IOException e) {
e.printStackTrace();
}
}else{
try {
throw new FileNotFoundException("文件不對");
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
return null;
}
private Map<Integer, String> setRowMap(Sheet sheet) {
Map<Integer, String> rowMenu = new HashMap<Integer, String>();
Row row = sheet.getRow(0);
for(int colNum = 0;colNum<row.getLastCellNum();colNum++){
String menuValue = row.getCell(colNum).getStringCellValue();
rowMenu.put(colNum, menuValue);
}
return rowMenu;
}
private Map<String,String> getRowData(Row row,Map<Integer,String> rowMenu){
Map<String,String> rowData=new HashMap<String,String>();
for(int colNum=0;colNum<row.getLastCellNum();colNum++){
Cell cell=row.getCell(colNum);
String cellValue=null;
switch (cell.getCellType()) {
//數值類型
case Cell.CELL_TYPE_NUMERIC:
//進一步判斷 ，單元格格式是日期格式
if (DateUtil.isCellDateFormatted(cell)) {
SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");
cellValue = sdf.format(cell.getDateCellValue());
}
else{
//數值
double value = cell.getNumericCellValue();
int intValue = (int) value;
cellValue = value - intValue == 0 ? String.valueOf(intValue) : String.valueOf(value);}break;
case Cell.CELL_TYPE_STRING:cellValue = cell.getStringCellValue();break;
case Cell.CELL_TYPE_BOOLEAN:cellValue = String.valueOf(cell.getBooleanCellValue());break;
//判斷單元格是公式格式，需要做一種特殊處理來得到相應的值
case Cell.CELL_TYPE_FORMULA:{
try{
cellValue = String.valueOf(cell.getNumericCellValue());
}
catch(IllegalStateException e){
cellValue = String.valueOf(cell.getRichStringCellValue());
}
}break;
case Cell.CELL_TYPE_BLANK:cellValue = "";break;
case Cell.CELL_TYPE_ERROR:cellValue = "";break;
default:cellValue=cell.toString().trim();break;
}
rowData.put(rowMenu.get(colNum), cellValue);
}
return rowData;
}
}text測試程序
將excel中的數據導出到控制面板
數據輸入表中的結果：
