How to Read Data from DB and write into Excel sheet using Apache POI

Read Data from DB and write into Excel sheet using Apache POI

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method to read data from the "resource_rbac_status" table and write into the excel sheet using apache POI HSSF API
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public static HSSFWorkbook generateExcel(){
Connection dbconn = null;
HSSFWorkbook wb = null;
try{
dbconn = RmsDBUtil.getDBConnection(); /// get the connection
Statement stmt= dbconn.createStatement();;
ResultSet rs= stmt.executeQuery ("SELECT * FROM resource_rbac_status");
ResultSetMetaData rsmd = rs.getMetaData ();

int columnCount = rsmd.getColumnCount ();

wb = new HSSFWorkbook();

HSSFSheet sheet = wb.createSheet("Excel Sheet");

HSSFRow rowhead = sheet.createRow((short) 0);

for (int j = 1; j <= columnCount; ++j) {
rowhead.createCell((short) ((short) j-1)).setCellValue(rsmd.getColumnLabel(j));
}

int index = 1;
while (rs.next()) {

HSSFRow row = sheet.createRow((short) index);
for (int j = 1; j <= columnCount; ++j){

String a=rsmd.getColumnTypeName(j);

if (a.equals("INTEGER")){

row.createCell((short) ((short) j-1)).setCellValue(rs.getInt(j));
} else {

row.createCell((short) ((short) j-1)).setCellValue(rs.getString(j));
}

}

index++;
}

System.out.println("Data is saved in excel file.Please check the excel file ");

//close the connection and statement

}
catch (Exception e) {
System.out.println(e);
}
finally{
// close the connection
}

return wb;

}
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How to Read an Excel sheet using Apache POI HSSF

How to read an excel sheet using POI API(HSSF)

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method to read the excel sheet and prepares the list(of Holiday DTOs) using apache POI API
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public static List parseHolidayExcel(String xlsPath) {

List holidayList = new ArrayList();
FileInputStream fis = null;
POIFSFileSystem fileSystem = null;

try {
fis = new FileInputStream(xlsPath);
fileSystem = new POIFSFileSystem(fis);

HSSFWorkbook workBook = new HSSFWorkbook(fileSystem);
HSSFSheet sheet = workBook.getSheetAt(0);
Iterator rows = sheet.rowIterator();
HolidayListDTO dto = null;
while (rows.hasNext()) {
HSSFRow row = rows.next();

if (row.getRowNum() == 0)
continue;

// System.out.println("Row no:"+row.getRowNum());
dto = new HolidayListDTO();
dto.setSiteStatus(row.getCell((short) 0).getStringCellValue());
dto.setCountry(row.getCell((short) 1).getStringCellValue());
dto.setLocation(row.getCell((short) 2).getStringCellValue());
dto.setHoliday_date((Date) (row.getCell((short) 3)
.getDateCellValue()));
dto.setDay(row.getCell((short) 4).getStringCellValue());
dto.setOccasion(row.getCell((short) 5).getStringCellValue());

holidayList.add(dto);

}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
fis.close();
} catch (IOException e) {
e.printStackTrace();
}
}

return holidayList;
}


To read an Excel sheet using POI API(HSSF) : Data Holder to hold details about the holidays....

import java.io.Serializable;
import java.util.Date;

public class HolidayListDTO implements Serializable{

public String siteStatus;
public String country;
public String location;
public Date holiday_date;
public String day;
public String occasion;
public String getSiteStatus() {
return siteStatus;
}
public void setSiteStatus(String siteStatus) {
this.siteStatus = siteStatus;
}
public String getCountry() {
return country;
}
public void setCountry(String country) {
this.country = country;
}
public String getLocation() {
return location;
}
public void setLocation(String location) {
this.location = location;
}
public Date getHoliday_date() {
return holiday_date;
}
public void setHoliday_date(Date holidayDate) {
holiday_date = holidayDate;
}
public String getDay() {
return day;
}
public void setDay(String day) {
this.day = day;
}
public String getOccasion() {
return occasion;
}
public void setOccasion(String occasion) {
this.occasion = occasion;
}


}

Sample Excel file(sheet) to be read by the above code using POI HSSF API....

SiteStatus country location date day occasion
offsite india chennai 10/12/2010 Monday Ramzan
onsite us new jersy 11/12/2010 Tuesday Rangoli
offsite india delhi 9/11/2010 Wednesday deepavali