Home PC Games Linux Windows Database Network Programming Server Mobile  
  Home \ Linux \ Apache POI Excel Document Processing     - MySQL query performance comparison of a single truth (Database)

- Use nice, cpulimit and cgroups limit cpu usage (Linux)

- Mumble installation source VoIP application on Ubuntu (Linux)

- Python KNN algorithm of actual realization (Programming)

- IO reference Docker container (Server)

- Python class of operator overloading (Programming)

- Installation and deployment of MariaDB under CentOS (Database)

- How to migrate MySQL to MariaDB under linux (Database)

- Cacti Linux-based system monitoring and alarm (Linux)

- Docker in the development and practice of IFTTT (Server)

- Gitlab installation under CentOS 7 (Linux)

- How to upgrade to Oracle 11g Oracle 12c (Database)

- CentOS5 installation Nodejs (Linux)

- MySQL function: group_concat () function (Database)

- Python when automated operation and maintenance often used method (Programming)

- How to experience Unity 8 Mir on Ubuntu 16.04 (Linux)

- GEC2440 easiest a kernel compile Linux2.6.30.4 (Programming)

- Varnish achieve page jump (Server)

- Use Linux built-in firewall to improve network access control (Linux)

- Linux memory management -free learning experience (Linux)

  Apache POI Excel Document Processing
  Add Date : 2018-11-21      
  Currently popular treatment excel document, there are two general ways, namely POI and JXL. Heavyweight POI advantages and disadvantages: suitable for excel document details a relatively professional requirements, such as using formulas, macros and other advanced features; drawback is that the operation is relatively cumbersome, non-pure java prepared rack package, cross-platform needs to be strengthened. Lightweight JXL disadvantages: Jxl pure javaAPI, excellent cross-platform, the operation is relatively simple; drawback is that does not support some of the advanced features excel document, but to meet the daily needs. Here we introduce the basic use of the POI.

1. First, import the relevant frame package

Also note that this version of the JDK you what development projects is to download different versions according to the corresponding POI JDK version.

2. Operation ExcelReader helper class can handle xls and xlsx files, readExcelTitle (InputStream is) Reads the file header, which is the first line of the file, readExcelContent (InputStream is) method to read the contents of the file:

import java.io.IOException;
import java.io.InputStream;
import java.text.DecimalFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.LinkedHashMap;
import java.util.Map;
import org.apache.log4j.Logger;
import org.apache.poi.ss.usermodel.Cell;
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.ss.usermodel.WorkbookFactory;
/ **
 * Operation Excel spreadsheet functionality class
 * /
public class ExcelReader {
    private static DecimalFormat df = new DecimalFormat ( "0");
    private final static Logger log = Logger.getLogger (ExcelReader.class);
    private Workbook wb = null;
    private Sheet sheet = null;
    private Row row = null;
    / **
    * Read the contents of an Excel spreadsheet header
    * @param InputStream
    * @return String array header content
    * @throws IOException
    * /
    public String [] readExcelTitle (InputStream is) throws Exception {
        try {
            wb = WorkbookFactory.create (is);
        } Catch (IOException e) {
            log.error ( "read the contents of Excel spreadsheet header abnormal", e);
            throw e;
        sheet = wb.getSheetAt (0);
        row = sheet.getRow (0);
        The total number of columns // heading
        int colNum = row.getPhysicalNumberOfCells ();
        String [] title = new String [colNum];
        for (int i = 0; i             title [i] = getCellFormatValue (row.getCell (i));
        log.info ( "read the contents of the complete Excel table header");
        return title;
    / **
    * Read Excel data content
    * @param InputStream
    * @return Map Map object that contains the cell data content
    * @throws IOException
    * /
    public Map readExcelContent (InputStream is) throws Exception {
        Map content = new LinkedHashMap ();
        String str = "";
        try {
            wb = WorkbookFactory.create (is);
        } Catch (IOException e) {
            log.error ( "read Excel data content", e);
            throw e;
        sheet = wb.getSheetAt (0);
        // Get the total number of rows
        int rowNum = sheet.getLastRowNum ();
        row = sheet.getRow (0);
        int colNum = row.getPhysicalNumberOfCells ();
        // Body content should start from the second row, first row header title
        for (int i = 1; i <= rowNum; i ++) {
            row = sheet.getRow (i);
            int j = 0;
            while (j                 // The data contents of each cell with a "-" separated, String class replace when needed for future use () method to restore data
                // You can also set the data to each cell in a javabean attribute, then you need to create a javabean
                // Str + = getStringCellValue (row.getCell ((short) j)). Trim () +
                // "-";
                if (row! = null) {
                    . Str + = getCellFormatValue (row.getCell (j)) trim () + ",";
                } Else {
                    str + = "" + ",";
                j ++;
            content.put (i, str.substring (0, str.length () - 1));
            str = "";
        log.info ( "read Excel data content complete");
        return content;
    / **
    * Set the type of data based on Cell
    * @param Cell
    * @return
    * /
    private String getCellFormatValue (Cell cell) {
        String cellvalue = "";
        if (cell! = null) {
            Analyzing the current // Type Cell
            switch (cell.getCellType ()) {
            // If the current Type Cell is NUMERIC
            case Cell.CELL_TYPE_NUMERIC:
            case Cell.CELL_TYPE_FORMULA: {
                // Determine whether the current cell to Date
                if (DateUtil.isCellDateFormatted (cell)) {
                    // If the Date type is converted to a Data Format
                    // Method 1: The data format is like this with every minute of the time: 2015-12-18 0:00:00
                    // Cellvalue = cell.getDateCellValue () toLocaleString ().;
                    // Method 2: data format is like this when every minute without tape: 2011-10-12
                    Date date = cell.getDateCellValue ();
                    SimpleDateFormat sdf = new SimpleDateFormat ( "yyyy-MM-dd");
                    cellvalue = sdf.format (date);
                // If it is a pure digital
                else {
                    // Get the current value of the Cell
                    cellvalue = String.valueOf (df.format (cell.getNumericCellValue ()));
            // If the current Type Cell is STRIN
            case Cell.CELL_TYPE_STRING:
                // Get the current Cell strings
                cellvalue = cell.getRichStringCellValue () getString ().;
            // Default value of Cell
                cellvalue = "";
        } Else {
            cellvalue = "";
        return cellvalue;

Simple example code, the actual use of exception handling mechanism should be added:
12345678910111213 FileInputStream is = new FileInputStream (file);
    ExcelReader excelReader = new ExcelReader ();
    String [] title = excelReader.readExcelTitle (is); // read the file title (non-file name, but the first line of the file)
    for (String str: title) {
    System.out.println (str);
    is.close ();
    is = new FileInputStream (file);
    Map map = excelReader.readExcelContent (is); // read the contents of the file
    for (int i = 1; i <= map.size (); i ++) {
        System.out.println (map.get (i));
    is.close ();
- Computer black magic: tail recursion (Programming)
- Oracle 11g maintenance partitions - Adding Partitions (Database)
- Linux based exercises, interview questions (Linux)
- Linux, modify the fstab file system can not start causing solve one case (Linux)
- Save the database data files into Oracle Learning (Database)
- Free compiler install MySQL-5.6.14 (Database)
- MySQL and MariaDB new master from the cluster configuration GTID (Database)
- When the master key encounter NULL (Database)
- CentOS source installation GitLab Chinese Version (Server)
- Java by Spy Memcached to cache data (Programming)
- Oracle11g CRS-0184 Problem Solving (Database)
- VirtualBox - Linux system virtual machine shared folders (Linux)
- Upgrade to Linux Mint 16 petra Mint 17 Qiana (Linux)
- Several back door and log tool under Linux (Linux)
- MySQL binlog group to submit XA (two-phase commit) (Database)
- Oracle 11g dataguard main library backup and recovery to the test environment in one database error (Database)
- Virtual Judge environment to build and configure under Ubuntu (Server)
- Linux Getting Started Tutorial: Ubuntu laptop screen brightness adjustment (Linux)
- The mv command to move the directory two cases under Linux (Linux)
- FileZilla install on Ubuntu 14.10 (Linux)
  CopyRight 2002-2022 newfreesoft.com, All Rights Reserved.