一、背景
在开发过程中经常有遇到需要将Excel转换成csv形式，Excel中的格式有.xlsx和.xls两种，关于这方面的框架有很多，有的只能转其中的一种格式、有的需要钱；这些估计都是次要的，最主要还是需要看他们的性能，有的需要很大的并发量、有的需要上传很大的数据量、有的又需要上传的速度。当然他们的好处各有不同，我们选择其中一种最关注的是使用方便，在自己的业务场景下效率还非常的OK，那就是最适合自己的。下面分享下我们公司常用的一种方式POI。
二、依赖
<dependencies>
<dependency>
<groupId>net.sf.opencsv</groupId>
<artifactId>opencsv</artifactId>
<version>2.1</version>
</dependency>
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>ooxml-schemas</artifactId>
<version>1.1</version>
<type>pom</type>
</dependency>
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi</artifactId>
<version>3.7</version>
</dependency>
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>ooxml-schemas</artifactId>
<version>1.1</version>
</dependency>
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml</artifactId>
<version>3.7</version>
</dependency>
<dependency>
<groupId>dom4j</groupId>
<artifactId>dom4j</artifactId>
<version>1.6.1</version>
</dependency>
</dependencies>三、代码
package com.shangjian.mps.sap.utils;
import org.apache.poi.openxml4j.exceptions.OpenXML4JException;
import org.apache.poi.openxml4j.opc.OPCPackage;
import org.apache.poi.openxml4j.opc.PackageAccess;
import org.apache.poi.ss.usermodel.BuiltinFormats;
import org.apache.poi.ss.usermodel.DataFormatter;
import org.apache.poi.xssf.eventusermodel.ReadOnlySharedStringsTable;
import org.apache.poi.xssf.eventusermodel.XSSFReader;
import org.apache.poi.xssf.model.StylesTable;
import org.apache.poi.xssf.usermodel.XSSFCellStyle;
import org.apache.poi.xssf.usermodel.XSSFRichTextString;
import org.xml.sax.*;
import org.xml.sax.helpers.DefaultHandler;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintStream;
/**
* @Title: TODO
* @ClassName XLSX2CSV
* @Date 2022/9/29 15:32
* @Version 1.0
*/
public class XLSX2CSV {
/**
* The type of the data value is indicated by an attribute on the cell. The
* value is usually in a "v" element within the cell.
*/
enum xssfDataType {
BOOL, ERROR, FORMULA, INLINESTR, SSTINDEX, NUMBER,
}
class MyXSSFSheetHandler extends DefaultHandler {
/**
* Table with styles
*/
private StylesTable stylesTable;
/**
* Table with unique strings
*/
private ReadOnlySharedStringsTable sharedStringsTable;
/**
* Destination for data
*/
private final PrintStream output;
/**
* Number of columns to read starting with leftmost
*/
private final int minColumnCount;
// Set when V start element is seen
private boolean vIsOpen;
// Set when cell start element is seen;
// used when cell close element is seen.
private xssfDataType nextDataType;
// Used to format numeric cell values.
private short formatIndex;
private String formatString;
private final DataFormatter formatter;
private int thisColumn = -1;
// The last column printed to the output stream
private int lastColumnNumber = -1;
// Gathers characters as they are seen.
private StringBuffer value;
public MyXSSFSheetHandler(StylesTable styles,
ReadOnlySharedStringsTable strings, int cols, PrintStream target) {
this.stylesTable = styles;
this.sharedStringsTable = strings;
this.minColumnCount = cols;
this.output = target;
this.value = new StringBuffer();
this.nextDataType = xssfDataType.NUMBER;
this.formatter = new DataFormatter();
}
public void startElement(String uri, String localName, String name,
Attributes attributes) throws SAXException {
if ("inlineStr".equals(name) || "v".equals(name)) {
vIsOpen = true;
// Clear contents cache
value.setLength(0);
}
// c => cell
else if ("c".equals(name)) {
// Get the cell reference
String r = attributes.getValue("r");
int firstDigit = -1;
for (int c = 0; c < r.length(); ++c) {
if (Character.isDigit(r.charAt(c))) {
firstDigit = c;
break;
}
}
thisColumn = nameToColumn(r.substring(0, firstDigit));
// Set up defaults.
this.nextDataType = xssfDataType.NUMBER;
this.formatIndex = -1;
this.formatString = null;
String cellType = attributes.getValue("t");
String cellStyleStr = attributes.getValue("s");
if ("b".equals(cellType))
nextDataType = xssfDataType.BOOL;
else if ("e".equals(cellType))
nextDataType = xssfDataType.ERROR;
else if ("inlineStr".equals(cellType))
nextDataType = xssfDataType.INLINESTR;
else if ("s".equals(cellType))
nextDataType = xssfDataType.SSTINDEX;
else if ("str".equals(cellType))
nextDataType = xssfDataType.FORMULA;
else if (cellStyleStr != null) {
// It's a number, but almost certainly one
// with a special style or format
int styleIndex = Integer.parseInt(cellStyleStr);
XSSFCellStyle style = stylesTable.getStyleAt(styleIndex);
this.formatIndex = style.getDataFormat();
this.formatString = style.getDataFormatString();
if (this.formatString == null)
this.formatString = BuiltinFormats
.getBuiltinFormat(this.formatIndex);
}
}
}
public void endElement(String uri, String localName, String name)
throws SAXException {
String thisStr = null;
// v => contents of a cell
if ("v".equals(name)) {
// Process the value contents as required.
// Do now, as characters() may be called more than once
switch (nextDataType) {
case BOOL:
char first = value.charAt(0);
thisStr = first == '0' ? "FALSE" : "TRUE";
break;
case ERROR:
// thisStr = "\"ERROR:" + value.toString() + '"';
thisStr = "\"ERROR:" + value.toString() + '"';
break;
case FORMULA:
// A formula could result in a string value,
// so always add double-quote characters.
// thisStr = '"' + value.toString() + '"';
thisStr = value.toString();
break;
case INLINESTR:
// TODO: have seen an example of this, so it's untested.
XSSFRichTextString rtsi = new XSSFRichTextString(value
.toString());
// thisStr = '"' + rtsi.toString() + '"';
thisStr = rtsi.toString();
break;
case SSTINDEX:
String sstIndex = value.toString();
try {
int idx = Integer.parseInt(sstIndex);
XSSFRichTextString rtss = new XSSFRichTextString(
sharedStringsTable.getEntryAt(idx));
// thisStr = '"' + rtss.toString() + '"';
thisStr = rtss.toString() ;
} catch (NumberFormatException ex) {
output.println("Failed to parse SST index '" + sstIndex
+ "': " + ex.toString());
}
break;
case NUMBER:
String n = value.toString();
if (this.formatString != null)
thisStr = formatter.formatRawCellContents(Double
.parseDouble(n), this.formatIndex,
this.formatString);
else
thisStr = n;
break;
default:
// thisStr = "(TODO: Unexpected type: " + nextDataType + ")";
thisStr = "(TODO: Unexpected type: " + nextDataType + ")";
break;
}
// Output after we've seen the string contents
// Emit commas for any fields that were missing on this row
if (lastColumnNumber == -1) {
lastColumnNumber = 0;
}
for (int i = lastColumnNumber; i < thisColumn; ++i)
output.print(',');
// Might be the empty string.
output.print(thisStr);
// Update column
if (thisColumn > -1)
lastColumnNumber = thisColumn;
} else if ("row".equals(name)) {
// Print out any missing commas if needed
if (minColumns > 0) {
// Columns are 0 based
if (lastColumnNumber == -1) {
lastColumnNumber = 0;
}
for (int i = lastColumnNumber; i < (this.minColumnCount); i++) {
output.print(',');
}
}
// We're onto a new row
output.println();
lastColumnNumber = -1;
}
}
public void characters(char[] ch, int start, int length)
throws SAXException {
if (vIsOpen)
value.append(ch, start, length);
}
private int nameToColumn(String name) {
int column = -1;
for (int i = 0; i < name.length(); ++i) {
int c = name.charAt(i);
column = (column + 1) * 26 + c - 'A';
}
return column;
}
}
// /
private OPCPackage xlsxPackage;
private int minColumns;
private PrintStream output;
private final String OUTPUT_CHARSET = "UTF-8";
/**
* Creates a new XLSX -> CSV converter
*
* @param pkg
* The XLSX package to process
* @param output
* The PrintStream to output the CSV to
* @param minColumns
* The minimum number of columns to output, or -1 for no minimum
*/
public XLSX2CSV(OPCPackage pkg, PrintStream output, int minColumns) {
this.xlsxPackage = pkg;
this.output = output;
this.minColumns = minColumns;
}
//TODO catch exceptions
public XLSX2CSV(String inputFilePath, String outputFilePath) throws Exception {
xlsxPackage = OPCPackage.open(inputFilePath, PackageAccess.READ);
output = new PrintStream(outputFilePath, OUTPUT_CHARSET);
minColumns = -1;
}
/**
* Parses and shows the content of one sheet using the specified styles and
* shared-strings tables.
*
* @param styles
* @param strings
* @param sheetInputStream
*/
public void processSheet(StylesTable styles,
ReadOnlySharedStringsTable strings, InputStream sheetInputStream)
throws IOException, ParserConfigurationException, SAXException {
InputSource sheetSource = new InputSource(sheetInputStream);
SAXParserFactory saxFactory = SAXParserFactory.newInstance();
SAXParser saxParser = saxFactory.newSAXParser();
XMLReader sheetParser = saxParser.getXMLReader();
ContentHandler handler = new MyXSSFSheetHandler(styles, strings,
this.minColumns, this.output);
sheetParser.setContentHandler(handler);
sheetParser.parse(sheetSource);
}
public void process() throws IOException, OpenXML4JException,
ParserConfigurationException, SAXException {
ReadOnlySharedStringsTable strings = new ReadOnlySharedStringsTable(
this.xlsxPackage);
XSSFReader xssfReader = new XSSFReader(this.xlsxPackage);
StylesTable styles = xssfReader.getStylesTable();
XSSFReader.SheetIterator iter = (XSSFReader.SheetIterator) xssfReader
.getSheetsData();
int index = 0;
while (iter.hasNext()) {
InputStream stream = iter.next();
String sheetName = iter.getSheetName();
// this.output.println();
// this.output.println(sheetName + " [index=" + index + "]:");
processSheet(styles, strings, stream);
stream.close();
++index;
}
}
public static void trans(String fileInput,String fileOutput){
XLSX2CSV xlsx2csv = null;
try {
xlsx2csv = new XLSX2CSV(fileInput, fileOutput);
} catch (Exception e) {
e.printStackTrace();
}
try {
xlsx2csv.process();
} catch (IOException e) {
e.printStackTrace();
} catch (OpenXML4JException e) {
e.printStackTrace();
} catch (ParserConfigurationException e) {
e.printStackTrace();
} catch (SAXException e) {
e.printStackTrace();
}
}
}package com.shangjian.mps.sap.utils;
import jxl.Cell;
import jxl.Sheet;
import jxl.Workbook;
import jxl.WorkbookSettings;
import java.io.*;
import java.util.Locale;
/**
* @Title: TODO
* @ClassName Excel2Csv
* @Date 2022/9/29 15:34
* @Version 1.0
*/
public class Excel2Csv {
/**
*将excel(xls/xlsx)转换成csv文件
* @param excelFile
* @param csvFile
* @return String
*/
public static String getCsv(String excelFile, String csvFile) {
//.xlsx文件后缀转成csv
if (excelFile.endsWith(".xlsx")){
XLSX2CSV.trans(excelFile,csvFile);
return csvFile;
}
//.xls文件后缀转成csv
else {
try {
OutputStream os = new FileOutputStream(new File(csvFile));
OutputStreamWriter osw = new OutputStreamWriter(os, "UTF8");
BufferedWriter bw = new BufferedWriter(osw);
// 载入Excel文件
WorkbookSettings ws = new WorkbookSettings();
ws.setLocale(new Locale("en", "EN"));
Workbook wk = Workbook.getWorkbook(new File(excelFile), ws);
// 从工作簿(workbook)取得每页(sheets)
for (int sheet = 0; sheet < wk.getNumberOfSheets(); sheet++) {
Sheet s = wk.getSheet(sheet);
Cell[] row = null;
// 从每页(sheet)取得每个区块(Cell)
for (int i = 0; i < s.getRows(); i++) {
row = s.getRow(i);
if (row.length > 0) {
bw.write(row[0].getContents());
for (int j = 1; j < row.length; j++) {
//写入分隔符
bw.write(',');
bw.write(row[j].getContents());
}
}
bw.newLine();
}
}
bw.flush();
bw.close();
os.close();
osw.close();
} catch (Exception e) {
System.err.println(e.toString());
e.printStackTrace();
}
return csvFile;
}
}
}四、使用
public static void main(String[] args) {
Excel2Csv.getCsv("C:\\Users\\Jason\\Desktop\\新建文件夹\\物料齐套查询.xlsx", "C:\\Users\\Jason\\Desktop\\新建文件夹\\test6" +
".csv");
CsvReader csvRows = new CsvReader();
CsvData read = csvRows.read(new File("C:\\Users\\Jason\\Desktop\\新建文件夹\\test6.csv"));
List<CsvRow> rows = read.getRows();
System.out.println("rows = " + rows);
}