之前寫過一篇關於如何匯出大資料的部落格，最近因為工作需要，又有匯入的需求。網上查了很多資料，後來發現POI提供瞭解決方案，大致思路是，excel2007之後，其實是由xml組成的，把excel的副檔名改成zip,再解壓，就能看到裡面的xml。主要有兩類xml，一類是儲存常量的xml，名字叫 shareStrings.xml，大至如下：

<?xml version="1.0" encoding="utf-8"?>

<sst xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main" count="38" uniqueCount="26">
  <si>
    <t>型別</t>
  </si>
  <si>
    <t>數量</t>
  </si>
  <si>
    <t>abdefga</t>
    <phoneticPr fontId="1" type="noConversion"/>
  </si>
</sst>
 

<?xml version="1.0" encoding="utf-8"?>

<worksheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main" xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:x14ac="http://schemas.microsoft.com/office/spreadsheetml/2009/9/ac" mc:Ignorable="x14ac">
  <dimension ref="A1:N5"/>
  <sheetViews>
    <sheetView tabSelected="1" topLeftCell="C1" workbookViewId="0">
      <selection activeCell="K15" sqref="K15"/>
    </sheetView>
  </sheetViews>
  <sheetFormatPr defaultRowHeight="13.5" x14ac:dyDescent="0.15"/>
  <cols>
    <col min="1" max="2" width="9" style="3"/>
    <col min="3" max="3" width="24.375" style="3" customWidth="1"/>
    <col min="4" max="4" width="9" style="3"/>
  </cols>
  <sheetData>
    <row r="1" spans="1:14" x14ac:dyDescent="0.15">
      <c r="A1" s="3" t="s">
        <v>0</v>
      </c>
      <c r="B1" s="3" t="s">
        <v>1</v>
      </c>   
    </row>
  </sheetData>
  <phoneticPr fontId="1" type="noConversion"/>
  <pageMargins left="0.7" right="0.7" top="0.75" bottom="0.75" header="0.3" footer="0.3"/>
  <pageSetup paperSize="9" orientation="portrait" r:id="rId1"/>
</worksheet>
 

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

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.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;



/**
 * A rudimentary XLSX -> CSV processor modeled on the
 * POI sample program XLS2CSVmra by Nick Burch from the
 * package org.apache.poi.hssf.eventusermodel.examples.
 * Unlike the HSSF version, this one completely ignores
 * missing rows.
 * <p/>
 * Data sheets are read using a SAX parser to keep the
 * memory footprint relatively small, so this should be
 * able to read enormous workbooks.  The styles table and
 * the shared-string table must be kept in memory.  The
 * standard POI styles table class is used, but a custom
 * (read-only) class is used for the shared string table
 * because the standard POI SharedStringsTable grows very
 * quickly with the number of unique strings.
 * <p/>
 * Thanks to Eric Smith for a patch that fixes a problem
 * triggered by cells with multiple "t" elements, which is
 * how Excel represents different formats (e.g., one word
 * plain and one word bold).
 * 
 * @author Chris Lott
 */
public class CopyOfXLSX2CSV {
	private static final Logger logger = new Logger(CopyOfXLSX2CSV.class);

    /**
     * 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 CommonException extends RuntimeException {

        /**
         *
         */
        private static final long serialVersionUID = 1L;

        private String code;

        private String desc;

        public CommonException(String code, String desc) {
            this.code = code;
            this.desc = desc;
        }


        public String getCode() {
            return code;
        }

        public void setCode(String code) {
            this.code = code;
        }

        public String getDesc() {
            return desc;
        }

        public void setDesc(String desc) {
            this.desc = desc;
        }

        @Override
        public String getMessage() {
            return desc;
        }

    }
    
    /**
     * Derived from http://poi.apache.org/spreadsheet/how-to.html#xssf_sax_api
     * <p/>
     * Also see Standard ECMA-376, 1st edition, part 4, pages 1928ff, at
     * http://www.ecma-international.org/publications/standards/Ecma-376.htm
     * <p/>
     * A web-friendly version is http://openiso.org/Ecma/376/Part4
     */
    class MyXSSFSheetHandler extends DefaultHandler {

        /**
         * Table with styles
         */
        private StylesTable stylesTable;

        /**
         * Table with unique strings
         */
        private ReadOnlySharedStringsTable sharedStringsTable;

        /**
         * Destination for data
         */
        private final ExcelDealAction action;

        /**
         * 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;
        
        private Integer dealSize;

        private String[] row; 
        private List<String[]> data;
        //執行緒池
        private ExecutorService fixedThreadPool ;
        //是否只取第一行
        private boolean isFirstRow;
        
        private int beginSize=0;
        /**
         * Accepts objects needed while parsing.
         *
         * @param styles  Table of styles
         * @param strings Table of shared strings
         * @param cols    Minimum number of columns to show
         * @param target  Sink for output
         */
        public MyXSSFSheetHandler(
                StylesTable styles,
                ReadOnlySharedStringsTable strings,
                int cols,
                ExcelDealAction action,
                Integer dealSize,boolean isFirstRow) {
            this.stylesTable = styles;
            this.sharedStringsTable = strings;
            this.minColumnCount = cols;
            this.action = action;
            this.value = new StringBuffer();
            this.nextDataType = xssfDataType.NUMBER;
            this.formatter = new DataFormatter();
            this.dealSize=dealSize;
            this.isFirstRow=isFirstRow;
            this.row=new String[cols];
            data=new ArrayList<String[]>();
            int threadno=isFirstRow?1:Runtime.getRuntime().availableProcessors();
            fixedThreadPool=Executors.newFixedThreadPool(threadno);
            logger.info("執行緒池的初始化資料為:",threadno);
            beginSize=0;
        }

        /*
           * (non-Javadoc)
           * @see org.xml.sax.helpers.DefaultHandler#startElement(java.lang.String, java.lang.String, java.lang.String, org.xml.sax.Attributes)
           */
        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);
                }
            }

        }

        /*
           * (non-Javadoc)
           * @see org.xml.sax.helpers.DefaultHandler#endElement(java.lang.String, java.lang.String, java.lang.String)
           */
        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() + '"';
                        break;

                    case FORMULA:
                        // A formula could result in a string value,
                        // so always add double-quote characters.
                        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() + '"';
                        break;

                    case SSTINDEX:
                        String sstIndex = value.toString();
                        try {
                            int idx = Integer.parseInt(sstIndex);
                            XSSFRichTextString rtss = new XSSFRichTextString(sharedStringsTable.getEntryAt(idx));
                            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 + ")";
                        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)
                	row[thisColumn]=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(',');
                    	this.data.add(row);
                    	this.row=new String[this.minColumnCount];
                    	if(this.isFirstRow){
                    		this.action.dealList(data,0);
                    		/**
                    		 * 需要自己定義的一個異常來中斷讀取
                    		 */
                    		throw new CommonException("", "已取出第一行,中斷執行緒");
                    	}else{
                    		if(this.data.size()==this.dealSize){
                    			/**
                    			 * 用執行緒來執行
                    			 */
                    			fixedThreadPool.execute(new dealActionThread(this.data,this.beginSize, action));
                    			this.beginSize+=this.data.size();
                    			this.data=new ArrayList<String[]>();
                    		}
                    	}
                    }
                }

                // We're onto a new row
//                output.println();
                lastColumnNumber = -1;
            }

        }

        
        @Override
		public void endDocument() throws SAXException {
			super.endDocument();
			this.action.dealList(data,this.beginSize);
			fixedThreadPool.shutdown();
			try {
				fixedThreadPool.awaitTermination(Long.MAX_VALUE, TimeUnit.DAYS);
			} catch (InterruptedException e) {
				e.printStackTrace();
			} 
		}

		/**
         * Captures characters only if a suitable element is open.
         * Originally was just "v"; extended for inlineStr also.
         */
        public void characters(char[] ch, int start, int length)
                throws SAXException {
            if (vIsOpen)
                value.append(ch, start, length);
        }

        /**
         * Converts an Excel column name like "C" to a zero-based index.
         *
         * @param name
         * @return Index corresponding to the specified name
         */
        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;
        }

    }
    
    class dealActionThread implements Runnable{
    	private List<String[]> dealList;
    	private ExcelDealAction action;
    	private int beginSize;
    	
    	public dealActionThread(List<String[]> dealList,int beginSize,ExcelDealAction action){
    		this.dealList=dealList;
    		this.action=action;
    		this.beginSize=beginSize;
    	}
		@Override
		public void run() {
			this.action.dealList(this.dealList,beginSize);
		}
    	
    }

    ///////////////////////////////////////

    private OPCPackage xlsxPackage;
    private int minColumns;
    private ExcelDealAction action;
    private int dealSize;
    private boolean isFirst;
    /**
     * 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 CopyOfXLSX2CSV(OPCPackage pkg, ExcelDealAction action, int minColumns,int dealSize,boolean isFirst) {
        this.xlsxPackage = pkg;
        this.action = action;
        this.minColumns = minColumns;
        this.dealSize=dealSize;
        this.isFirst=isFirst;
    }

    /**
     * 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.action,this.dealSize,this.isFirst);
        sheetParser.setContentHandler(handler);
        sheetParser.parse(sheetSource);
    }

    /**
     * Initiates the processing of the XLS workbook file to CSV.
     *
     * @throws IOException
     * @throws OpenXML4JException
     * @throws ParserConfigurationException
     * @throws SAXException
     */
    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();
        while (iter.hasNext()) {
            InputStream stream = iter.next();
            String sheetName = iter.getSheetName();
            logger.info("處理表單:",sheetName);
            processSheet(styles, strings, stream);
            stream.close();
        }
    }

    public static void main(String[] args) throws Exception {
        File xlsxFile = new File("d:/at2.xlsx");
        //列數
        int minColumns = 14;
       //一次處理的數量 
       int dealSize=1000;
        long begin =System.currentTimeMillis();
        OPCPackage p = OPCPackage.open(xlsxFile.getPath(), PackageAccess.READ);
		CopyOfXLSX2CSV xlsx2csv = new CopyOfXLSX2CSV(p, new ExcelDealAction() {
			@Override
			public void dealList(List<String[]> data,int beginSize) {
				System.out.println("***********"+":"+data.size());	
				for(int i=0;i<data.size();i++){
					System.out.println(data.get(i)[4]);
				}
			}
		}, minColumns,dealSize,false);//最後一個引數是是否只讀取第一行，為了讀取欄位名行加的
		xlsx2csv.process();
		System.out.println("耗時:"+(System.currentTimeMillis()-begin));
	}

}