基于 XSSF和SAX（Event API） 读取excel 2007

简单封装sax的读取方式，没有含金量，因为完全没看懂。。。

官网文档：http://poi.apache.org/spreadsheet/how-to.html#XSSF+and+SAX+%28Event+API%29

只读第一页

package com.cuimi.auth.utils;

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this work for additional information regarding copyright ownership.
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import java.io.InputStream;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import javax.xml.parsers.ParserConfigurationException;

import org.apache.poi.openxml4j.opc.OPCPackage;
import org.apache.poi.openxml4j.opc.PackageAccess;
import org.apache.poi.util.SAXHelper;
import org.apache.poi.xssf.eventusermodel.XSSFReader;
import org.apache.poi.xssf.model.SharedStringsTable;
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;

/**
 * XSSF and SAX (Event API) basic example. See {@link XLSX2CSV} for a fuller
 * example of doing XSLX processing with the XSSF Event code.
 */
public class ReadExcelBySAX {
	static List<List<String>> dataList = null;
	static List<String> rowList = null;
	static String flag = "0";// 用于区分 当前的数据是第几行的

	public void processFirstSheet(String filename) throws Exception {
		try (OPCPackage pkg = OPCPackage.open(filename, PackageAccess.READ)) {
			XSSFReader r = new XSSFReader(pkg);
			SharedStringsTable sst = r.getSharedStringsTable();

			XMLReader parser = fetchSheetParser(sst);

			// process the first sheet
			try (InputStream sheet = r.getSheetsData().next()) {
				InputSource sheetSource = new InputSource(sheet);
				parser.parse(sheetSource);
			}
		}
	}

	// public void processAllSheets(String filename) throws Exception {
	// try (OPCPackage pkg = OPCPackage.open(filename, PackageAccess.READ)) {
	// XSSFReader r = new XSSFReader(pkg);
	// SharedStringsTable sst = r.getSharedStringsTable();
	//
	// XMLReader parser = fetchSheetParser(sst);
	//
	// Iterator<InputStream> sheets = r.getSheetsData();
	// while (sheets.hasNext()) {
	// System.out.println("Processing new sheet:\n");
	// try (InputStream sheet = sheets.next()) {
	// InputSource sheetSource = new InputSource(sheet);
	// parser.parse(sheetSource);
	// }
	// System.out.println("");
	// }
	// }
	// }

	public XMLReader fetchSheetParser(SharedStringsTable sst) throws SAXException, ParserConfigurationException {
		XMLReader parser = SAXHelper.newXMLReader();
		ContentHandler handler = new SheetHandler(sst);
		parser.setContentHandler(handler);
		return parser;
	}

	/**
	 * See org.xml.sax.helpers.DefaultHandler javadocs
	 */
	private static class SheetHandler extends DefaultHandler {
		private final SharedStringsTable sst;
		private String lastContents;
		private boolean nextIsString;
		private boolean inlineStr;
		private final LruCache<Integer, String> lruCache = new LruCache<>(50);

		private static class LruCache<A, B> extends LinkedHashMap<A, B> {
			private final int maxEntries;

			public LruCache(final int maxEntries) {
				super(maxEntries + 1, 1.0f, true);
				this.maxEntries = maxEntries;
			}

			@Override
			protected boolean removeEldestEntry(final Map.Entry<A, B> eldest) {
				return super.size() > maxEntries;
			}
		}

		private SheetHandler(SharedStringsTable sst) {
			this.sst = sst;
		}

		// 获取结尾的数字
		static String getMatchValue(String str) {
			// 按指定模式在字符串查找
			String pattern = "(\\d+$)";
			// 创建 Pattern 对象
			Pattern r = Pattern.compile(pattern);
			// 现在创建 matcher 对象
			Matcher m = r.matcher(str);
			if (m.find()) {
				return m.group();
			} else {
				return null;
			}
		}

		@Override
		public void startElement(String uri, String localName, String name, Attributes attributes) throws SAXException {
			// c => cell
			if (name.equals("c")) {
				// Print the cell reference
				String value = attributes.getValue("r");
				String columnNumber = getMatchValue(value);
				if (CmUtil.isValidString(columnNumber)) {
					if (!flag.equals(columnNumber)) {
						if (!rowList.isEmpty()) {
							dataList.add(rowList);
						}
						rowList = new ArrayList();
						flag = columnNumber;
					}
				}

				// System.out.print(value + " - ");

				// Figure out if the value is an index in the SST
				String cellType = attributes.getValue("t");
				nextIsString = cellType != null && cellType.equals("s");
				inlineStr = cellType != null && cellType.equals("inlineStr");
			}
			// Clear contents cache
			lastContents = "";
		}

		@Override
		public void endElement(String uri, String localName, String name) throws SAXException {
			// Process the last contents as required.
			// Do now, as characters() may be called more than once
			if (nextIsString) {
				Integer idx = Integer.valueOf(lastContents);
				lastContents = lruCache.get(idx);
				if (lastContents == null && !lruCache.containsKey(idx)) {
					lastContents = new XSSFRichTextString(sst.getEntryAt(idx)).toString();
					lruCache.put(idx, lastContents);
				}
				nextIsString = false;
			}

			// v => contents of a cell
			// Output after we've seen the string contents
			if (name.equals("v") || (inlineStr && name.equals("c"))) {
				// System.out.println(lastContents);// 值
				rowList.add(lastContents);
			}
		}

		@Override
		public void characters(char[] ch, int start, int length) throws SAXException { // NOSONAR
			lastContents += new String(ch, start, length);
		}
	}

	public static List<List<String>> getListForExcel(String filePath) {
		dataList = new ArrayList<List<String>>();
		rowList = new ArrayList<String>();

		ReadExcelBySAX howto = new ReadExcelBySAX();
		try {
			howto.processFirstSheet(filePath);
		} catch (Exception e) {
			e.printStackTrace();
			throw new RuntimeException("读取excel数据失败！");
		}
		return dataList;
	}

	public static void main(String[] args) throws Exception {
		dataList = getListForExcel("H:\\Desktop\\测试.xlsx");
		 System.out.println(dataList);
		// howto.processAllSheets(filename);
	}
}

打印结果：[[姓名,年龄,性别][小明,12,男][小方,11,男]]