解决poi读取excel2007出现内存溢出问题代码参考-范文大全|优秀作文-实用文体写作网

更新时间:2023-07-20 20:26:29 阅读：评论：0

AbstractExcel2007Writer.java

package l.outofmemory;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.FileWriter;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.io.Writer;

import java.util.Calendar;

import java.util.Enumeration;

import java.util.zip.ZipEntry;

import java.util.zip.ZipFile;

import java.util.zip.ZipOutputStream;

import org.apache.poi.hssf.util.CellReference;

import org.apache.poi.ss.urmodel.DateUtil;

import org.apache.poi.xssf.urmodel.XSSFSheet;

import org.apache.poi.xssf.urmodel.XSSFWorkbook;

/**

* 抽象excel2007读入器，先构建.xlsx一张模板，改写模板中的l,使用这种方法

* 写入.xlsx文件，不需要太大的内存

*

*/

public abstract class AbstractExcel2007Writer {

private SpreadsheetWriter sw;

/**

* 写入电子表格的主要流程

* @param fileName

* @throws Exception

*/

public void process(String fileName) throws Exception{

// 建立工作簿和电子表格对象

XSSFWorkbook wb = new XSSFWorkbook();

XSSFSheet sheet = wb.createSheet("sheet1");

// 持有电子表格数据的xml文件名例如 /xl/l

String sheetRef = PackagePart().getPartName().getName();

// 保存模板

FileOutputStream os = new FileOutputStream("template.xlsx");

wb.write(os);

os.clo();

// 生成xml文件

File tmp = File.createTempFile("sheet", ".xml");

Writer fw = new FileWriter(tmp);

sw = new SpreadsheetWriter(fw);

generate();

fw.clo();

// 使用产生的数据替换模板

File templateFile = new File("template.xlsx");

FileOutputStream out = new FileOutputStream(fileName);

substitute(templateFile, tmp, sheetRef.substring(1), out);

out.clo();

//删除文件之前调用一下垃圾回收器，否则无法删除模板文件

System.gc();

// 删除临时模板文件

if (templateFile.isFile()&&ists()){

templateFile.delete();

}

/**

* 类使用者应该使用此方法进行写操作

* @throws Exception

*/

public abstract void generate() throws Exception;

public void beginSheet() throws IOException {

sw.beginSheet();

}

public void inrtRow(int rowNum) throws IOException {

sw.inrtRow(rowNum);

}

public void createCell(int columnIndex, String value) throws IOException {

sw.createCell(columnIndex, value, -1);

}

public void createCell(int columnIndex, double value) throws IOException {

sw.createCell(columnIndex, value, -1);

}

public void endRow() throws IOException {

sw.endRow();

}

public void endSheet() throws IOException {

sw.endSheet();

}

/**

*

* @param zipfile the template file

* @param tmpfile the XML file with the sheet data

* @param entry the name of the sheet entry to substitute, e.g. xl/l

* @param out the stream to write the result to

*/

private static void substitute(File zipfile, File tmpfile, String entry,

OutputStream out) throws IOException {

ZipFile zip = new ZipFile(zipfile);

ZipOutputStream zos = new ZipOutputStream(out);

@SuppressWarnings("unchecked")

Enumeration<ZipEntry> en = (Enumeration<ZipEntry>) ies();

while (en.hasMoreElements()) {

ZipEntry ze = en.nextElement();

if (!ze.getName().equals(entry)) {

zos.putNextEntry(new Name()));

InputStream is = InputStream(ze);

copyStream(is, zos);

is.clo();

}

zos.putNextEntry(new ZipEntry(entry));

InputStream is = new FileInputStream(tmpfile);

copyStream(is, zos);

is.clo();

zos.clo();

}

private static void copyStream(InputStream in, OutputStream out)

throws IOException {

byte[] chunk = new byte[1024];

int count;

while ((count = in.read(chunk)) >= 0) {

out.write(chunk, 0, count);

}

/**

* 在写入器中写入电子表格

*

*/

public static class SpreadsheetWriter {

private final Writer _out;

private int _rownum防已黄芪汤;

private static String LINE_SEPARATOR = System.getProperty("line.parator");

public SpreadsheetWriter(Writer out) {

_out = out;

}

public void beginSheet() throws IOException {

_out.write("<?xml version=\"1.0\" encoding=\"GB2312\"?>"

+ "<worksheet xmlns=\"schemas.openxmlformats/spreadsheetml/2006/main\">");

_out.write("<sheetData>"+LINE_SEPARATOR);

}

public void endSheet() throws IOException {

_out.write("</sheetData>");

_out.write("</worksheet>");

}

/**

* 插入新行

*

* @param rownum 以0开始

洗衣液十大品牌

*/

public void inrtRow(int rownum) throws IOException {

_out.write("<row r=\"" + (rownum + 1) + "\">"+LINE_SEPARATOR);

this._rownum = rownum;

}

/**

* 插入行结束标志

*/

public void endRow() throws IOException {

_out.write("</row>"+LINE_SEPARATOR);

}

/**

* 插入新列

* @param columnIndex

* @param value

* @param styleIndex

* @throws IOException

*/

public void createCell(int columnIndex, String value, int styleIndex)

throws IOException {

String ref = new CellReference(_rownum, columnIndex)

.formatAsString();

_out.write("<c r=\"" + ref + "\" t=\"inlineStr\"");

if (styleIndex != -1)

_out.write(" s=\"" + styleIndex + 名书推荐"\"");

_out.write(">");

_out.write("<is><t>"+XMLEncoder.encode(value)+"</t></is>");

_out.write("</c>");

}

public void createCell(int columnIndex, String value)

throws IOException {

createCell(columnIndex, value, -1);

}

public void createCell(int columnIndex, double value, int梦见和丈夫离婚 styleIndex)

throws IOException {

String ref = new CellReference(_rownum, columnIndex)

.formatAsString();

_out.write("<c r=\"" + ref + "\" t=\"n\"");

if (styleIndex != -1)

_out.write(" s=\"" + styleIndex + "\"");

_out.write(">");

_out.write("<v>" + value + "</v>");

_out.write("</c>");

}

public void createCell(int columnIndex, double value)

throws IOException {

createCell(columnIndex, value, -1);

}

public void createCell(int columnIndex, Calendar value, int styleIndex)

throws IOException {

createCell(columnIndex, DateUtil.getExcelDate(value, fal),

styleIndex);

}

Excel2003Reader.java

package l.outofmemory;

import java.io.FileInputStream;

import java.io.IOException;

import java.util.ArrayList;

import java.util.List;

import org.apache.poi.hssf.eventurmodel.FormatTrackingHSSFListener;

import org.apache.poi.hssf.eventurmodel.HSSFEventFactory;

import org.apache.poi.hssf.eventurmodel.HSSFListener;

import org.apache.poi.hssf.eventurmodel.HSSFRequest;

import org.apache.poi.hssf.eventurmodel.MissingRecordAwareHSSFListener;

import org.apache.poi.hssf.eventurmodel.EventWorkbookBuilder.SheetRecordCollectingListener;

import org.apache.poi.hssf.eventurmodel.dummyrecord.LastCellOfRowDummyRecord;

import org.apache.poi.hssf.eventurmodel.dummyrecord.MissingCellDummyRecord;

import org.apache.del.HSSFFormulaParr;

import org.apache.d.BOFRecord;

import org.apache.d.BlankRecord;

import org.apache.d.BoolErrRecord;

import org.apache.d.BoundSheetRecord;

import org.apache.d.FormulaRecord;

import org.apache.d.LabelRecord;

import org.apache.d.LabelSSTRecord;

import org.apache.d.NumberRecord;

import org.apache.d.Record;

import org.apache.d.SSTRecord;

import org.apache.d.StringRecord;

import org.apache.poi.hssf.urmodel.HSSFWorkbook;

import org.apache.poi.poifs.filesystem.POIFSFileSystem;

/**

* 抽象Excel2003读取器，通过实现HSSFListener监听器，采用事件驱动模式解析excel2003

* 中的内容，遇到特定事件才会触发，大大减少了内存的使用。

*

*/

public class Excel2003Reader implements HSSFListener{

private int minColumns = -1;

private POIFSFileSystem fs;

private int lastRowNumber;

private int lastColumnNumber;

/** Should we output the formula, or the value it has? */

private boolean outputFormulaValues = true;

/** For parsing Formulas */

private SheetRecordCollectingListener workbookBuildingListener;

//excel2003工作薄

private HSSFWorkbook stubWorkbook;

// Records we pick up as we process

private SSTRecord sstRecord;

private FormatTrackingHSSFListener formatListener;

//表索引

private int sheetIndex = -1;

private BoundSheetRecord[] orderedBSRs;

@SuppressWarnings("unchecked")

private ArrayList boundSheetRecords = new ArrayList();

// For handling formulas with string results

private int nextRow;

private int nextColumn;

private boolean outputNextStringRecord;

//当前行

private int curRow = 0;

//存储行记录的容器

private List<String> rowlist = new ArrayList<String>();;

@SuppressWarnings( "unud")

private String sheetName;

private IRowReader rowReader;

public void tRowReader(IRowReader rowReader){

this.rowReader = rowReader;

}

/**

* 遍历excel下所有的sheet

* @throws IOException

*/

public void process(String fileName) throws IOException {

this.fs = new POIFSFileSystem(new FileInputStream(fileName));

MissingRecordAwareHSSFListener listener = new MissingRecordAwareHSSFListener(

this);

formatListener = new FormatTrackingHSSFListener(listener);

HSSFEventFactory factory = new HSSFEventFactory();

HSSFRequest request = new HSSFRequest();

if (outputFormulaValues) {

request.addListenerForAllRecords(formatListener);

} el {

workbookBuildingListener = new SheetRecordCollectingListener(

formatListener);

request.addListenerForAllRecords(workbookBuildingListener);

}

factory.processWorkbookEvents(request, fs);

}

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/**

* HSSFListener 监听方法，处理 Record

*/

@SuppressWarnings("unchecked")

public void processRecord(Record record) {

int thisRow = -1;

int thisColumn = -1;

String thisStr = null;

String value = null;

switch (Sid()) {

ca BoundSheetRecord.sid:

boundSheetRecords.add(record);

break;

ca BOFRecord.sid:

BOFRecord br = (BOFRecord) record;

if (br.getType() == BOFRecord.TYPE_WORKSHEET) {

// 如果有需要，则建立子工作薄

if (workbookBuildingListener != null && stubWorkbook == null) {

stubWorkbook = workbookBuildingListener

.getStubHSSFWorkbook();

}

sheetIndex++;

if (orderedBSRs == null) {

orderedBSRs = BoundSheetRecord

.orderByBofPosition(boundSheetRecords);

}

sheetName = orderedBSRs[sheetIndex].getSheetname();

}

break;

ca SSTRecord.sid:

sstRecord = (SSTRecord) record;

break;

ca BlankRecord.sid:

BlankRecord brec = (BlankRecord) record;

thisRow = Row();

thisColumn = Column();

thisStr = "";

rowlist.add(thisColumn, thisStr);

break;

ca BoolErrRecord.sid: //单元格为布尔类型

BoolErrRecord berec = (BoolErrRecord) record;

thisRow = Row();

thisColumn = Column();

thisStr = BooleanValue()+"";

rowlist.add(thisColumn, thisStr);

break;

ca FormulaRecord.sid: //单元格为公式类型

FormulaRecord frec = (FormulaRecord) record;

thisRow = Row();

thisColumn = Column();

if (outputFormulaValues) {

if (Double.isNaN(Value())) {

// Formula result is a string

// This is stored in the next record

outputNextStringRecord = true;

nextRow = Row();

nextColumn = Column();

} el {

thisStr = formatListener.formatNumberDateCell(frec);

}

} el {

thisStr = '"' + HSSFFormulaParr.toFormulaString(stubWorkbook,

PardExpression()) + '"';

}

rowlist.add(thisColumn,thisStr);

break;

ca StringRecord.sid://单元格中公式的字符串

if (outputNextStringRecord) {

// String for formula

StringRecord srec = (StringRecord) record;

thisStr = String();

thisRow = nextRow;

thisColumn = nextColumn;

outputNextStringRecord = fal;

}

break;

ca LabelRecord.sid:

LabelRecord lrec = (LabelRecord) record;

curRow = thisRow = Row();

thisColumn = Column();

value = Value().trim();

value = value.equals("")?" ":value;

this.rowlist.add(thisColumn, value);

break;

ca LabelSSTRecord.sid: //单元格为字符串类型

LabelSSTRecord lsrec = (LabelSSTRecord) record;

curRow = thisRow = Row();

thisColumn = Column();

if (sstRecord == null) {

rowlist.add(thisColumn, " ");

} el {

value = sstRecord

.SSTIndex()).toString().trim();

value = value.equals("")?" ":value;

入住证明rowlist.add(thisColumn,value);

}

break;

ca NumberRecord.sid: //单元格为数字类型

NumberRecord numrec = (NumberRecord) record;

curRow = thisRow = Row();

thisColumn = Column();

value = formatListener.formatNumberDateCell(numrec).trim();

value = value.equals("")?" ":value;

// 向容器加入列值

rowlist.add(thisColumn, value);

break;

default:

break;

}

// 遇到新行的操作

if (thisRow != -1 && thisRow != lastRowNumber) {

lastColumnNumber = -1;

}

// 空值的操作

if (record instanceof MissingCellDummyRecord) {

MissingCellDummyRecord mc = (MissingCellDummyRecord) record;

curRow = thisRow = mc.getRow();

thisColumn = mc.getColumn();

rowlist.add(thisColumn," ");

}

// 更新行和列的值

if (thisRow > -1)

lastRowNumber = thisRow;

if (thisColumn > -1)

lastColumnNumber = thisColumn;

// 行结束时的操作

if (record instanceof LastCellOfRowDummyRecord) {

if (minColumns > 0) {

// 列值重新置空

if (lastColumnNumber == -1) {

lastColumnNumber = 0;

}

lastColumnNumber = -1;

// 每行结束时，调用getRows() 方法

rowReader.getRows(sheetIndex,curRow, rowlist);

// 清空容器

rowlist.clear();

}

Excel2003Writer.java

package l.outofmemory;

import java.io.FileOutputStream;

import java.io.IOException;

import org.apache.poi.hssf.urmodel.HSSFWorkbook;

import org.apache.poi.ss.urmodel.Cell;

import org.apache.poi.ss.urmodel.Row;

import org.apache.poi.ss.urmodel.Sheet;

import org.apache.poi.ss.urmodel.Workbook;

public class Excel2003Writer {

/**

* @param args

*/

public static void main(String[] args) {

try{

System.out.println("开始写入");

writeExcel("tes2003.xls");

System.out.println("写完xcel2003");

} catch (IOException e) {

}

/**

* 写入excel并填充内容,一个sheet只能写65536行以下，超出会报异常，写入时建议使用AbstractExcel2007Writer

* @param fileName

* @throws IOException

*/

public static void writeExcel(String fileName) throws IOException{

// 创建excel2003对象

Workbook wb = new HSSFWorkbook();

// 设置文件放置路径和文件名

FileOutputStream fileOut = new FileOutputStream(fileName);

// 创建新的表单

Sheet sheet = wb.createSheet("newsheet");

// 创建新行

for(int i=0;i<20000;i++){

Row row = ateRow(i);

// 创建单元格

Cell cell = ateCell(0);

// 设置单元格值

cell.tCellValue(1);

ateCell(1).tCellValue(1+i);

ateCell(2).tCellValue(true);

ateCell(3).tCellValue(0.43d);

ateCell(4).tCellValue('d');

ateCell(5).tCellValue("");

ateCell(6).tCellValue("第七列"+i);

ateCell(7).tCellValue("第八列"+i);

}

wb.write(fileOut);

fileOut.clo();

}

Excel2007Reader.java

package l.outofmemory;

import java.io.InputStream;

import java.math.BigDecimal;

import SimpleDateFormat;

import java.util.ArrayList;

import java.util.Date;

import java.util.Iterator;

import java.util.List;

import org.apache.poi.hssf.urmodel.HSSFDateUtil;

import org.apache.poi.openxml4j.opc.OPCPackage;

import org.apache.poi.xssf.eventurmodel.XSSFReader;

import org.apache.del.SharedStringsTable;

import org.apache.poi.xssf.urmodel.XSSFRichTextString;

import l.sax.Attributes;

import l.sax.InputSource;

import l.sax.SAXException;

import l.sax.XMLReader;

import l.sax.helpers.DefaultHandler;

import l.sax.helpers.XMLReaderFactory;

/**

* 抽象Excel2007读取器，excel2007的底层数据结构是xml文件，采用SAX的事件驱动的方法解析

* xml，需要继承DefaultHandler，在遇到文件内容时，事件会触发，这种做法可以大大降低

* 内存的耗费，特别使用于大数据量的文件。

*

*/

public class Excel2007Reader extends DefaultHandler {

//共享字符串表

private SharedStringsTable sst;

//上一次的内容

private String lastContents;

private boolean nextIsString;

private int sheetIndex = -1;

private List<String> rowlist = new ArrayList<String>();

//当前行

private int curRow = 0;

//当前列

private int curCol = 0;

//日期标志

private boolean dateFlag;

//数字标志

private boolean numberFlag;

private boolean isTElement;

private IRowReader rowReader;

public void tRowReader(IRowReader rowReader){

this.rowReader = rowReader;

}

/**只遍历一个电子表格，其中sheetId为要遍历的sheet索引，从1开始，1-3

* @param filename

* @param sheetId

* @throws Exception

*/

public void processOneSheet(String filename,int sheetId) throws Exception {

OPCPackage pkg = OPCPackage.open(filename);

XSSFReader r = new XSSFReader(pkg);

SharedStringsTable sst = r.getSharedStringsTable();

XMLReader parr = fetchSheetParr(sst);

// 根据 rId# 或 rSheet# 查找sheet

InputStream sheet2 = r.getSheet("rId"+sheetId);

sheetIndex++;

InputSource sheetSource = new InputSource(sheet2);

parr.par(sheetSource);

sheet2.clo();

}

/**

* 遍历工作簿中所有的电子表格

* @param filename

* @throws Exception

*/

public void process(String filename) throws Exception {

OPCPackage pkg = OPCPackage.open(filename);

XSSFReader r = new XSSFReader(pkg);

SharedStringsTable sst = r.getSharedStringsTable();

XMLReader parr = fetchSheetParr(sst);

Iterator<InputStream> sheets = r.getSheetsData();

while (sheets.hasNext()) {

curRow = 0;

sheetIndex++;

InputStream sheet = ();

InputSource sheetSource = new InputSource(sheet);

parr.par(sheetSource);

sheet.clo();

}

public XMLReader fetchSheetParr(SharedStringsTable sst)

throws SAXException {

XMLReader parr = XMLReaderFactory

.createXMLReader("s.parrs.SAXParr");

this.sst = sst;

parr.tContentHandler(this);

return parr;

}

public void startElement(String uri, String localName, String name,

Attributes attributes) throws SAXException {

// c => 单元格

if ("c".equals(name)) {

// 如果下一个元素是 SST 的索引，则将nextIsString标记为true

String cellType = Value("t");

if ("s".equals(cellType)) {

nextIsString = true朋友圈的精美句子;

} el {

nextIsString = fal;

}

//日期格式

String cellDateType = Value("s");

if ("1".equals(cellDateType)){

dateFlag = true;

} el {

dateFlag = fal;

}

String cellNumberType = Value("s");

if("2".equals(cellNumberType)){

numberFlag = true;

} el {

numberFlag = fal;

}

//当元素为t时

if("t".equals(name)){

isTElement = true;

} el {

isTElement = fal;

}

// 置空

lastContents = "";

}

public void endElement(String uri, String localName, String name)

throws SAXException {

// 根据SST的索引值的到单元格的真正要存储的字符串

// 这时characters()方法可能会被调用多次

if (nextIsString) {买二送一

try {

int idx = Integer.parInt(lastContents);

lastContents = new XSSFRichTextString(sst.getEntryAt(idx))

.toString();

} catch (Exception e) {

}

//t元素也包含字符串

if(isTElement){

String value = lastContents.trim();

rowlist.add(curCol, value);

curCol++;

isTElement = fal;

// v => 单元格的值，如果单元格是字符串则v标签的值为该字符串在SST中的索引

// 将单元格内容加入rowlist中，在这之前先去掉字符串前后的空白符

} el if ("v".equals(name)) {

String value = lastContents.trim();

value = value.equals("")?" ":value;

//日期格式处理

if(dateFlag){

Date date = HSSFDateUtil.getJavaDate(Double.valueOf(value));

SimpleDateFormat dateFormat = new SimpleDateFormat(

"dd/MM/yyyy");

value = dateFormat.format(date);

}

//数字类型处理

if(numberFlag){

BigDecimal bd = new BigDecimal(value);

value = bd.tScale(3,BigDecimal.ROUND_UP).toString();

}

rowlist.add(curCol, value);

curCol++;

}el {

//如果标签名称为 row ，这说明已到行尾，调用 optRows() 方法

if (name.equals("row")) {

rowReader.getRows(sheetIndex,curRow,rowlist);

rowlist.clear();

curRow++;

curCol = 0;

}

public void characters(char[] ch, int start, int length)

throws SAXException {

//得到单元格内容的值

lastContents += new String(ch, start, length);

}

Excel2007WriterImpl.java

package l.outofmemory;

public class Excel2007WriterImpl extends AbstractExcel2007Writer {

/**

* @param args

* @throws Exception

*/

public static void main(String[] args) throws Exception {

// TODO Auto-generated method stub

System.out.println("............................");

long start = System.currentTimeMillis();

// 构建excel2007写入器

AbstractExcel2007Writer excel07Writer = new Excel2007WriterImpl();

// 调用处理方法

excel07Writer.process("F://test07.xlsx");

long end = System.currentTimeMillis();

System.out.println("....................." + (end - start) / 1000);

}

/*

* 可根据需求重写此方法，对于单元格的小数或者日期格式，会出现精度问题或者日期格式转化问题，建议使用字符串插入方法

*

* @l.ver2.AbstractExcel2007Writer#generate()

*/

@Override

public void generate() throws Exception {

// 电子表格开始

beginSheet();

for (int rownum = 0; rownum < 100; rownum++) {

// 插入新行

inrtRow(rownum);

// 建立新单元格,索引值从0开始,表示第一列

createCell(0, "中国<" + rownum + "!");

createCell(1, 34343.123456789);

createCell(2, "23.67%");

createCell(3, "12:12:23");

createCell(4, "2010-10-11 12:12:23");

createCell(5, "true");

createCell(6, "fal");

// 结束行

endRow();

}

// 电子表格结束

endSheet();

}

ExcelReaderUtil.java

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