使用线程池导出Excel数据

之前同事在做一个功能的时候，需要导出一些数据，但是组装数据量的过程比较麻烦一点，所以这里给了一个建议
看看能不能使用多线程的方法来进行处理。顺便写了两个demo，一种方式是批量分段去往一个sheet页中写入数
据，另一种方式是往多个sheet也中写入数据。demo如下：

批量分段导出数据

package com.zkn.newlearn.opensource.poi;
/**
* Created by zkn on 2017/11/15.
*/

import com.google.common.util.concurrent.ThreadFactoryBuilder;
import org.apache.poi.hssf.usermodel.*;
import org.apache.poi.ss.usermodel.CellStyle;

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.concurrent.*;

/**
* @author zkn
* @date 2017/11/15 23:34
*/
public class CreateMultipleSheet {

public static void main(String[] args) {
//处理器核心数
int processor = Runtime.getRuntime().availableProcessors();
//HSSFWorkbook 一个sheet页只能写入六万多条数据
HSSFWorkbook workBook = new HSSFWorkbook();
//创建格式
CellStyle style = workBook.createCellStyle();
//居中格式
style.setAlignment(HSSFCellStyle.ALIGN_CENTER);
//创建sheet页
HSSFSheet sheet = workBook.createSheet();
//创建一行
HSSFRow hssfRow = sheet.createRow(0);
HSSFCell hssfCell = hssfRow.createCell(0);
hssfCell.setCellStyle(style);
hssfCell.setCellValue("第" + 1 + "个sheet页，第一行，第一个单元格");

hssfCell = hssfRow.createCell(1);
hssfCell.setCellStyle(style);
hssfCell.setCellValue("第" + 1 + "个sheet页，第一行，第二个单元格");

hssfCell = hssfRow.createCell(2);
hssfCell.setCellStyle(style);
hssfCell.setCellValue("第" + 1 + "个sheet页，第一行，第三个单元格");

//手工创建线程池
ExecutorService executorService = new ThreadPoolExecutor(processor, processor, 1000, TimeUnit.MILLISECONDS, new LinkedBlockingDeque(),
new ThreadFactoryBuilder().setNameFormat("poi-task-%d").build());
//计数器 等待线程池中的线程执行完毕
CountDownLatch countDownLatch = new CountDownLatch(processor);
for (int i = 1; i <= processor; i++) {
int start = (i - 1) * 100 + 1;
int end = i * 100;
//放入线程池中
executorService.execute(() -> createRows(sheet, start, end, countDownLatch));
}
try {
//等待所有线程执行完毕
countDownLatch.await();
//关闭线程池
executorService.shutdown();
} catch (InterruptedException e) {
e.printStackTrace();
}
FileOutputStream fou = null;
try {
fou = new FileOutputStream("D:\\LearnVideo\\multiSheet.xls");
workBook.write(fou);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (fou != null) {
try {
fou.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}

private static void createRows(HSSFSheet hSSFSheet, int startRow, int endRow, CountDownLatch countDownLatch) {
HSSFRow hssfRows;
HSSFCell hSSFCells;
int i = startRow;
try {
while (i <= endRow) {
hssfRows = getRows(hSSFSheet, i);
hSSFCells = hssfRows.createCell(0);
hSSFCells.setCellValue("第" + (i + 1) + "行，第一个单元格");

hSSFCells = hssfRows.createCell(1);
hSSFCells.setCellValue("第" + (i + 1) + "行，第一个单元格");

hSSFCells = hssfRows.createCell(2);
hSSFCells.setCellValue("第" + (i + 1) + "行，第一个单元格");
++i;
}
} finally {
countDownLatch.countDown();
}
}

/**
* 创建表格 这里要加锁
*
* @param hSSFSheet
* @param row
* @return
*/
private static HSSFRow getRows(HSSFSheet hSSFSheet, int row) {
synchronized (Object.class) {
return hSSFSheet.createRow(row);
}
}
}

向多个sheet页中写入数据

package com.zkn.newlearn.opensource.poi;

import com.google.common.util.concurrent.ThreadFactoryBuilder;
import org.apache.poi.hssf.usermodel.*;
import org.apache.poi.ss.usermodel.CellStyle;
import org.apache.poi.xssf.streaming.SXSSFCell;
import org.apache.poi.xssf.streaming.SXSSFRow;
import org.apache.poi.xssf.streaming.SXSSFSheet;
import org.apache.poi.xssf.streaming.SXSSFWorkbook;

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.concurrent.*;

/**
* @author zkn
* @date 2017/11/15 23:34
*/
public class CreateMultipleSheetNew {

private final static Object object = new Object();

public static void main(String[] args) {
//处理器核心数
int processor = Runtime.getRuntime().availableProcessors();
//XSSFWorkbook 一次只能写入六万多条数据，所以这里最好使用SXSSFWorkbook
SXSSFWorkbook workBook = new SXSSFWorkbook();
//创建格式
CellStyle style = workBook.createCellStyle();
//居中格式
style.setAlignment(HSSFCellStyle.ALIGN_CENTER);
//手工创建线程池
ExecutorService executorService = new ThreadPoolExecutor(processor, processor, 1000, TimeUnit.MILLISECONDS, new LinkedBlockingDeque(),
new ThreadFactoryBuilder().setNameFormat("poi-task-%d").build());
//计数器 等待线程池中的线程执行完毕
CountDownLatch countDownLatch = new CountDownLatch(processor);
for (int i = 0; i < processor; i++) {
int sheetId = i;
//放入线程池中
executorService.execute(() -> createSheet(workBook, style, sheetId, countDownLatch));
}
try {
//等待所有线程执行完毕
countDownLatch.await();
executorService.shutdown();
} catch (InterruptedException e) {
e.printStackTrace();
}
FileOutputStream fou = null;
try {
fou = new FileOutputStream("D:\\LearnVideo\\multiSheetNew.xls");
workBook.write(fou);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (fou != null) {
try {
fou.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}

private static void createSheet(SXSSFWorkbook workBook, CellStyle style, int sheetId, CountDownLatch countDownLatch) {
try {
SXSSFSheet hSSFSheet;
//这个地方一定要加锁，要不然会出现问题
synchronized (object) {
//创建sheet页
hSSFSheet = workBook.createSheet(String.format("第%d个sheet页", sheetId));
}
//创建一行
SXSSFRow hssfRow = hSSFSheet.createRow(0);
SXSSFCell hssfCell = hssfRow.createCell(0);
hssfCell.setCellStyle(style);
hssfCell.setCellValue("第" + sheetId + "个sheet页，第一行，第一个单元格");

hssfCell = hssfRow.createCell(1);
hssfCell.setCellStyle(style);
hssfCell.setCellValue("第" + sheetId + "个sheet页，第一行，第二个单元格");

hssfCell = hssfRow.createCell(2);
hssfCell.setCellStyle(style);
hssfCell.setCellValue("第" + sheetId + "个sheet页，第一行，第三个单元格");
SXSSFRow hssfRows;
SXSSFCell hSSFCells;
for (int i = 1; i < 3; i++) {
hssfRows = hSSFSheet.createRow(i);
hSSFCells = hssfRows.createCell(0);
hSSFCells.setCellStyle(style);
hSSFCells.setCellValue("第" + sheetId + "个sheet页，第" + (i + 1) + "行，第一个单元格");

hSSFCells = hssfRows.createCell(1);
hSSFCells.setCellStyle(style);
hSSFCells.setCellValue("第" + sheetId + "个sheet页，第一个单元格");

hSSFCells = hssfRows.createCell(2);
hSSFCells.setCellStyle(style);
hSSFCells.setCellValue("第" + sheetId + "个sheet页，第一个单元格");
}
} finally {
//计数器减一
countDownLatch.countDown();
}
}
}