apache-poi 实现大数据导出到excel中

package com.test;

import java.io.FileOutputStream;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.streaming.SXSSFWorkbook;
import org.junit.Test;

public class TestPOI {
@Test
public void test() throws InstantiationException, IllegalAccessException, ClassNotFoundException, SQLException, InterruptedException, IOException {
String xlsFile = "D:/testPOI.xlsx";                 //输出文件
Workbook wb = new SXSSFWorkbook(100);
Sheet sheet = wb.createSheet("我的第一个工作簿");       //建立新的sheet对象

Row nRow = null;
Cell nCell   = null;

Class.forName("com.mysql.jdbc.Driver").newInstance();
String url = "jdbc:mysql://localhost:3306/ssh?characterEncoding=UTF-8";
String user = "root";
String password = "123456";

Connection conn = DriverManager.getConnection(url, user,password);
Statement stmt = conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);

String sql = "select * from user limit 65536";
sql = "select * from user";

long  startTime = System.currentTimeMillis();   //开始时间
System.out.println("strat execute time: " + new java.util.Date());

//实际调用时要分次读取，否则记录过多。目前可以支持到百万，但读取耗时，占用大量内存
ResultSet rs = stmt.executeQuery(sql);
long readDataTime = System.currentTimeMillis(); //准备数据时间
System.out.println("read data execute  time: " + (readDataTime - startTime)/1000 + "m");

//context
int rowNo = 0;
int colNo = 0;
//创建一行
nRow = sheet.createRow(rowNo++);
//创建一行的第一列
nCell = nRow.createCell(colNo++);
nCell.setCellValue("id");
//创建一行的第二列
nCell = nRow.createCell(colNo++);
nCell.setCellValue("name");
//创建一行的第三列
nCell = nRow.createCell(colNo++);
nCell.setCellValue("pass");
while(rs.next()) {
colNo = 0;
nRow = sheet.createRow(rowNo++);

nCell = nRow.createCell(colNo++);
nCell.setCellValue(rs.getString(colNo));

nCell = nRow.createCell(colNo++);
nCell.setCellValue(rs.getString(colNo));

nCell = nRow.createCell(colNo++);
nCell.setCellValue(rs.getString(colNo));

if(rowNo%100==0){           //每100行输出日志
System.out.println("row no: " + rowNo);
}

Thread.sleep(1);            //休息一下，防止对CPU占用
}

long finishedTime = System.currentTimeMillis(); //处理完成时间
System.out.println("finished execute  time: " + (finishedTime - startTime)/1000 + "m");

FileOutputStream fOut = new FileOutputStream(xlsFile);
wb.write(fOut);
fOut.flush();
fOut.close();

long stopTime = System.currentTimeMillis();     //写文件时间
System.out.println("write xls file time: " + (stopTime - startTime)/1000 + "m");

rs.close();
stmt.close();
conn.close();
}
}

<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml</artifactId>
<version>3.9</version>
</dependency>