Java解决Excel导出大批量数据（附上测试代码）
记录一次项目中使用POI导出Excel报错的修改方案。
参考了作者：happyljw的文章 JAVA使用POI如何导出百万级别数据，对代码进行封装扩展。由于项目时间太紧，并未对写的代码进行严格测试，遇到问题的朋友可以一起探讨。
修改结果：100万条数据导出花费58s。比之前效率高多了。
package star;
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.xssf.streaming.SXSSFWorkbook;
import org.junit.Test;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
/**
* @author :[email protected]
* @date :2018年3月2日 下午4:24:53
*/
public class TestExcelImport {
/**
* 测试导出执行器
*
* @param
*/
static class ExcelExportExecutor {
/**
* 工作簿
*/
private SXSSFWorkbook wb = new SXSSFWorkbook(100);
/**
* 表格
*/
private Sheet sheet;
/**
* 原始数据list
*/
private List data;
/**
* 分批次写入数据，分页条数
*/
private int pageSize = 5;
/**
* 当前输出的列
*/
private int currentRow = 0;
/**
* 数据行起始行数
*/
private int dataRowStart = 1;
/**
* 表头
*/
private String[] rowHeader;
/**
* 是否开启row状态监听
*/
private boolean watcherRowStatus;
/**
* 导入row状态监听器
*/
private ExcelExportRowStatusListener rowStatusListener;
ExcelExportExecutor(String[] rowHeader, List data) {
this();
this.rowHeader = rowHeader;
this.data = data;
}
ExcelExportExecutor(String[] rowHeader, List data, DataSheetExecute executorListener) {
this(rowHeader, data);
this.executorListener = executorListener;
}
ExcelExportExecutor(String[] rowHeader
, List data
, DataSheetExecute executorListener
, boolean watcherRowStatus
, ExcelExportRowStatusListener rowStatusListener) {
this(rowHeader, data, executorListener);
this.watcherRowStatus = watcherRowStatus;
this.rowStatusListener = rowStatusListener;
}
ExcelExportExecutor() {
this.sheet = this.wb.createSheet();
}
/**
* 数据切割时的数据设置执行器
*/
private DataSheetExecute executorListener;
public void setExecutorListener(DataSheetExecute executorListener) {
this.executorListener = executorListener;
}
void execute() {
List data = this.data;
/**
* 处理表头
*/
if (this.executorListener == null) {
throw new RuntimeException("未设置执行处理器");
}
/**
* 设置表头
*/
Row row = this.sheet.createRow(this.dataRowStart - 1);
for (int i = 0; i < rowHeader.length; i++) {
row.createCell(i).setCellValue(rowHeader[i]);
}
if (data == null) {
throw new RuntimeException("无效的数据");
}
int size = data.size();
/**
* 导出总条数小于分页条数时，则直接导入，不用分页导入
*/
if (size < pageSize) {
Row tmpRow;
for (int i = 0; i < size; i++) {
tmpRow = sheet.createRow(this.dataRowStart + i);
this.executorListener.execute(tmpRow, data.get(i));
}
data.clear();
} else if (pageSize > 0 && size >= pageSize) {
/*
* 数据总条数
*/
int listSize = data.size();
/*
* 分批次导入数据次数
*/
int batchSize = listSize / pageSize;
/*
* 分批次后，剩余的记录条数
*/
int remain = listSize % pageSize;
List tmp;
for (int i = 0; i < batchSize; i++) {
/*
* 此处快被搞疯了，list.subList(from,to)方法太坑，截取到的是list的视图。
* 如果tmp list在后边clear的话，就会导致data数据丢失，data的长度会逐渐减少pageSize个。
* 导致suList方法会报异常。于是就将代码改为subList(0,pageSize)。
*/
/*
* 将原始list数据按照pageSize分批截取
*/
tmp = data.subList(0, pageSize);
int len = tmp.size();
Row tmpRow;
for (int j = 0; j < len; j++) {
/*
* 记录当前执行到哪一行了
*/
currentRow = i * pageSize + j + 1;
/*
* 创建一个row
*/
tmpRow = sheet.createRow(currentRow);
if (watcherRowStatus && rowStatusListener != null) {
rowStatusListener.listen(tmpRow, currentRow);
}
/*
* 将list中的数据对象设置到指定的row中
*/
this.executorListener.execute(tmpRow, tmp.get(j));
}
/**
* 清除缓存list，优化内存
*/
tmp.clear();
}
if (remain > 0) {
tmp = data.subList(0, remain);
int len = tmp.size();
Row tmpRow;
for (int j = 0; j < len; j++) {
tmpRow = sheet.createRow(currentRow + j + 1);
this.executorListener.execute(tmpRow, tmp.get(j));
}
/**
* 清除缓存list，优化内存
*/
tmp.clear();
}
}
OutputStream outputStream = null;
try {
executorListener.writeExcel(this.wb, outputStream);
} catch (Exception e) {
e.printStackTrace();
} finally {
/*
* 确保自定义保存后忘记调用dispose
*/
if (this.wb != null) {
this.wb.dispose();
}
if (outputStream != null) {
try {
outputStream.close();
} catch (IOException e) {
System.out.println("关闭输出流失败");
}
}
}
}
}
/**
* 数据导出
*
* @param
*/
interface DataSheetExecute {
/**
* 导出数据时，将泛型T设置到row中的每个cell内
*
* @param row 当前row对象
* @param t 泛型T对象
*/
void execute(Row row, T t);
/**
* 输出Excel，自定义实现输出位置（保存到本地，还是上传到其他位置）
*
* @param workbook 生成好的excel文档薄
*/
void writeExcel(SXSSFWorkbook workbook, OutputStream outputStream) throws Exception;
}
/**
* 导入记录条数状态监听，也可以对row对象进行格式化操作。
*/
interface ExcelExportRowStatusListener {
void listen(Row row, int rows);
}
/**
* 测试bean
*/
class PersonUser {
private String name;
private String address;
private String sex;
private String phone;
private String group;
private String id;
private String area;
private String school;
private String stat;
private String score;
public PersonUser(String name, String address, String sex, String phone, String group, String id, String area, String school, String stat, String score) {
this.name = name;
this.address = address;
this.sex = sex;
this.phone = phone;
this.group = group;
this.id = id;
this.area = area;
this.school = school;
this.stat = stat;
this.score = score;
}
public String getPhone() {
return phone;
}
public void setPhone(String phone) {
this.phone = phone;
}
public String getGroup() {
return group;
}
public void setGroup(String group) {
this.group = group;
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getArea() {
return area;
}
public void setArea(String area) {
this.area = area;
}
public String getSchool() {
return school;
}
public void setSchool(String school) {
this.school = school;
}
public String getStat() {
return stat;
}
public void setStat(String stat) {
this.stat = stat;
}
public String getScore() {
return score;
}
public void setScore(String score) {
this.score = score;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
@Override
public String toString() {
return "PersonUser{" +
"name='" + name + '\'' +
", address='" + address + '\'' +
", sex='" + sex + '\'' +
", phone='" + phone + '\'' +
", group='" + group + '\'' +
", id='" + id + '\'' +
", area='" + area + '\'' +
", school='" + school + '\'' +
", stat='" + stat + '\'' +
", score='" + score + '\'' +
'}';
}
}
/**
* 测试导出方法
*/
@Test
public void testExport() {
/*
制造数据
*/
List data = new ArrayList();
for (int i = 0; i < 2000; i++) {
data.add(new PersonUser("金XX:" + i
, "北京市朝阳区:" + i
, "男:" + i
, "137****2152:" + i
, "开发组：" + i
, "" + i + 1
, "华北地区：" + i
, "北京大学：" + i
, "已晋级：" + i
, "1021:" + i));
}
/*
* 文件输出到磁盘的位置
*/
final String filePath = "E:\\3.xlsx";
new ExcelExportExecutor(
new String[]{"姓名", "地址", "性别", "手机号", "组别", "身份证号", "地区", "学校/机构", "晋级状态", "测评成绩"}
, data, new DataSheetExecute() {
public void execute(Row row, PersonUser personUser) {
row.createCell(0).setCellValue(personUser.getName());
row.createCell(1).setCellValue(personUser.getAddress());
row.createCell(2).setCellValue(personUser.getSex());
row.createCell(3).setCellValue(personUser.getPhone());
row.createCell(4).setCellValue(personUser.getGroup());
row.createCell(5).setCellValue(personUser.getId());
row.createCell(6).setCellValue(personUser.getArea());
row.createCell(7).setCellValue(personUser.getSchool());
row.createCell(8).setCellValue(personUser.getStat());
row.createCell(9).setCellValue(personUser.getScore());
}
public void writeExcel(SXSSFWorkbook workbook, OutputStream outputStream) throws Exception {
outputStream = new FileOutputStream(filePath);
workbook.write(outputStream);
}
}, true, new ExcelExportRowStatusListener() {
public void listen(Row row, int rows) {
/*
* 可以对row对象进行设置格式
*/
System.out.println("执行到了：<" + rows + "> 这一行");
}
}).execute();
}
}