java easyreport 导入excel、 txt 数据批量读取（五）

有时候我们需要读的报表数据很大，这时候一次加载所有数据有可能会出现内存溢出，所以我们需要采用批量读取来实现。

导入测试demo

package example;

import java.io.File;

import java.io.FileInputStream;

import java.util.List;

import java.util.Map;

import model.Student;

import test.AbstractExcelTest;

import com.easyReport.read.temp.PropertyTemp;

import com.easyReport.read.temp.ReadTemp;

public class TestExcelBatch extends AbstractExcelTest<Student> {

@Override

public void test() {

FileInputStream fileInputStream;

try {

fileInputStream = new FileInputStream(new File("testFile/test5.xls"));

testReadBean(fileInputStream);

// testReadMap(fileInputStream);

fileInputStream.close();

} catch (Exception e) {

e.printStackTrace();

}

}

@Override

protected ReadTemp bulidReadTemp() {

//模板设置批次构造方法，一次读取10行

ReadTemp readTemp = new ReadTemp(1,10);

readTemp.addPropertyTemp(new PropertyTemp("姓名", "name"));

readTemp.addPropertyTemp(new PropertyTemp("年龄", "age"));

readTemp.addPropertyTemp(new PropertyTemp("科目", "course.name"));

readTemp.addPropertyTemp(new PropertyTemp("分数", "course.score"));

return readTemp;

}

@Override

protected void writeBeanList(List<Student> modelLists) {

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

for (Student s : modelLists) {

System.out.println(s.getName() + "|"

+ s.getAge()+s.getCourse().getName()+"|"+s.getCourse().getScore());

}

}

@Override

protected void writeMapList(List<Map<String, Object>> mapLists) {

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

for (Map<String, Object> m : mapLists) {

System.out.println(m.get("name") + "|" + m.get("age")+"|" + m.get("course.name")+"|" + m.get("course.score"));

}

}

}

基类basicTest

public void testReadBean(FileInputStream fis) throws Exception {

ConvertReader reader = buildReader();

//判断是否批次读取，若批次读取，写每批次数据

if(reader.getContext().getTemp().getBatch() == 0){

writeBeanList((List<T>) reader.readToBeanList(fis, getModelClass()));

}else{

//判断是否批次读取完成

while(!reader.isEnd()){

writeBeanList((List<T>) reader.readToBeanList(fis, getModelClass()));

}

}

}

public void testReadMap(FileInputStream fis) throws Exception {

ConvertReader reader = buildReader();

writeMapList(reader.readToMapList(fis));

if(reader.getContext().getTemp().getBatch() == 0){

writeMapList(reader.readToMapList(fis));

}else{

while(!reader.isEnd()){

writeMapList(reader.readToMapList(fis));

}

}

}

执行demo测试类，运行结果：

--------------bean---------------

王老五|12语文|80.0

柯景腾|13语文|78.0

沈佳宜|14语文|88.0

王小贱|15语文|60.0

黄小仙|12语文|54.0

李大仁|14语文|76.0

程又青|13语文|58.0

陈寻|12语文|67.0

方茴|12语文|87.0

沈晓棠|13语文|89.0

--------------bean---------------

林嘉茉|14语文|68.0

赵烨|14语文|50.0

苏凯|12语文|78.0

乔燃|13语文|90.0