poi导出excel

1:需要的jar

百度云： https://pan.baidu.com/s/1TP9YWhTQu8QHpB41AU3I5Q 提取码: ymtj 

               去掉ooxml-schemas-1.3.jar，不去也不影响

  maven：

<dependency>
      <groupId>org.apache.poi</groupId>
      <artifactId>poi</artifactId>
      <version>3.17</version>
    </dependency>
    <dependency>
      <groupId>org.apache.poi</groupId>
      <artifactId>poi-ooxml</artifactId>
      <version>3.17</version>
    </dependency>

2：创建三个类，一个实体类 ，一个excel实体类，一个测试类， 创建Java工程，引入夹包，直接把代码粘过去，运行测试类的main方法，看d盘生成的文件

//*************************************实体类的写法开始*************************************

package com;

public class Test1 {
    private String test1;
    private Integer test2;
    private String test3;
    private Long test4;
    private String test5;
    private String test6;
    private Integer test7;
    private String test8;
    private Integer test9;
    private String test10;
    
    public Test1(String test1, Integer test2, String test3, Long test4,
            String test5, String test6, Integer test7, String test8,
            Integer test9, String test10) {
        super();
        this.test1 = test1;
        this.test2 = test2;
        this.test3 = test3;
        this.test4 = test4;
        this.test5 = test5;
        this.test6 = test6;
        this.test7 = test7;
        this.test8 = test8;
        this.test9 = test9;
        this.test10 = test10;
    }
    public String getTest1() {
        return test1;
    }
    public void setTest1(String test1) {
        this.test1 = test1;
    }
    public Integer getTest2() {
        return test2;
    }
    public void setTest2(Integer test2) {
        this.test2 = test2;
    }
    public String getTest3() {
        return test3;
    }
    public void setTest3(String test3) {
        this.test3 = test3;
    }
    public Long getTest4() {
        return test4;
    }
    public void setTest4(Long test4) {
        this.test4 = test4;
    }
    public String getTest5() {
        return test5;
    }
    public void setTest5(String test5) {
        this.test5 = test5;
    }
    public String getTest6() {
        return test6;
    }
    public void setTest6(String test6) {
        this.test6 = test6;
    }
    public Integer getTest7() {
        return test7;
    }
    public void setTest7(Integer test7) {
        this.test7 = test7;
    }
    public String getTest8() {
        return test8;
    }
    public void setTest8(String test8) {
        this.test8 = test8;
    }
    public Integer getTest9() {
        return test9;
    }
    public void setTest9(Integer test9) {
        this.test9 = test9;
    }
    public String getTest10() {
        return test10;
    }
    public void setTest10(String test10) {
        this.test10 = test10;
    }
}

//*************************************实体类的写法结束*************************************

//*************************************excel实体类的写法开始*************************************

package com;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Method;
import java.util.Iterator;
import java.util.List;
import org.apache.poi.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

public class TestExcel<T> {
    
     //工作表sheet名称,可以为空
    private String sheetName;
    //导出的excel名称
    private String fileName;
    //sheet各个列的表头
    private String[] headList;
    //各个列的key值--对应实体字段名
    private String[] headKey;
    //sheet需要填充的数据信息
    private List<T> data;

    public TestExcel(){

    }
    public TestExcel(String sheetName,String[] headList,String[] headKey,List<T> data){
        this.sheetName = sheetName;
        this.headList = headList;
        this.headKey = headKey;
        this.data = data;
    }

    public String getFileName() {
        return fileName;
    }

    public void setFileName(String fileName) {
        this.fileName = fileName;
    }

    public String[] getHeadList() {
        return headList;
    }

    public void setHeadList(String[] headList) {
        this.headList = headList;
    }

    public String[] getHeadKey() {
        return headKey;
    }

    public void setHeadKey(String[] headKey) {
        this.headKey = headKey;
    }

    public List<T> getData() {
        return data;
    }

    public void setData(List<T> data) {
        this.data = data;
    }


    public String getSheetName() {
        return sheetName;
    }

    public void setSheetName(String sheetName) {
        this.sheetName = sheetName;
    }

    //生成 XSSFWorkbook
    public XSSFWorkbook exportExcel() {
        
        if (this.headList == null || this.headList.length == 0) {
            System.out.println("没有表头对应数据");
            return null;
        }
        if (this.headKey == null || this.headKey.length == 0) {
            System.out.println("没有表头对应字段数据");
            return null;
        }
        if (this.headList.length != this.headKey.length) {
            System.out.println("表头和对应的key长度不一致");
            return null;
        }
        if (this.data == null || this.data.isEmpty()) {
            System.out.println("没有要导出的数据");
            return null;
        }

        //表头行有多少列
        int titleLength = 0;
        // 声明一个工作薄
        XSSFWorkbook workbook = new XSSFWorkbook();
        // 生成一个表格
        XSSFSheet sheet = null;
        if (this.sheetName != null && !"".equals(this.sheetName)) {
            sheet = workbook.createSheet(this.sheetName);
        } else {
            sheet = workbook.createSheet();
        }

        //创建excel的表头数据
        titleLength = this.headList.length;
        XSSFRow titleRow = sheet.createRow(0);
        for (int i = 0; i < this.headList.length; i++) {
            XSSFCell cell = titleRow.createCell(i);
            cell.setCellValue(this.headList[i]);
        }

// CellRangeAddress 对象的构造方法需要传入合并单元格的首行、最后一行、首列、最后一列。
//CellRangeAddress cra = new CellRangeAddress(0, 0, 0, heardName.length - 1);

        //遍历数据
        Iterator<T> it = this.data.iterator();
        int dateRows = 0;
        while (it.hasNext()) {
            XSSFRow dataRow = sheet.createRow(++dateRows);
            T t = (T) it.next();//获取Java对象
            for(int i=0;i<titleLength;i++){
                String fieldKeyName = this.headKey[i];//循环获取Java实体变量名
                Object  value =null;
                try {
                    PropertyDescriptor pd = new PropertyDescriptor(fieldKeyName, t.getClass());//获取t 对象中指定变量的get方法值
                    Method m = pd.getReadMethod();
                    value = m.invoke(t, new Object[] {});//获取指定变量对应的get方法的值
                }catch (Exception ex) {
                    ex.printStackTrace();
                }
                XSSFCell dataCell = dataRow.createCell(i);
                dataCell.setCellValue(value==null?"":value.toString());
            }
        }
        return workbook;
    }
}

//*************************************excel实体类的写法结束*************************************

//*************************************测试类的写法开始*************************************

package com;

import java.io.FileOutputStream;
import java.util.ArrayList;
import java.util.List;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

public class Test {
    public static void main(String[] args) {
        String[] headList={"表头1","表头2","表头3","表头4","表头5","表头6","表头7","表头8","表头9","表头10"};
        String[] headKey={"test1","test2","test3","test4","test5","test6","test7","test8","test9","test10"};
        String filename = "导出excel表格";
        TestExcel<Test1> ex = new TestExcel<Test1>(null,headList,headKey,dataList());
        try {
            XSSFWorkbook workbook = ex.exportExcel();
            FileOutputStream out = new FileOutputStream("d:\部门通讯录.xlsx");
            workbook.write(out);
            out.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
        System.out.println("导出成功!!!!!!!!");
    }
    public static List<Test1> dataList() {
        List<Test1> list = new ArrayList<Test1>();
        for(int i=0;i<20;i++){
            Test1 t1 = new Test1("1",2,"3",4l,"5","6",3,"7",3,"8");
            list.add(t1);
        }
        return list;
    }
}

//*************************************测试类的写法结束*************************************

3：运行结果

4:在web项目中controller中的大概写法，这样前端直接调用这个方法，就会在页面上直接下载了

//**********************************开始****************************************

public String exportWord(HttpServletRequest request, HttpServletResponse response) {
        String[] headList={"表头1","表头2","表头3","表头4","表头5","表头6","表头7","表头8","表头9","表头10"};//表头
        String[] headKey={"test1","test2","test3","test4","test5","test6","test7","test8","test9","test10"};//对应的实体类字段,可以是部分字段
        String filename = "部门信息";
        List<Test1> list = testServiceImpl.selectList();//获取数据,一般是从库里查询的数据，这里可以改成自己造的数据
        ExcelExport<Test1> ex = new ExcelExport<Test1>(null,headList,headKey,list);
        XSSFWorkbook workbook= ex.exportExcel();
       
        try {
            response.setHeader("Content-Disposition","attachment;filename="+new String(filename.getBytes(), "iso8859-1")+".xlsx");
            OutputStream out = response.getOutputStream();
            workbook.write(out);
            out.close();
        } catch (IOException e) {
            return "导出数据异常！！！";
        }
        return null;
    }

//**********************************结束***************************************