poi 学习之使用 Apche poi 读取数据库中的数据并写入Excel

Apchepoi读取数据库中的数据并写入 Excel

 

之前写了一篇poi读写excel的简单demo，但考虑到实际项目中，主要还是对将数据库中的数据进行写入excel，所以练习了一个也是比较简单的demo。

 

首先：

 

数据库：

 

创建一个数据库连接的Util类

 

DBConnectionUtil.java

 

package com.poi.org;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class DBConnectionUtil {
	private static Connection conn = null;
	private static String Driver = "com.mysql.jdbc.Driver";
	private static String url = "jdbc:mysql://localhost/quechao?useUnicode=true&characterEncoding=utf8";
	private static String userName = "root";
	private static String password = "123456";
	
	public static Connection getConnection(){
		try {
			Class.forName(Driver);
			conn = DriverManager.getConnection(url, userName, password);
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		}
		catch (SQLException e) {
			e.printStackTrace();
		}
		return conn;
	}
	public static void closeDB(ResultSet rs, Statement st, Connection conn){
		try {
			if(rs != null) rs.close(); rs = null;
			if(st != null) st.close(); st = null;
			if(conn != null) conn.close(); conn = null;
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
}

 

实体类 Hospital.java

 

package com.poi.model;

public class Hospital {
	private Integer id;

    private String hospitalOn;

    private String province;

    private String city;

    private String title;

	public Integer getId() {
		return id;
	}

	public void setId(Integer id) {
		this.id = id;
	}

	public String getHospitalOn() {
		return hospitalOn;
	}

	public void setHospitalOn(String hospitalOn) {
		this.hospitalOn = hospitalOn;
	}

	public String getProvince() {
		return province;
	}

	public void setProvince(String province) {
		this.province = province;
	}

	public String getCity() {
		return city;
	}

	public void setCity(String city) {
		this.city = city;
	}

	public String getTitle() {
		return title;
	}

	public void setTitle(String title) {
		this.title = title;
	}
}

 

测试类QueryHospital.java

 

package com.poi.test;

import java.io.File;
import java.io.FileOutputStream;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;

import com.poi.model.Hospital;
import com.poi.org.DBConnectionUtil;

public class QueryHospital {
	public static List<Hospital> selectHospital()throws Exception{
		Connection conn = null;
		ResultSet rs = null;
		Statement st = null;
		String sql = "select * from hospital";
		conn = DBConnectionUtil.getConnection();
		List<Hospital> list = new ArrayList<Hospital>();
		try {
			st = conn.createStatement();
			rs = st.executeQuery(sql);
			
			while(rs.next()){
				Hospital hospital = new Hospital();
				//hospital.setId(rs.getInt("id"));
				hospital.setId(rs.getInt(1));
				//hospital.setHospitalOn(String.valueOf(rs.getInt("hospitalOn")));
				hospital.setHospitalOn(rs.getString(2));
				hospital.setProvince(rs.getString(3));
				hospital.setCity(rs.getString(4));
				//hospital.setTitle(String.valueOf(rs.getInt("title")));
				hospital.setTitle(rs.getString(5));
				
				list.add(hospital);
			}
		} catch (Exception e) {
			e.printStackTrace();
		}finally{
			DBConnectionUtil.closeDB(rs, st, conn);
		}
		return list;
	}
	public void createExcel()throws Exception{
		HSSFWorkbook workBook = new HSSFWorkbook();
		HSSFSheet sheet = workBook.createSheet("第一页");
		sheet.setColumnWidth(0, 2500);
		sheet.setColumnWidth(1, 5000);
		HSSFRow row = sheet.createRow(0);
		HSSFCell cell[] = new HSSFCell[5];
		for(int i = 0; i < 5; i++){
			cell[i] = row.createCell(i);
		}
		cell[0].setCellValue("id");
		cell[1].setCellValue("hospitalOn");
		cell[2].setCellValue("province");
		cell[3].setCellValue("city");
		cell[4].setCellValue("title");
		
		List<Hospital> list = QueryHospital.selectHospital();
		if(list != null && list.size() > 0){
			for(int i = 0; i < list.size(); i++){
				Hospital hospital = list.get(i);
				HSSFRow dataRow = sheet.createRow(i+1);
				HSSFCell dataCell[] = new HSSFCell[5];
				for(int j = 0; j < 5; j++){
					dataCell[j] = dataRow.createCell(j);
				}
				dataCell[0].setCellValue(hospital.getId());
				dataCell[1].setCellValue(hospital.getHospitalOn());
				dataCell[2].setCellValue(hospital.getProvince());
				dataCell[3].setCellValue(hospital.getCity());
				dataCell[4].setCellValue(hospital.getTitle());
				
				File file = new File("E:\\hospital.xls");
				FileOutputStream fos = new FileOutputStream(file);
				workBook.write(fos);
				fos.close();
			}
		}
	}
	public static void main(String[] args)throws Exception {
		QueryHospital queryHospital = new QueryHospital();
		queryHospital.createExcel();
	}
}

考虑到每个人项目中用的持久层技术（Hibernate、Mybatis等）会有不同，所以这里用的jdbc，后续抽时间会再写一个读取Excel并写入数据库demo。

 

注：以上所写部分来自网络以及自己学习时所记录，若有高人指点，必虚心学习。

 

原文地址：http://blog.csdn.net/u014011236/article/details/39204591