Servlet實現匯出下載csv檔案

工作上遇到的場景，需要將客戶列表資料匯出成csv檔案。測試了一個最簡單版本，記錄一下。

訂單實體類：

package entity;

/**
 * 訂單資訊實體
 * Created by dylan-pc on 2017/8/17.
 */
public class Order {
    private String orderNo;
    private String orderStatus;
    private String orderDt;
    private String productName;
    private double price;

    public Order(String orderNo, String orderStatus, String orderDt, String productName, double price) {
        this.orderNo = orderNo;
        this.orderStatus = orderStatus;
        this.orderDt = orderDt;
        this.productName = productName;
        this.price = price;
    }

    public String getOrderNo() {
        return orderNo;
    }

    public void setOrderNo(String orderNo) {
        this.orderNo = orderNo;
    }

    public String getOrderStatus() {
        return orderStatus;
    }

    public void setOrderStatus(String orderStatus) {
        this.orderStatus = orderStatus;
    }

    public String getOrderDt() {
        return orderDt;
    }

    public void setOrderDt(String orderDt) {
        this.orderDt = orderDt;
    }

    public String getProductName() {
        return productName;
    }

    public void setProductName(String productName) {
        this.productName = productName;
    }

    public double getPrice() {
        return price;
    }

    public void setPrice(double price) {
        this.price = price;
    }
}

匯出訂單Servlet

package servlet;

import entity.Order;
import util.CSVUtils;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.URLEncoder;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Date;
import java.util.List;

/**
 * Created by dylan-pc on 2017/8/26.
 */
@WebServlet(name = "exportOrderServlet", urlPatterns = {"/exportOrder"})
public class exportOrderServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doGet(request, response);
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        //設定response
        response.setContentType("application/x-download;charset=utf-8");
        //生成樣例資料

        List<Order> orders = Arrays.asList(new Order("sa20170826001", "shipping", "2017/8/26", "羅西尼女表", 499),
                new Order("sa20170826002", "submit", "2017/8/26", "耐克籃球鞋", 1099),
                new Order("sa20170826001", "finish", "2017/8/26", "新百倫G500慢跑鞋", 234));

        //設定檔名
        SimpleDateFormat dtf = new SimpleDateFormat("yyyyMMddHHmmssSSS");
        String curDateStr = dtf.format(new Date());
        String fileName = "訂單列表-" + curDateStr + ".csv";
        fileName = URLEncoder.encode(fileName, "UTF-8");
        response.addHeader("Content-Disposition", "attachment;filename=" + fileName);

        //獲得列印流
        PrintWriter pw = response.getWriter();
        pw.println("訂單號, 訂單狀態, 下單日期,商品名稱,商品價格");

        StringBuilder sb = new StringBuilder();
        for (Order o : orders) {
            sb.append(o.getOrderNo() + "," + o.getOrderStatus() + "," + o.getOrderDt() + "," + o.getProductName() + "," + Double.toString(o.getPrice()) + "\n");
        }

        pw.print(sb);
        pw.close();

    }
}

實現效果：