分层开发之DTO和JXL读取excel写入excel

Posted 2021-01-21 zwz-bk

　　什么是DTO，为什么要DTO？
　　数据传输对象，简单的来说就是用户在数据库的操作中涉及到了多表的属性，pojo中单独的类不能作为传输对象。因为他只对应了操作中的一部分属性，比如有学生表（姓名，学号，班级号）班级表（班级号，班级名）。当你查询某学生的班级名时，单独的学生类和班级类都不足以代表他们。因此就需要我们的dto，dto当你需要什么属性你就定义什么属性，仅作为一个传输对象。

　　JXL的用法workbook

　　可写表格与只读表格

　　读取exce

import java.io.File;

import jxl.Cell;
import jxl.Hyperlink;
import jxl.Sheet;
import jxl.Workbook;
/**
 * 读取excel
 * @author Administrator
 *
 */
public class Test {
    public static void main(String[] args) throws Exception {
        Workbook book = Workbook.getWorkbook(new File("aa.xls"));
        Sheet sheet = book.getSheet("first");
        int rows = sheet.getRows();
        int cols = sheet.getColumns();
        for (int i = 0; i < rows; i++) {
            for (int j = 0; j < cols; j++) {
                System.out.print(sheet.getCell(j, i).getContents()+"	");
            }
            System.out.println();
        }
        Cell cell = sheet.getCell(0, 0);
        Hyperlink[] links = sheet.getHyperlinks();
        System.out.println(links.length);
        for (int i = 0; i < links.length; i++) {
            System.out.println(links[i].getURL().toString());
        }
    }

}

　　写入excel

package cn.zkingsoft;

import java.io.File;
import java.net.URL;

import jxl.Workbook;
import jxl.write.Label;
import jxl.write.Number;
import jxl.write.WritableHyperlink;
import jxl.write.WritableImage;
import jxl.write.WritableSheet;
import jxl.write.WritableWorkbook;

/**
 * 写入excel
 * @author Administrator
 *
 */
public class Test2 {
	public static void main(String[] args)  throws Exception{
		WritableWorkbook book = Workbook.createWorkbook(new File("classmate.xls"));
		WritableSheet sheet  = book.createSheet("0913A", 0);
		sheet.addCell(new Label(0,0,"黄传名"));
		sheet.addCell(new Label(0,1,"45.89"));
		sheet.addCell(new Number(1,1,45.89d));
		sheet.addImage(new WritableImage(2,2,5,10,new File("_logo_8.png")));
		sheet.addHyperlink(new WritableHyperlink(0,3,new URL("https://www.baidu.com")));
		book.write();
		book.close();
	}

}