我就不连数据库取数据了，直接本地新建一个List，将List的数据直接导入到Excel表中，连数据库是一个道理，连数据库就是先查询所有数据再导入Excel表中。

新建User代码

package com.qm.entity;

public class User {
	private Integer id;
	private String name;
	private String sex;
	private Integer age;
	
	public User() {
	}
	
	public User(Integer id, String name, String sex, Integer age) {
		super();
		this.id = id;
		this.name = name;
		this.sex = sex;
		this.age = age;
	}
	
	public Integer getId() {
		return id;
	}
	public void setId(Integer id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getSex() {
		return sex;
	}
	public void setSex(String sex) {
		this.sex = sex;
	}
	public Integer getAge() {
		return age;
	}
	public void setAge(Integer age) {
		this.age = age;
	}
	
}

导出数据库的代码

package com.qm.test;

import java.io.File;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import jxl.Workbook;
import jxl.write.Label;
import jxl.write.WritableSheet;
import jxl.write.WritableWorkbook;

import com.qm.entity.User;

public class TestExcel {
	public static void main(String[] args) {
		try {
            WritableWorkbook wwb = null;

            String fileName = "D://user.xls";
            File file=new File(fileName);
            if (!file.exists()) {
                file.createNewFile();
            }

            wwb = Workbook.createWorkbook(file);


            WritableSheet ws = wwb.createSheet("Test Shee 1", 0);
            User u1=new User(1,"全敏","男",18);
            User u2=new User(2,"刘鑫","男",14);
            User u3=new User(3,"奶龙","女",15);
            User u4=new User(4,"刘超","女",11);
            List<User> list= new ArrayList<User>();
            list.add(u1);
            list.add(u2);
            list.add(u3);
            list.add(u4);
            for (User user : list) {
				System.out.println(user.getId()+"="+user.getName()+"="+user.getSex()+"="+user.getAge());
			}
            Label labelId= new Label(0, 0, "编号(id)");
            Label labelName= new Label(1, 0, "姓名(name)");
            Label labelSex= new Label(2, 0, "性别(sex)");
            Label labelAge= new Label(3, 0, "年龄(age)");
            
            ws.addCell(labelId);
            ws.addCell(labelName);
            ws.addCell(labelSex);
            ws.addCell(labelAge);
            for (int i = 0; i < list.size(); i++) {
                Label labelId_i= new Label(0, i+1, list.get(i).getId()+"");
                Label labelName_i= new Label(1, i+1, list.get(i).getName());
                Label labelSex_i= new Label(2, i+1, list.get(i).getSex());
                Label labelAge_i= new Label(3, i+1, list.get(i).getAge()+"");
                ws.addCell(labelId_i);
                ws.addCell(labelName_i);
                ws.addCell(labelSex_i);
                ws.addCell(labelAge_i);
            }
            wwb.write();
            wwb.close();
     } catch (Exception e) {
         e.printStackTrace();
     } 
	}
}

运行。看效果