A. java将sql数据导出到excel中
如果运行的时候报以下的错误：
java.lang.NullPointerException
java.lang.NullPointerException
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:164)
at test.<init>(test.java:42)
at test.main(test.java:64)
就表示你定义的变量String sql_driver 没有赋值。
如果数据库是Mysql，则数据库驱动变量的值应该是：
String sql_driver="com.mysql.jdbc.Driver";
B. java将SQL检索结果导出excel文件
你查询语句的时候执行以下数据库的to_char函数转成字符串不就可以了。
C. 如何用JAVA将数据库中的数据导入到excel表格
import java.io.*;
import java.text.SimpleDateFormat;
import java.util.*;
import java.sql.*;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import jxl.*;
public class SimUpdate {
private String fileName;
public ZfzSimUpdate(String fileName){
this.fileName = fileName;
}
static Map tNames;
static{
tNames = new HashMap();
}
/**
* 用于产生 数据库的 ID 值，组成 [年月日时分秒(100-999)] 总共 17 位数.
* 根据不同的表名，可保证同一秒内产生的 ID 号不重复
*/
private static String getDtime() {
String rid;
Date nd = new Date();
SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
rid = sdf.format(nd);
return rid;
}
public String getSeqNumber(String tableName) {
if(tableName == null || "".equals(tableName))
tableName = "GENERY";
Integer it;
// noinspection SynchronizeOnNonFinalField
synchronized(tNames){
it = (Integer)tNames.get(tableName);
if(it == null){
it = new Integer(100);
tNames.put(tableName, it);
}else{
if(it.intValue() > 998)
it = new Integer(100);
else
it = new Integer(1 + it.intValue());
tNames.put(tableName, it);
}
}
return getDtime() + String.valueOf(it);
}
private void updateDb(){
try{
Connection conn = DbPool.connectDB();
if(conn != null){
Statement stmt = conn.createStatement();
/**********************************************/
jxl.Workbook rwb = null;
try{
//构建Workbook对象 只读Workbook对象
//直接从本地文件创建Workbook
//从输入流创建Workbook
InputStream is = new FileInputStream(fileName);
rwb = Workbook.getWorkbook(is);
//Sheet(术语：工作表)就是Excel表格左下角的Sheet1,Sheet2,Sheet3但在程序中
//Sheet的下标是从0开始的
//获取第一张Sheet表
Sheet rs = rwb.getSheet(0);
//获取Sheet表中所包含的总列数
int rsColumns = rs.getColumns();
//获取Sheet表中所包含的总行数
int rsRows = rs.getRows();
//获取指这下单元格的对象引用
String simNumber = "",termSeqId = "";
//指定SIM卡号及序列号
for(int i=0;i<rsRows;i++){
for(int j=0;j<rsColumns;j++){
Cell cell = rs.getCell(j,i);
if(j==0){
simNumber = cell.getContents();
}
termSeqId = "633"+simNumber;
}
String sql = "查询SQL";
int isOk = stmt.executeUpdate(sql);
if(isOk == 0 && !simNumber.equals("")){
String termId = getSeqNumber("termInf");
String insertSql = "自定义INSERT";
int isAdd = stmt.executeUpdate(insertSql);
if(isAdd > 0){
System.out.println("成功插入第"+i+"条数据");
}
}
//System.out.println("SIM卡号:"+simNumber+",序列号:"+termSeqId);
}
//以下代码为写入新的EXCEL,这里不使用,所以注释
/*
//利用已经创建的Excel工作薄创建新的可写入的Excel工作薄
jxl.write.WritableWorkbook wwb = Workbook.createWorkbook(new File("D://Book2.xls"),rwb);
//读取第一张工作表
jxl.write.WritableSheet ws = wwb.getSheet(0);
//获取第一个单元格对象
jxl.write.WritableCell wc = ws.getWritableCell(0, 0);
//决断单元格的类型，做出相应的转化
if (wc.getType() == CellType.LABEL) {
Label l = (Label) wc;
l.setString("The value has been modified.");
}
//写入Excel对象
wwb.write();
wwb.close();
*/
}catch(Exception e){
e.printStackTrace();
}
finally{
//操作完成时，关闭对象，翻译占用的内存空间
rwb.close();
}
/*********************************************/
}
}catch(Exception e){
e.printStackTrace();
}
}
public static void main(String args[]){
DbPool dbPool = new DbPool("dbConn.cfg");//连接数据库
SimUpdate simUpdate = new SimUpdate("zfz_sim.xls");
simUpdate.updateDb();
}
}
我只用了读取XLS,写入没试,应该没问题吧,你把注释了的拿 来试一下吧
D. java中把SQL数据库中的表导出到excel中.怎么实现
前段时间正好做了，导入和导出的，你自己看吧
/**导出数据为XLS格式
* @param fos
* @param bo
*/
public void writeExcelBo(FileOutputStream fos, java.util.Vector ve)
{
jxl.write.WritableWorkbook wwb;
try
{
wwb= Workbook.createWorkbook(fos);
jxl.write.WritableSheet ws= wwb.createSheet("booksheet", 10);
ws.addCell(new jxl.write.Label(0, 1, "书目ID"));
ws.addCell(new jxl.write.Label(1, 1, "ISBN"));
ws.addCell(new jxl.write.Label(2, 1, "定价"));
ws.addCell(new jxl.write.Label(3, 1, "书名"));
ws.addCell(new jxl.write.Label(4, 1, "原书名"));
ws.addCell(new jxl.write.Label(5, 1, "副题名"));
ws.addCell(new jxl.write.Label(6, 1, "着者"));
ws.addCell(new jxl.write.Label(7, 1, "译者"));
ws.addCell(new jxl.write.Label(8, 1, "版次"));
ws.addCell(new jxl.write.Label(9, 1, "出版地"));
ws.addCell(new jxl.write.Label(10, 1, "出版社"));
ws.addCell(new jxl.write.Label(11, 1, "出版日期"));
ws.addCell(new jxl.write.Label(12, 1, "页数"));
ws.addCell(new jxl.write.Label(13, 1, "书高"));
ws.addCell(new jxl.write.Label(14, 1, "装帧"));
ws.addCell(new jxl.write.Label(15, 1, "丛书名"));
ws.addCell(new jxl.write.Label(16, 1, "一般性附注项"));
ws.addCell(new jxl.write.Label(17, 1, "简介"));
ws.addCell(new jxl.write.Label(18, 1, "主题词"));
ws.addCell(new jxl.write.Label(19, 1, "中图法分类"));
ws.addCell(new jxl.write.Label(20, 1, "更新日期"));
ws.addCell(new jxl.write.Label(21, 1, "本数"));
book=new Book[ve.size()];
for (int i= 0; i < ve.size(); i++)
{
book[i]= (Book)ve.get(i);
ws.addCell(new jxl.write.Label(0, i + 2, "" + book[i].getBookId()));
ws.addCell(new jxl.write.Label(1, i + 2, book[i].getIsbn()));
ws.addCell(new jxl.write.Label(2, i + 2, "" + book[i].getPrice()));
ws.addCell(new jxl.write.Label(3, i + 2, book[i].getBookTitle()));
ws.addCell(new jxl.write.Label(4, i + 2, book[i].getOldFilename()));
ws.addCell(new jxl.write.Label(5, i + 2, book[i].getSubTitle()));
ws.addCell(new jxl.write.Label(6, i + 2, book[i].getWriter()));
ws.addCell(new jxl.write.Label(7, i + 2, book[i].getTranscribe()));
ws.addCell(new jxl.write.Label(8, i + 2, "" + book[i].getVersion()));
ws.addCell(new jxl.write.Label(9, i + 2, book[i].getPublishCity()));
ws.addCell(new jxl.write.Label(10, i + 2, book[i].getPublisher()));
ws.addCell(new jxl.write.Label(11, i + 2, book[i].getPublishDate().toString()));
ws.addCell(new jxl.write.Label(12, i + 2, "" + book[i].getPage()));
ws.addCell(new jxl.write.Label(13, i + 2, "" + book[i].getHight()));
ws.addCell(new jxl.write.Label(14, i + 2, book[i].getInstall()));
ws.addCell(new jxl.write.Label(15, i + 2, book[i].getSeries()));
ws.addCell(new jxl.write.Label(16, i + 2, book[i].getNotes()));
ws.addCell(new jxl.write.Label(17, i + 2, book[i].getPrecisnotes()));
ws.addCell(new jxl.write.Label(18, i + 2, book[i].getSubject()));
ws.addCell(new jxl.write.Label(19, i + 2, book[i].getCls().replaceAll("_", "")));
ws.addCell(new jxl.write.Label(20, i + 2, book[i].getUpdatedate().toString()));
ws.addCell(new jxl.write.Label(21, i + 2, "0"));
}
jxl.write.WritableFont wfc=
new jxl.write.WritableFont(
WritableFont.ARIAL,
255,
WritableFont.BOLD,
false,
UnderlineStyle.NO_UNDERLINE,
jxl.format.Colour.BLACK);
jxl.write.WritableCellFormat wcfFC= new jxl.write.WritableCellFormat(wfc);
ws.addCell(new jxl.write.Label(0, 0, "为保证您提交定单的稳定和正确，导入定单时候请勿更改此表格式（请勿更改书目ID,订购本数自行添加！）"));
wwb.write();
//关闭Excel工作薄对象
wwb.close();
} catch (IOException e)
{} catch (RowsExceededException e)
{} catch (WriteException e)
{}
}
//导入EXCEL
if (f.getName().indexOf(".xls") > 0)
{
try
{
fis= new FileInputStream(f);
BookBean bob= new BookBean();
UserBean usb= new UserBean();
jxl.Workbook rwb= Workbook.getWorkbook(fis);
jxl.Sheet sh= rwb.getSheet(0);
int rowCount= sh.getRows();
SimpleDateFormat sdf= new SimpleDateFormat("dd/MM/yyyy");
book= new Book[rowCount - 1];
for (int i= 1; i < rowCount; i++)
{
book[i - 1]= new Book();
jxl.Cell[] ce= sh.getRow(i);
book[i - 1].setIsbn(ce[0].getContents().toString());
book[i - 1].setSeries(ce[1].getContents().toString());
book[i - 1].setBookTitle(ce[2].getContents().toString());
book[i - 1].setWriter(ce[3].getContents().toString());
book[i - 1].setTranscribe(ce[4].getContents().toString());
book[i - 1].setPublisher(ce[5].getContents().toString());
book[i - 1].setPublishDate(sdf.parse(ce[6].getContents().toString(), new ParsePosition(0)));
book[i-1].setVersion(Integer.parseInt(ce[7].getContents().toString()));
book[i-1].setPage(Integer.parseInt(ce[8].getContents().toString()));
book[i-1].setCls(ce[9].getContents().toString());
book[i-1].setPrecisnotes(ce[10].getContents().toString());
book[i-1].setInstall(ce[11].getContents().toString());
book[i-1].setPrice(Float.parseFloat(ce[12].getContents().toString()));
book[i-1].setUserid(usb.getUser().getUserid());
getVector().addElement(book[i - 1]);
}
rwb.close();
fis.close();
} catch (FileNotFoundException e)
{} catch (BiffException e)
{} catch (IOException e)
{} catch (NumberFormatException e)
{
ShowMessage("数据导入失败，请按照本软件要求的EXCEL格式导入定单");
}
}
E. java从数据库中导出excel poi
这个我做奖金，考勤系统的时候经常用到，是一个方法，希望能帮到你。
用的apache poi:
/**
* 将奖金列表转换为奖金报表
* @param bonus
* @return byte[]
*/
private byte[] mainProcessBonusListToReport(List<Bonus> bonuses){
HSSFWorkbook hssfWorkbook = new HSSFWorkbook();
HSSFSheet hssfSheet =hssfWorkbook.createSheet("总奖金报表单");
/*第一行单元格合并*/
hssfSheet.addMergedRegion(new CellRangeAddress(0, 0, 0, 12));
/*第一行*/
HSSFRow hssfRow = hssfSheet.createRow(0);
HSSFCell hssfCell=hssfRow.createCell(0);
hssfCell.setCellValue("派单业务考核记录");
/*第二行*/
hssfRow = hssfSheet.createRow(1);
/*列名*/
String[] titles = {"序号","工号","话务员姓名","规范奖考核","业务奖金","话务奖金","服务质量奖金","星级系数","组长津贴","总奖金","增资奖金","英语翻译","实发总奖金"};
/*for循环生成列名*/
for (int i = 0; i < titles.length; i++) {
hssfCell = hssfRow.createCell(i);
hssfCell.setCellValue(titles[i]);
}
/*填充数据*/
int rowIndex=2;
for (Bonus bonus : bonuses) {
hssfRow = hssfSheet.createRow(rowIndex);
hssfCell = hssfRow.createCell(0);
hssfCell.setCellValue(rowIndex-1);
hssfCell = hssfRow.createCell(1);
hssfCell.setCellValue(bonus.getWorkNumber());
hssfCell = hssfRow.createCell(2);
hssfCell.setCellValue(bonus.getName());
hssfCell = hssfRow.createCell(3);
hssfCell.setCellValue(bonus.getStandardPerformance());
hssfCell = hssfRow.createCell(4);
hssfCell.setCellValue(bonus.getBusinessBonus());
hssfCell = hssfRow.createCell(5);
hssfCell.setCellValue(bonus.getCallBonus());
hssfCell = hssfRow.createCell(6);
hssfCell.setCellValue(bonus.getServiceQualityBonus());
hssfCell = hssfRow.createCell(7);
hssfCell.setCellValue(bonus.getStarCoefficient());
hssfCell = hssfRow.createCell(8);
hssfCell.setCellValue(bonus.getGroupLeaderAllowance());
hssfCell = hssfRow.createCell(9);
hssfCell.setCellValue(bonus.getTotalBonus());
hssfCell = hssfRow.createCell(10);
hssfCell.setCellValue(bonus.getAdditionalBonus());
hssfCell = hssfRow.createCell(11);
hssfCell.setCellValue(bonus.getEnglishTranslateBonus());
hssfCell = hssfRow.createCell(12);
hssfCell.setCellValue(bonus.getActualTotalBonus());
rowIndex++;
}
byte[] bytes = TypeUtils.HSSFWorkbookToByteArray(hssfWorkbook);
return bytes;
}
F. java数据库查询的结果导出到excel，数据没问题，就是加上一张照片导出时报错，报：null！详细如下
不是很明白你的意思，
但是看异常是空指针，应该了对某个对象进行取值或是如何，但对象为空，或是某个属性为空，但将空值进行某些操作（例如比较，system.out.println打印等）
G. java 数据库里面的数据 如何 让它 两天导出到excel表一次
孩子，这个不属于java的问题
数据库提供了导出为excel的功能，并且有定时器，所以去问数据库高手吧
H. 如何用java将数据库中的表导出到excel
第一步：如何用POI操作Excel
@Test
public void createXls() throws Exception{
//声明一个工作薄
HSSFWorkbook wb = new HSSFWorkbook();
//声明表
HSSFSheet sheet = wb.createSheet("第一个表");
//声明行
HSSFRow row = sheet.createRow(7);
//声明列
HSSFCell cel = row.createCell(3);
//写入数据
cel.setCellValue("你也好");
FileOutputStream fileOut = new FileOutputStream("d:/a/b.xls");
wb.write(fileOut);
fileOut.close();
}
第二步：导出指定数据库的所有表
分析：
1：某个数数据库有多少表，表名是什么？―――DataBaseMetadate.getMetadate().getTables(null,null,null,new String[]{Table}); - excel的文件名称。
2：对每一个表进行select * 操作。－每一个sheet的名称。
3：分析表结构，rs.getMetadate(); ResultSetMedated
4：多个列，列名是什么.－字段名就是sheet的第一行信息。
5：获取每一行的数据 – 放到sheet第一行以后。
@Test
public void export() throws Exception{
//声明需要导出的数据库
String dbName = "focus";
//声明book
HSSFWorkbook book = new HSSFWorkbook();
//获取Connection,获取db的元数据
Connection con = DataSourceUtils.getConn();
//声明statemen
Statement st = con.createStatement();
//st.execute("use "+dbName);
DatabaseMetaData dmd = con.getMetaData();
//获取数据库有多少表
ResultSet rs = dmd.getTables(dbName,dbName,null,new String[]{"TABLE"});
//获取所有表名－就是一个sheet
List<String> tables = new ArrayList<String>();
while(rs.next()){
String tableName = rs.getString("TABLE_NAME");
tables.add(tableName);
}
for(String tableName:tables){
HSSFSheet sheet = book.createSheet(tableName);
//声明sql
String sql = "select * from "+dbName+"."+tableName;
//查询数据
rs = st.executeQuery(sql);
//根据查询的结果，分析结果集的元数据
ResultSetMetaData rsmd = rs.getMetaData();
//获取这个查询有多少行
int cols = rsmd.getColumnCount();
//获取所有列名
//创建第一行
HSSFRow row = sheet.createRow(0);
for(int i=0;i<cols;i++){
String colName = rsmd.getColumnName(i+1);
//创建一个新的列
HSSFCell cell = row.createCell(i);
//写入列名
cell.setCellValue(colName);
}
//遍历数据
int index = 1;
while(rs.next()){
row = sheet.createRow(index++);
//声明列
for(int i=0;i<cols;i++){
String val = rs.getString(i+1);
//声明列
HSSFCell cel = row.createCell(i);
//放数据
cel.setCellValue(val);
}
}
}
con.close();
book.write(new FileOutputStream("d:/a/"+dbName+".xls"));
}
I. Java怎样将数据库中数据导出为Excel文件，求完整例子附带数据库。
下面是我写的一个运用jxl生成Excel文件的方法
该方法接收一个保存MarkesData数据的ArrayList arlist和文件生成路径Path
通过取得arlist里的数据生成Excel文件
感觉应该是你想要的 我没调试过也许有错 你也可以根据你的需要进行修改^_^
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import jxl.Workbook;
import jxl.write.Label;
import jxl.write.WritableSheet;
import jxl.write.WritableWorkbook;
import jxl.write.WriteException;
import jxl.write.biff.RowsExceededException;
public class WriteExcel {
WritableWorkbook book=null;
public void OutputExcel(ArrayList arlist,String Path){
try{
book = Workbook.createWorkbook(new File(Path));
//设置表名
WritableSheet sheet = book.createSheet("考试单",0);
//生成表格题头
Label labe1 = new Label(0, 0, "考生姓名" );
Label labe2 = new Label(1, 0, "地区");
Label labe3 = new Label(2, 0, "所属院校");
Label labe4 = new Label(3, 0, "班级");
Label labe5 = new Label(4, 0, "考试号");
Label labe6 = new Label(5, 0, "考试时间");
Label labe7 = new Label(6, 0, "科目名称");
//将生成的单元格添加到工作表中
sheet.addCell(labe1);
sheet.addCell(labe2);
sheet.addCell(labe3);
sheet.addCell(labe4);
sheet.addCell(labe5);
sheet.addCell(labe6);
sheet.addCell(labe7);
Iterator it = arlist.iterator();
int i = 1;
while(it.hasNext()){
//通过迭代获得arlist里的MarkesData对象
MarkesData temp = (MarkesData)it.next();
//取得数据生成单元格
Label label1=new Label(0,i,temp.getUser_name());
Label label2=new Label(1,i,temp.getArea_name());
Label label3=new Label(2,i,temp.getCollege_name());
Label label4=new Label(3,i,temp.getClass_name());
Label label5=new Label(4,i,temp.getTest_name());
Label label6=new Label(5,i,temp.getStarttime());
Label label7=new Label(6,i,temp.getSubject_name());
//将生成的单元格添加到工作表中
sheet.addCell(label1);
sheet.addCell(label2);
sheet.addCell(label3);
sheet.addCell(label4);
sheet.addCell(label5);
sheet.addCell(label6);
sheet.addCell(label7);
i++;
}
book.write();
book.close();
} catch (RowsExceededException e) {
e.printStackTrace();
} catch (WriteException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally{
try{
if(book!=null)book.close();
}catch(Exception e){
System.out.println("exception when closing Connection in finally");
System.out.println(e.getMessage().toString());
}
}
}
}
J. java在Action里面利用sql语句查询出来的数据导出Excel
分少，问题多，所以以下简答。。。。
利用POI 或JXL就可以，
public static void main(String[] arges){
try{
myExcel me = new myExcel();
//生成一个可读取的excel文件对象
me.workbook = Workbook.getWorkbook(new File("myfile.xls"));
//使用第一个工作表
me.sheet = me.workbook.getSheet(0);
//读一行记录，并显示出来
String[] ssTemp = me.readLine(1);
for(int i=0;i<ssTemp.length;i++)
System.out.println(ssTemp[i]);
//写入数据
me.write();
me.workbook.close();
}catch(Exception e){
System.out.println(e);
}
或者利用displaytag标签库本身的到处功能