Java程序连接数据库查询再导出Excel中
- - Java - 编程语言 - ITeye博客 * 到处Excel文件的Action. // 调用导出方法. * @param col 所要导出对象集合. FileOutputStream out = new FileOutputStream("d://"+"导出excel数据"+System.currentTimeMillis() + ".xls");.
Java程序连接数据库查询再导出Excel中
标签：
java
程序
数据库
| 发表时间：2014-10-25 19:13 | 作者：songlei8090
出处：http://www.iteye.com
package com.unisys;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFFont;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.util.HSSFColor;
import org.apache.poi.hssf.util.Region;
public class Excels {
/**
* 到处Excel文件的Action
* @return
* @throws Exception
* @throws Exception
* @throws Exception
*/
public static void main(String[] args) throws Exception {
List userList = findDate();
// 调用导出方法
try {
export(userList);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
/**
* 导出操作
* @param col 所要导出对象集合
*/
private static void export(List<String[]> col) throws Exception {
FileOutputStream out = new FileOutputStream("d://"+"导出excel数据"+System.currentTimeMillis() + ".xls");
BufferedInputStream bis = null;
BufferedOutputStream bos = null;
try {
bis = new BufferedInputStream(getExcelInputStream(col));
bos = new BufferedOutputStream(out);
byte[] buff = new byte[4096];
int bytesRead;
// Simple read/write loop.
while (-1 != (bytesRead = bis.read(buff, 0, buff.length))) {
bos.write(buff, 0, bytesRead);
}
} catch (Exception e) {
throw e;
} finally {
if (bis != null)
bis.close();
if (bos != null)
bos.close();
}
}
private static InputStream getExcelInputStream(List col) throws Exception, NoSuchMethodException, IllegalAccessException {
HSSFWorkbook wb = new HSSFWorkbook();
HSSFSheet sheet=null;
HSSFCellStyle titleStyle=null;
Short count = 2;
int flag=0;
int tiao=700;
//判断几个sheet表
if(col.size()%tiao==0){
flag=col.size()/tiao;
}else{
flag=col.size()/tiao+1;
}
int j=1;
//控制表的张数
for (int i = 0; i < flag; i++) {
sheet = wb.createSheet("sheet"+(i+1));
titleStyle = wb.createCellStyle();
titleStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
titleStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
HSSFFont font = wb.createFont();
font.setColor(HSSFColor.BLACK.index);
font.setFontHeightInPoints((short)
;
font.setItalic(false);
font.setStrikeout(false);
font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
titleStyle.setFont(font);
//中间对齐的格式
HSSFCellStyle centerStyle = wb.createCellStyle();
centerStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
centerStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
//右边对齐的格式
HSSFCellStyle rightStyle = wb.createCellStyle();
rightStyle.setAlignment(HSSFCellStyle.ALIGN_RIGHT);
rightStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
//为sheet生成标题Row的所有类容
processExcelHeader(sheet, titleStyle);
//处理每个列的宽度
processCellWidth(sheet);
//控制每张表的条数
for (;j < col.size()+1; j++) {
if(j%tiao==0){
processElectricitybillBasestationToExcel((String[])col.get(j-1), count, sheet, centerStyle, rightStyle);
count = (short) (count + 1);
count=2;
break;
}
processElectricitybillBasestationToExcel((String[])col.get(j-1), count, sheet, centerStyle, rightStyle);
count = (short) (count + 1);
}
j++;
}
count = (short) (count + 2);
/* for (Iterator ite = col.iterator(); ite.hasNext();) {
//将信息写入Excel中
processElectricitybillBasestationToExcel((StuModel) ite.next(), count, sheet, centerStyle, rightStyle);
count = (short) (count + 1);
}*/
//合计
HSSFRow row = sheet.createRow(count);
//第一行的单元格
HSSFCell cell = null;
cell = row.createCell((short) 0);
// cell.setEncoding(HSSFCell.ENCODING_UTF_16);
cell.setCellValue("数据总计："+col.size());
cell.setCellStyle(titleStyle);
cell = row.createCell((short) 1);
sheet.addMergedRegion(new Region(count, (short) 0, count, (short) 7));
ByteArrayOutputStream os = new ByteArrayOutputStream();
try {
wb.write(os);
} catch (IOException e) {
e.printStackTrace();
}
byte[] content = os.toByteArray();
InputStream is = new ByteArrayInputStream(content);
return is;
}
/**
* 处理Excel的标题栏
* @param sheet
* @param titleStyle
*/
private static void processExcelHeader(HSSFSheet sheet, HSSFCellStyle titleStyle) {
//行号
//第一行
HSSFRow row = sheet.createRow(0);
//第二行
HSSFRow sRow = sheet.createRow(1);
//第一行的单元格
HSSFCell cell = null;
//第二行的单元格
HSSFCell sCell = null;
//序号
cell = row.createCell((short) 0);
cell.setCellStyle(titleStyle);
// cell.setEncoding(HSSFCell.ENCODING_UTF_16);
cell.setCellStyle(titleStyle);
cell.setCellValue("序号");
sCell = sRow.createCell((short) 0);
sheet.addMergedRegion(new Region(0, (short) 0, 1, (short) 0));
//clcustid
cell = row.createCell((short) 1);
cell.setCellStyle(titleStyle);
cell.setCellValue("CLCUSTID");
sCell = sRow.createCell((short) 1);
sheet.addMergedRegion(new Region(0, (short) 1, 1, (short) 1));
cell.setCellStyle(titleStyle);
//csrname
cell = row.createCell((short) 2);
cell.setCellStyle(titleStyle);
cell.setCellValue("custname");
sCell = sRow.createCell((short) 2);
sheet.addMergedRegion(new Region(0, (short) 2, 1, (short) 2));
//clcallid
cell = row.createCell((short) 3);
cell.setCellStyle(titleStyle);
cell.setCellValue("CLCALLID");
sCell = sRow.createCell((short) 3);
sheet.addMergedRegion(new Region(0, (short) 3, 1, (short) 3));
//clcalltime
cell = row.createCell((short) 4);
cell.setCellStyle(titleStyle);
cell.setCellValue("CLCALLTIME");
sCell = sRow.createCell((short) 4);
sheet.addMergedRegion(new Region(0, (short) 4, 1, (short) 4));
//clcsrid
cell = row.createCell((short) 5);
cell.setCellStyle(titleStyle);
cell.setCellValue("CLCSRID");
sCell = sRow.createCell((short) 5);
sheet.addMergedRegion(new Region(0, (short) 5, 1, (short) 5));
//clclitelno
cell = row.createCell((short) 6);
cell.setCellStyle(titleStyle);
cell.setCellValue("CLCLITELNO");
sCell = sRow.createCell((short) 6);
sheet.addMergedRegion(new Region(0, (short) 6, 1, (short) 6));
//callreasontype
cell = row.createCell((short) 7);
cell.setCellStyle(titleStyle);
cell.setCellValue("CALLREASONTYPE");
sCell = sRow.createCell((short) 7);
sheet.addMergedRegion(new Region(0, (short) 7, 1, (short) 7));
//callreason
cell = row.createCell((short);
cell.setCellStyle(titleStyle);
cell.setCellValue("CALLREASON");
sCell = sRow.createCell((short);
sheet.addMergedRegion(new Region(0, (short) 8, 1, (short));
}
/**
* 全局控制 多少列
* @param sheet
*/
private static void processCellWidth(HSSFSheet sheet) {
sheet.setColumnWidth((short) 0, (short) (10 * 256));
sheet.setColumnWidth((short) 1, (short) (15 * 256));
sheet.setColumnWidth((short) 2, (short) (15 * 256));
sheet.setColumnWidth((short) 3, (short) (20 * 256));
sheet.setColumnWidth((short) 4, (short) (20 * 256));
sheet.setColumnWidth((short) 5, (short) (20 * 256));
sheet.setColumnWidth((short) 6, (short) (15 * 256));
sheet.setColumnWidth((short) 7, (short) (15 * 256));
sheet.setColumnWidth((short) 8, (short) (15 * 256));
}
/**
* 将 要导出的数据 的信息填充到Excel中
* @param eb
* @param count
* @param sheet
* @param centerStyle
* @throws Exception
*/
private static void processElectricitybillBasestationToExcel(String[] str, Short count, HSSFSheet sheet, HSSFCellStyle centerStyle, HSSFCellStyle rightStyle) throws Exception {
//根据基站编号取得基站信息
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM");
java.text.DecimalFormat df = new java.text.DecimalFormat("#.00");
//行号
//第一行
HSSFRow row = sheet.createRow(count);
//第一行的单元格
HSSFCell cell = null;
//序号
cell = row.createCell((short) 0);
// cell.setEncoding(HSSFCell.ENCODING_UTF_16);
cell.setCellValue(count - 1);
cell.setCellStyle(centerStyle);
//车号
cell = row.createCell((short) 1);
cell.setCellStyle(centerStyle);
// cell.setEncoding(HSSFCell.ENCODING_UTF_16);
cell.setCellValue(str[1]);
//车辆型号
cell = row.createCell((short) 2);
// cell.setEncoding(HSSFCell.ENCODING_UTF_16);
cell.setCellStyle(centerStyle);
cell.setCellValue(str[0]);
}
public static List<String[]> findDate() throws Exception
{
List<String[]> list=new ArrayList<String[]>();
Connection conn = null;
try {
Class.forName("oracle.jdbc.driver.OracleDriver");
String url = "jdbc:oracle:thin:@localhost:1521:orcl";
conn = DriverManager.getConnection(url, "sl", "sl");
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
String sql="select * from student";
PreparedStatement ps = conn.prepareStatement(sql);
ResultSet rs= ps.executeQuery();
while(rs.next()){
String[] s=new String[2];
s[0]=rs.getString("stuId");
s[1]=rs.getString("stuName");
list.add(s);
}
ps.execute();
ps.close();
conn.close();
return list;
}
}
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import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFFont;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.util.HSSFColor;
import org.apache.poi.hssf.util.Region;
public class Excels {
/**
* 到处Excel文件的Action
* @return
* @throws Exception
* @throws Exception
* @throws Exception
*/
public static void main(String[] args) throws Exception {
List userList = findDate();
// 调用导出方法
try {
export(userList);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
/**
* 导出操作
* @param col 所要导出对象集合
*/
private static void export(List<String[]> col) throws Exception {
FileOutputStream out = new FileOutputStream("d://"+"导出excel数据"+System.currentTimeMillis() + ".xls");
BufferedInputStream bis = null;
BufferedOutputStream bos = null;
try {
bis = new BufferedInputStream(getExcelInputStream(col));
bos = new BufferedOutputStream(out);
byte[] buff = new byte[4096];
int bytesRead;
// Simple read/write loop.
while (-1 != (bytesRead = bis.read(buff, 0, buff.length))) {
bos.write(buff, 0, bytesRead);
}
} catch (Exception e) {
throw e;
} finally {
if (bis != null)
bis.close();
if (bos != null)
bos.close();
}
}
private static InputStream getExcelInputStream(List col) throws Exception, NoSuchMethodException, IllegalAccessException {
HSSFWorkbook wb = new HSSFWorkbook();
HSSFSheet sheet=null;
HSSFCellStyle titleStyle=null;
Short count = 2;
int flag=0;
int tiao=700;
//判断几个sheet表
if(col.size()%tiao==0){
flag=col.size()/tiao;
}else{
flag=col.size()/tiao+1;
}
int j=1;
//控制表的张数
for (int i = 0; i < flag; i++) {
sheet = wb.createSheet("sheet"+(i+1));
titleStyle = wb.createCellStyle();
titleStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
titleStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
HSSFFont font = wb.createFont();
font.setColor(HSSFColor.BLACK.index);
font.setFontHeightInPoints((short)
;
font.setItalic(false);
font.setStrikeout(false);
font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
titleStyle.setFont(font);
//中间对齐的格式
HSSFCellStyle centerStyle = wb.createCellStyle();
centerStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
centerStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);
//右边对齐的格式
HSSFCellStyle rightStyle = wb.createCellStyle();
rightStyle.setAlignment(HSSFCellStyle.ALIGN_RIGHT);
rightStyle.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);
//为sheet生成标题Row的所有类容
processExcelHeader(sheet, titleStyle);
//处理每个列的宽度
processCellWidth(sheet);
//控制每张表的条数
for (;j < col.size()+1; j++) {
if(j%tiao==0){
processElectricitybillBasestationToExcel((String[])col.get(j-1), count, sheet, centerStyle, rightStyle);
count = (short) (count + 1);
count=2;
break;
}
processElectricitybillBasestationToExcel((String[])col.get(j-1), count, sheet, centerStyle, rightStyle);
count = (short) (count + 1);
}
j++;
}
count = (short) (count + 2);
/* for (Iterator ite = col.iterator(); ite.hasNext();) {
//将信息写入Excel中
processElectricitybillBasestationToExcel((StuModel) ite.next(), count, sheet, centerStyle, rightStyle);
count = (short) (count + 1);
}*/
//合计
HSSFRow row = sheet.createRow(count);
//第一行的单元格
HSSFCell cell = null;
cell = row.createCell((short) 0);
// cell.setEncoding(HSSFCell.ENCODING_UTF_16);
cell.setCellValue("数据总计："+col.size());
cell.setCellStyle(titleStyle);
cell = row.createCell((short) 1);
sheet.addMergedRegion(new Region(count, (short) 0, count, (short) 7));
ByteArrayOutputStream os = new ByteArrayOutputStream();
try {
wb.write(os);
} catch (IOException e) {
e.printStackTrace();
}
byte[] content = os.toByteArray();
InputStream is = new ByteArrayInputStream(content);
return is;
}
/**
* 处理Excel的标题栏
* @param sheet
* @param titleStyle
*/
private static void processExcelHeader(HSSFSheet sheet, HSSFCellStyle titleStyle) {
//行号
//第一行
HSSFRow row = sheet.createRow(0);
//第二行
HSSFRow sRow = sheet.createRow(1);
//第一行的单元格
HSSFCell cell = null;
//第二行的单元格
HSSFCell sCell = null;
//序号
cell = row.createCell((short) 0);
cell.setCellStyle(titleStyle);
// cell.setEncoding(HSSFCell.ENCODING_UTF_16);
cell.setCellStyle(titleStyle);
cell.setCellValue("序号");
sCell = sRow.createCell((short) 0);
sheet.addMergedRegion(new Region(0, (short) 0, 1, (short) 0));
//clcustid
cell = row.createCell((short) 1);
cell.setCellStyle(titleStyle);
cell.setCellValue("CLCUSTID");
sCell = sRow.createCell((short) 1);
sheet.addMergedRegion(new Region(0, (short) 1, 1, (short) 1));
cell.setCellStyle(titleStyle);
//csrname
cell = row.createCell((short) 2);
cell.setCellStyle(titleStyle);
cell.setCellValue("custname");
sCell = sRow.createCell((short) 2);
sheet.addMergedRegion(new Region(0, (short) 2, 1, (short) 2));
//clcallid
cell = row.createCell((short) 3);
cell.setCellStyle(titleStyle);
cell.setCellValue("CLCALLID");
sCell = sRow.createCell((short) 3);
sheet.addMergedRegion(new Region(0, (short) 3, 1, (short) 3));
//clcalltime
cell = row.createCell((short) 4);
cell.setCellStyle(titleStyle);
cell.setCellValue("CLCALLTIME");
sCell = sRow.createCell((short) 4);
sheet.addMergedRegion(new Region(0, (short) 4, 1, (short) 4));
//clcsrid
cell = row.createCell((short) 5);
cell.setCellStyle(titleStyle);
cell.setCellValue("CLCSRID");
sCell = sRow.createCell((short) 5);
sheet.addMergedRegion(new Region(0, (short) 5, 1, (short) 5));
//clclitelno
cell = row.createCell((short) 6);
cell.setCellStyle(titleStyle);
cell.setCellValue("CLCLITELNO");
sCell = sRow.createCell((short) 6);
sheet.addMergedRegion(new Region(0, (short) 6, 1, (short) 6));
//callreasontype
cell = row.createCell((short) 7);
cell.setCellStyle(titleStyle);
cell.setCellValue("CALLREASONTYPE");
sCell = sRow.createCell((short) 7);
sheet.addMergedRegion(new Region(0, (short) 7, 1, (short) 7));
//callreason
cell = row.createCell((short)
;
cell.setCellStyle(titleStyle);
cell.setCellValue("CALLREASON");
sCell = sRow.createCell((short)
;
sheet.addMergedRegion(new Region(0, (short) 8, 1, (short)
);
}
/**
* 全局控制 多少列
* @param sheet
*/
private static void processCellWidth(HSSFSheet sheet) {
sheet.setColumnWidth((short) 0, (short) (10 * 256));
sheet.setColumnWidth((short) 1, (short) (15 * 256));
sheet.setColumnWidth((short) 2, (short) (15 * 256));
sheet.setColumnWidth((short) 3, (short) (20 * 256));
sheet.setColumnWidth((short) 4, (short) (20 * 256));
sheet.setColumnWidth((short) 5, (short) (20 * 256));
sheet.setColumnWidth((short) 6, (short) (15 * 256));
sheet.setColumnWidth((short) 7, (short) (15 * 256));
sheet.setColumnWidth((short) 8, (short) (15 * 256));
}
/**
* 将 要导出的数据 的信息填充到Excel中
* @param eb
* @param count
* @param sheet
* @param centerStyle
* @throws Exception
*/
private static void processElectricitybillBasestationToExcel(String[] str, Short count, HSSFSheet sheet, HSSFCellStyle centerStyle, HSSFCellStyle rightStyle) throws Exception {
//根据基站编号取得基站信息
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM");
java.text.DecimalFormat df = new java.text.DecimalFormat("#.00");
//行号
//第一行
HSSFRow row = sheet.createRow(count);
//第一行的单元格
HSSFCell cell = null;
//序号
cell = row.createCell((short) 0);
// cell.setEncoding(HSSFCell.ENCODING_UTF_16);
cell.setCellValue(count - 1);
cell.setCellStyle(centerStyle);
//车号
cell = row.createCell((short) 1);
cell.setCellStyle(centerStyle);
// cell.setEncoding(HSSFCell.ENCODING_UTF_16);
cell.setCellValue(str[1]);
//车辆型号
cell = row.createCell((short) 2);
// cell.setEncoding(HSSFCell.ENCODING_UTF_16);
cell.setCellStyle(centerStyle);
cell.setCellValue(str[0]);
}
public static List<String[]> findDate() throws Exception
{
List<String[]> list=new ArrayList<String[]>();
Connection conn = null;
try {
Class.forName("oracle.jdbc.driver.OracleDriver");
String url = "jdbc:oracle:thin:@localhost:1521:orcl";
conn = DriverManager.getConnection(url, "sl", "sl");
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
String sql="select * from student";
PreparedStatement ps = conn.prepareStatement(sql);
ResultSet rs= ps.executeQuery();
while(rs.next()){
String[] s=new String[2];
s[0]=rs.getString("stuId");
s[1]=rs.getString("stuName");
list.add(s);
}
ps.execute();
ps.close();
conn.close();
return list;
}
}
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- - Taobao QA Team“dynaTrace Ajax是一个详细的底层追踪工具，它不仅可以显示所有请求和文件在网络中传输的时间，还会记录浏览器Render、CPU消耗、JavaScript解析和运行情况等详细的信息，而这些也只是dynaTrace Ajax的冰山一角. showslow平台同样采集了dynatrace的数据，所以做为kelude平台前端页面测试组件，同样要支持dynatrace数据的获取，该代码由云晰同学编写维护：.
Java程序员常用工具集
- - BlogJava-庄周梦蝶 我发现很多人没办法高效地解决问题的关键原因是不熟悉工具，不熟悉工具也还罢了，甚至还不知道怎么去找工具，这个问题就大条了. 我想列下我能想到的一个Java程序员会用到的常用工具. 1.IDE： Eclipse或者 IDEA，熟悉尽可能多的快捷键，《 Eclipse常见快捷键列表》. (1) Findbugs，在release之前进行一次静态代码检查是必须的.
Java系统程序员修炼之道
- - 博客 - 伯乐在线从2002开始接触Java学会HelloWorld这么经典的程序到如今不知不觉已经十年啦，十年中亲耳听到过不少大牛的演讲，见到过项目中的神人在键盘上运指如飞的编程速度，当时就被震撼了. 当编程越来越成体力活，我们还能有自己的思想，还能修炼为Java系统级别的 程序员嘛. 学习与修炼以下知识与技能，帮你早日达成愿望.
Java程序挂掉的几种可能
- - Java译站今天花了一整天在跟踪一个问题，每次感觉已经快找到原因的时候发现现象又变了，我觉得从中吸取的教训可以给大家分享一下. 为了重现这个现象，我写了一个简单的例子. 在本例中，先初始化了一个map，然后用一个无限循环将一些键值对插入到map里面：. 你可能也猜到了，这段代码编译执行后无法正常结束. 我会在终端中看到java.lang.OutOfMemoryError: GC overhead limit exceeded的异常信息.
准确的java程序性能测试
- - ITeye博客原创文章，转载请指明出处： http://aub.iteye.com/blog/2124974 ， 尊重他人即尊重自己. 1.避免垃圾回收对结果造成的误差. 方案一：JVM启动时使用-verbose:gc观察垃圾回收动作，确认整个测试期间垃圾回收根本不会执行. 方案二：运行足够的次数和时间，这样测试程序能够充分的反应出运行期间分配与垃圾回收的开销（推荐）.