JDBC读写oracle大字段BLOB
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一 JDBC將大字段BLoB內容寫入到Oracle數據庫(寫大字段BLOB)
例子的詳細信息參照為技改大修批量生成數據寫的小工具
1.1 構建界面MyNotePad.java
package test;
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import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
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import javax.swing.ButtonGroup;
import javax.swing.JButton;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JRadioButton;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
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public class MyNotePad extends JFrame {
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private JTextField filenameTf = new JTextField(),dirTf? = new JTextField(),xmmcTf = new JTextField(),userNameTf = new JTextField();
private JLabel fileNameLabel? = new JLabel("文件名："),filePathLable= new JLabel("文件路徑："),xmmcLable = new JLabel("項目名稱："),userNameLabel=new JLabel("賬號：");
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private JButton openBt = new JButton("選擇可研報告");
private JButton saveBt = new JButton("生成項目");
private JPanel optPane = new JPanel();
private JPanel navigatePane = new JPanel();
private JTextArea contentTa = new JTextArea(5,20);
private JRadioButton rb1 = new JRadioButton("技改",true), rb2 = new JRadioButton("大修");
private ButtonGroup group= new ButtonGroup();
private String lx="技改";
public static boolean isReady = false;
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public MyNotePad(String title)
{
super(title);
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openBt.addActionListener(new OpenHandler());
optPane.add(openBt);
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saveBt.addActionListener(new SaveHandler());
optPane.add(saveBt);
dirTf.setEditable(false);
filenameTf.setEditable(false);
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group.add(rb1);group.add(rb2);
rb1.addActionListener(listener2);
rb2.addActionListener(listener2);
navigatePane.setLayout(new GridLayout(5,2));
navigatePane.add(fileNameLabel);
navigatePane.add(filenameTf);
navigatePane.add(filePathLable);
navigatePane.add(dirTf);
navigatePane.add(xmmcLable);
navigatePane.add(xmmcTf);
navigatePane.add(rb1);
navigatePane.add(rb2);
navigatePane.add(userNameLabel);
navigatePane.add(userNameTf);
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Container contentPane = this.getContentPane();
contentPane.add(navigatePane,BorderLayout.NORTH);
contentPane.add(optPane,BorderLayout.SOUTH);
contentPane.add(new JScrollPane(contentTa),BorderLayout.CENTER);
this.setSize(600,600);
this.setVisible(true);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
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private ActionListener listener2 = new ActionListener(){
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public void actionPerformed(ActionEvent actionEvent) {
JRadioButton rb = (JRadioButton)actionEvent.getSource();
lx = rb.getText();
}
};
class OpenHandler implements ActionListener {
public void actionPerformed(ActionEvent actionEvent) {
JFileChooser jc = new JFileChooser();//文件選擇
int rVal = jc.showOpenDialog(MyNotePad.this );
if( rVal==JFileChooser.APPROVE_OPTION){
File dir = jc.getCurrentDirectory();//文件路徑
File file = jc.getSelectedFile();
filenameTf.setText(file.getName());
dirTf.setText(dir.toString());
isReady = true;
}
}
}
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class SaveHandler implements ActionListener{
public void actionPerformed(ActionEvent actionEvent) {
if( isReady){
String fileName = getFilenameTf().getText();
String fileDir = getDirTf().getText();
String xmmc = xmmcTf.getText();
System.out.println("xmmc="+xmmc+"xmmc.length="+xmmc.length());
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if( xmmc==null||xmmc.trim()==""||xmmc.length()<=0)
{
JOptionPane.showMessageDialog(MyNotePad.this, "請先輸入項目名稱");
return;
}
String userName = userNameTf.getText();
if( userName==null||userName.trim()==""||userName.length()<=0)
{
JOptionPane.showMessageDialog(MyNotePad.this, "請先輸入人員賬號");
return;
}
//fileDir+"//"+fileName是文件路徑，加上文件的名稱
if( CreateXM.createDxxm(lx,fileDir+"//"+fileName,fileName,10,userName,contentTa,xmmc)){
JOptionPane.showMessageDialog(MyNotePad.this, "批量生成項目成功");
}else
{
JOptionPane.showMessageDialog(MyNotePad.this, "批量生成項目失敗");
}
}else
{
JOptionPane.showMessageDialog(MyNotePad.this, "請先選擇可研報告");
return;
}
}
}
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public JTextField getFilenameTf() {
return filenameTf;
}
public JTextField getDirTf() {
return dirTf;
}
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public static void main(String []args)
{
new MyNotePad("批量生成項目");
//System.out.println("測試Helloword!");
}
}
1.2 實現生成項目的功能(包括傳入大字段數據Blob到數據庫的功能)
package test;
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import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Random;
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import javax.swing.JTextArea;
/**
* 批量生成技改大修項目
* 主要的功能點：可研報告文件存儲在數據庫中
* @author fy
*
*/
public class CreateXM {
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public static boolean createDxxm(String jgOrDxString ,String filePath,String fileName,int sl,String userName,JTextArea jTextArea,String xmmcPre){
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Connection conn=null;
try {
conn = ConnectionFactory.getConnection();
} catch (Exception e3) {
PrintComm.println("數據庫連接失敗", jTextArea);
return false;
}
if( conn==null)
{
PrintComm.println("數據庫連接失敗", jTextArea);
return false;
}
SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm");
Date now = new Date();
String bzsj = df.format(now);
Statement psmt = null;
ResultSet rs = null;
String xmlx = "";
String zylb = "";
String zyxf ="";
String gzyy="";//改造原因
String[] xmlxArr? ={"70101","70102","70103"};
List<String> zylbArr =new ArrayList<String>();//{"70201","70202","70203","70299"};
zylbArr.add("70201");
zylbArr.add("70202");
zylbArr.add("70203");
zylbArr.add("70299");
List<String> gzyyList = null;
Random random = null;
String kybgAttr = "5F4EBE72-B09C-4AD6-A623-085B9F2AE982";
String bzr = "";
String bzbm = "";
String userID = "";
String dsgs? ="";
String wsgs="";
String qygs="";
String selBzrSql = "select empid,deptid,user_id from mw_app.mwv_om_userinfo userinfo where userinfo.user_name='"+userName+"' ";
try {
psmt = conn.createStatement();
rs? = psmt.executeQuery(selBzrSql);
if(rs.next())
{
bzr = rs.getString(1);
bzbm = rs.getString(2);
userID = rs.getString(3);
}
} catch (SQLException e2) {
e2.printStackTrace();
}
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PrintComm.println("bzr="+bzr+",bzbm="+bzbm+",userID="+userID, jTextArea);
String? dldWsql = "select frdw.obj_id, frdw.mc, frdw.dwjb, dwjb.JBMC from (select obj_id, mc, dwjb from mw_sys.MWT_PD_DEPS ";
dldWsql +="where SFCX='63785359-B0D9-4548-8F18-4F8FD682D684'? and dwjb is not null and SFDLDW = 'T' start with obj_id = (select lsbm from mw_sys.MWT_PD_EMPS where ";
dldWsql +="sysuserid ='"+userID+"' and ZZQK='00F94133-B7A4-42E1-8C0B-3639993F5486' ) connect by prior sjbm = obj_id)frdw,mw_app.MWT_UD_GY_DWJB dwjb ";
dldWsql +="where dwjb.JBBH = frdw.dwjb and frdw.dwjb < 8 order by dwjb desc ";
try {
rs = psmt.executeQuery(dldWsql);
while(rs.next())
{
String dwjb=rs.getString(3);
System.out.println("dwjb==="+dwjb);
if( dwjb.equals("4"))//單位級別是地市級電網的
{
dsgs = rs.getString(1);
System.out.println("dwjb.equals(/"4/"),dsgs="+dsgs);
}
if(dwjb.equals("3"))//單位級別是網省公司的
{
wsgs = rs.getString(1);
System.out.println("dwjb.equals(/"3/"),wsgs="+wsgs);
}
if(dwjb.equals("2"))//單位級別是區域公司的
{
qygs = rs.getString(1);
System.out.println("dwjb.equals(/"2/"),qygs="+qygs);
}
}
} catch (SQLException e2) {
e2.printStackTrace();
}
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if( "技改"==jgOrDxString)
{
kybgAttr="594F3551-3F2E-456C-B5BF-AD029BCD2FF4";
zylbArr.add("70204");
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String gzyySql = "select bzdm from MW_APP.MWT_UD_GG_DM WHERE DMLB = '723' ";
try {
psmt = conn.createStatement();
rs? = psmt.executeQuery(gzyySql);
gzyyList = new ArrayList<String>();
while(rs.next())
{
gzyyList.add(rs.getString(1));
}
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random = new Random();
int gzyyIndex = random.nextInt(gzyyList.size()-1);
System.out.println("gzyyIndex==="+gzyyIndex);
PrintComm.println("gzyyIndex="+gzyyIndex, jTextArea);
gzyy = gzyyList.get(gzyyIndex);
} catch (SQLException e1) {
e1.printStackTrace();
}
}
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String sfcyh="T";//是否差異化補強改造
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List<String> zyxfList = null;
try {
for( int i = 1;i<=sl;i++){
String xmmc = bzsj+xmmcPre+"-"+i;
System.out.println("xmmc="+xmmc);
PrintComm.println("xmmc="+xmmc,jTextArea);
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random = new Random();
int xmlxIndex = random.nextInt(xmlxArr.length-1);
xmlx = xmlxArr[xmlxIndex];
random = new Random();
int zylbIndex = random.nextInt(zylbArr.size()-1);
zylb=zylbArr.get(zylbIndex);
String sql = "SELECT DM, DMMC FROM MW_APP.MWT_UD_GG_DM WHERE DMLB = '703' and dm<>'70305' and bzdm like (select bzdm from mw_app.mwt_ud_gg_dm where dm = '"+zylb+"')||'%'";
psmt = conn.createStatement();
rs? = psmt.executeQuery(sql);
zyxfList = new ArrayList<String>();
while(rs.next())
{
zyxfList.add(rs.getString(1));
}
random = new Random();
if( zyxfList.size()==1)
{
zyxf = zyxfList.get(0);
}else if( zyxfList.size()>1)
{
int zyxfIndex = random.nextInt(zyxfList.size()-1);
zyxf = zyxfList.get(zyxfIndex);
}
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String dydj = "13";
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String dxmd="70403";
String zycd = "70602"; String zcxz= "00403";
String xmzt = "71102";? String qtxmsx = "";? String sfnw = "F";?? String sfkqdwxm = "F";
String xmid = "";
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int ztz = 0;
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psmt = conn.createStatement();
rs = psmt.executeQuery("select mw_sys.newguid||'-'||substr('0000'||rownum,-5,5), round(dbms_random.value(400,1)) from dual");
if(rs.next()){
xmid = rs.getString(1);
ztz = rs.getInt(2);
}
PrintComm.println("xmid="+xmid+",ztz="+ztz, jTextArea);
String insertSql = "insert into mw_app.mwt_ud_jgdx_dxxmk (obj_id,obj_dispidx,bzr,bzbm,bzsj,xmmc,kb,znhbdz,xmlx,zylb,zyxf,dydj,dxmd,zycd,xmkssj,xmwcsj,zcxz,ztz,jhnd,xmzt,qtxmsx,sfnw,sfkqdwxm,xmnr,wsgs,dsgs,qygs) ";
insertSql+="select '"+xmid+"', mw_sys.mwq_obj_dispidx.nextval,'"+bzr+"','"+bzbm+"',sysdate,'"+xmmc+"','1' ,0? ";
insertSql+=",'"+xmlx+"','"+zylb+"','"+zyxf+"','"+dydj+"','"+dxmd+"','"+zycd+"',to_date('2012-01','yyyy-MM'),to_date('2012-12','yyyy-MM'),'"+zcxz+"','"+ztz+"','2012','"+xmzt+"','"+qtxmsx+"','"+sfnw+"','"+sfkqdwxm+"','"+xmmc+"','"+wsgs+"','"+dsgs+"','"+qygs+"' ";
insertSql+=" from dual";
if( "技改"==jgOrDxString){
insertSql = "insert into mw_app.mwt_ud_jgdx_jgxmk (TGDWSSNL,obj_id,obj_dispidx,bzr,bzbm,bzsj,xmmc,kb,znhbdz,xmlx,zylb,zyxf,dydj,gzmd,zycd,xmkssj,xmwcsj,zcxz,ztz,bznd,xmzt,qtxmsx,sfnw,sfkqdwxm,xmnr,wsgs,jglx,lxyj,bz,sfknxm,dsgs,qygs) ";
insertSql+="select 1,'"+xmid+"', mw_sys.mwq_obj_dispidx.nextval,'"+bzr+"','"+bzbm+"',sysdate,'"+xmmc+"','1' ,0? ";
insertSql+=",'"+xmlx+"','"+zylb+"','"+zyxf+"','"+dydj+"','"+dxmd+"','"+zycd+"',to_date('2012-01','yyyy-MM'),to_date('2012-12','yyyy-MM'),'"+zcxz+"','"+ztz+"','2012','"+xmzt+"','"+qtxmsx+"','"+sfnw+"','"+sfkqdwxm+"','"+xmmc+"','"+wsgs+"','70501','"+gzyy+"','否','是','"+dsgs+"','"+qygs+"' ";
insertSql+=" from dual";
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String insertNdtzSql = "insert into mw_app.mwt_ud_jgdx_ndtzqk(obj_id,obj_dispidx,xmid,nd,zjjh) ";
insertNdtzSql+=" select mw_sys.newguid||'-'||substr('0000'||rownum,-5,5),mw_sys.mwq_obj_dispidx.nextval , '"+xmid+"','2012','"+ztz+"' from dual ";
psmt.addBatch(insertNdtzSql);
}
PrintComm.println("insertSql="+insertSql, jTextArea);
psmt.addBatch(insertSql);
psmt.executeBatch();
if ("70202"==zylb||"70203"==zylb){//如果是電網一次和二次系統要添加規模
insertSql? = "insert into mw_app.mwt_ud_jgdx_gzgm (obj_id,obj_dispidx,xmid,dydj,jldw,sl,zjjh)";
insertSql+="select mw_sys.newguid||'-'||substr('0000'||rownum,-5,5),mw_sys.mwq_obj_dispidx.nextval,'"+xmid+"',2, '臺',3,"+ztz+" from dual";
System.out.println("insertSql="+insertSql);
psmt.execute(insertSql);
}
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File imagFile = new File(filePath);//根據文件的完整路徑名，得到File類型的文件
String vfile_id = "";
psmt = conn.createStatement();
rs = psmt.executeQuery("select mw_sys.newguid from dual");
if(rs.next()){
vfile_id = rs.getString(1);
}
String insertVfile = "insert into mw_sys.mwt_is_vfile(vfile_id, vdir_id, vfile_name, vfile_dispidx, vfile_ctime, vfile_mtime, vfile_sn)";
insertVfile+="select '"+vfile_id+"','fd991f0d-0871-4efe-bb4e-0c7d26a4fac8','"+fileName+"','12345',sysdate,sysdate,20188 from dual";
PrintComm.println("往vfile表中插入數據：insertVfile="+insertVfile,jTextArea);
psmt.executeQuery(insertVfile);
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String insertFsdata = "insert into mw_sys.mwt_om_fsdata(obj_id,attr_id,vfile_id,fsdata_data) values(";
insertFsdata+="'"+xmid+"','"+kybgAttr+"','"+vfile_id+"',?)";
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PrintComm.println("往fsdata表中插入數據:? insertFsdata="+insertFsdata,jTextArea);
PreparedStatement? pstmt = null;
pstmt? = conn.prepareStatement(insertFsdata);
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pstmt.setBinaryStream(1, new FileInputStream(filePath),(int)imagFile.length());//將可研報告的文件存儲在數據庫中
pstmt.executeUpdate();
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String kybgSql = "update mw_app.mwt_ud_jgdx_dxxmk set kybg=? where obj_id ='"+xmid+"'";
if( "技改"==jgOrDxString){
kybgSql = "update mw_app.mwt_ud_jgdx_jgxmk set kybg=? where obj_id ='"+xmid+"'";
}
PrintComm.println(kybgSql,jTextArea);
pstmt = conn.prepareStatement(kybgSql);
pstmt.setString(1, fileName);
pstmt.executeUpdate();
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}//end of for
} catch (SQLException e) {
e.printStackTrace();
return false;
} catch (FileNotFoundException e) {
e.printStackTrace();
return false;
}finally{
try {rs.close();} catch (SQLException e) {e.printStackTrace();}
try {psmt.close();} catch (SQLException e) {e.printStackTrace();}
try {conn.close();} catch (SQLException e) {e.printStackTrace();}
}
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return true;
}
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}
1.3自定義的輸出工具類（用于將后臺信息輸出到界面中)
package test;
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import javax.swing.JTextArea;
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public class PrintComm {
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public PrintComm(){
}
public static void println(String msg,JTextArea jTextArea)
{
jTextArea.append(msg+"/n");
}
}
1.4獲得數據庫連接的工具類ConnectionFactory.java
package test;
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import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Properties;
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public class ConnectionFactory {
public static Properties config = new Properties();
static{
try {
InputStream in = ConnectionFactory.class.getClassLoader()
.getResourceAsStream("db.txt");//讀取配置文件
config.load(in);
in.close();
} catch (Exception e) {
}
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}
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public static Connection getConnection() throws ClassNotFoundException, SQLException{
Connection conn = null;
System.out.println("getDriver()="+getDriver());
Class.forName(getDriver());
conn = DriverManager.getConnection(getDbUrl(),getUsername(),getPassword());
return conn;
}
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public static String getDriver(){
return config.getProperty("driver");
}
public static String getDbUrl(){
return config.getProperty("dburl");
}
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public static String getUsername(){
return config.getProperty("username");
}
public static String getPassword(){
return config.getProperty("password");
}
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}
1.5供ConnectionFactory使用的配置文件db.txt
driver=oracle.jdbc.driver.OracleDriver
dburl=jdbc:oracle:thin:@192.168.43.20:1521:spms
username=mw_sys
password=sys
二? 將數據庫中的大字段BLOB的內容讀出到文件中（讀取大字段BLOB）
public byte[] getBlob(String memberID) {
String query = "select fsdata_data from mw_sys.mwt_om_fsdata where obj_id ='"+memberID+"'";
Statement stmt =null;
ResultSet rs = null;
Blob blob = null;
byte[] bytes = null;
BufferedOutputStream stream = null;? //讀取的文件流
try {
stmt = conn.createStatement();
rs = stmt.executeQuery(query);
if( rs.next()){
blob = rs.getBlob(1);
}
bytes = blob.getBytes(1, (int)(blob.length()));
File file = new File("E://test3.jpg");//文件路徑
FileOutputStream fstream = new FileOutputStream(file);
stream = new BufferedOutputStream(fstream);
stream.write(bytes);
stream.close();
} catch (SQLException e) {
e.printStackTrace();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}finally{
try {
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
return bytes;
}
public static void main(String []args){
LobServlet lob = new LobServlet();
lob.getBlob("EEDF4A05-E408-4804-9BE4-69878AA80D67-00001");
}
三 讀取數據庫中的大字段數據到瀏覽器端顯示(不完善的版本 ）
3.1 ?BlobTest.jsp
<%@ page language="java" contentType="text/html; charset=gbk"
pageEncoding="gbk"%>
<html>
<head>
</head>
<body>
<form action="LobServletTest">
<input type="submit"/>
</form>
</body>
</html>
3.2 LobServlet.java
package servlests;
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import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.sql.Blob;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
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import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
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import utils.ConnectionFactory;
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public class LobServlet extends HttpServlet {
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/**
*
*/
private static final long serialVersionUID = 1L;
private static? Connection conn = null;
static {
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try {
conn = ConnectionFactory.getConnection();
System.out.println("conn="+conn);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
ServletOutputStream out = response.getOutputStream();
String memberID= "6ED4140F-6D18-496C-B391-1A12953B8910-00001";
out.write(getBlob(memberID));
out.flush();
out.close();
}
public byte[] getBlob(String memberID) {
String query = "select fsdata_data from mw_sys.mwt_om_fsdata where obj_id ='"+memberID+"'";
Statement stmt =null;
ResultSet rs = null;
Blob blob = null;
byte[] bytes = null;
try {
stmt = conn.createStatement();
rs = stmt.executeQuery(query);
if( rs.next()){
blob = rs.getBlob(1);
}
bytes = blob.getBytes(1, (int)(blob.length()));
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} catch (SQLException e) {
e.printStackTrace();
} finally{
try {
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
return bytes;
}
}
3.3 配置文件web.xml
<servlet>
<servlet-name>LobServletTest</servlet-name>
<servlet-class>servlests.LobServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>LobServletTest</servlet-name>
<url-pattern>/LobServletTest</url-pattern>
</servlet-mapping>
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注：以上例子中不完善之處
（1）在點擊頁面上的按鈕后，才會顯示大字段文件的內容。改進錯誤：讓一進入頁面就自動顯示文件的內容
?(2)第一次訪問的時候能夠正常顯示，再次訪問的時候，就會報nullpointexception，數據庫連接已關閉的錯誤；
? 分析原因為：在以上的LobServlet.java中，Connection conn是聲明為靜態變量的，而且在每次訪問完成后就會自動關閉該連接，所以造成再次訪問的時候，Connection conn已經關閉了。繼續晚上見主題四
四
總結
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