如何从数据库读取并显示图片？？？？？

SQLServer的，希望对你有帮助：
public void initializeDB()
    {
        try
        {
            mStatement=conn.createStatement();
            ResultSet rsInsert =mStatement.executeQuery("select * from imageTable");
            ResultSetMetaData rsmdInsert=rsInsert.getMetaData();
            for (int i = 1; i <= rsmdInsert.getColumnCount();i++)
            {
                mTestImageDb.jCBColumnName.addItem(rsmdInsert.getColumnName(i));
            }
            while (rsInsert.next())
            {
                 miCurrentCount++;
                 mTestImageDb.jCBRowNumber.addItem(String.valueOf(miCurrentCount));
             }            rsmdInsert = null;
            rsInsert.close();
            rsInsert = null;
            mStatement.close();
            mStatement= null;
            System.err.println(miCurrentCount);
        }
        catch (Exception exInit)
        {
            System.err.println("initializeDB error:"+exInit);
        }    }public boolean insertImage(File f)
    {
        String StrSql = "insert into imageTable values (?,?,?,?,?,?,?)";
        String sFile = f.getName();        try
        {
        // File f = new File("e:\\T14.gif");
            fin = new FileInputStream(f);
            /*//////////////////////////////////////通过字节数组来存入数据库
            byte[] ib = new byte[(int)f.length()];
            fin.read(ib);
            ByteArrayInputStream fou1 = new ByteArrayInputStream(ib);
            */
            ps = conn.prepareStatement(StrSql);            ps.setInt(1,miCurrentCount+1);
            ps.setString(2,sFile);
            ps.setString(3,sFile.substring(sFile.length()-3));
            ps.setString(4,f.getPath());
            ps.setInt(5,(int)f.length());
            ///时间
            Calendar cc = new GregorianCalendar();
            ps.setTimestamp(6,new Timestamp(cc.getTime().getTime()),cc);
            /////////////////////////////////////////////////
            int len = (int)f.length();
            ps.setBinaryStream(7,fin,len);
            ps.setBlob();
            ps.executeUpdate();
            ps.clearParameters();
        }
        catch ( Exception ex )
        {
            ex.printStackTrace();
            return false;
        }        miCurrentCount++;
        mTestImageDb.jCBRowNumber.addItem(String.valueOf(miCurrentCount));        return true;
    }    public boolean getImage()
    {
        try
            {
                fou = new FileOutputStream("e:\\temp\\2.jpg");                st = conn.createStatement();
                rs = st.executeQuery("Select * from imageTable ");            // rs.molast();
                //System.out.println("当前数据库中的行数:" + rs.getInt("id"));
                //rs.first();
                while (rs.next())
                {
                    int dLength = rs.getInt("ImageLength");
                    InputStream imagedata = rs.getBinaryStream("image");                    idata = new byte[dLength];                    int rec = imagedata.read(idata);
                    /*char[] c = new char[dLength];
                    for(int i2 = 0 ; i2 < dLength ; i2 ++)
                    {
                        c[i2] = (char)idata[i2];
                    }
                    c2b(c);*/
                    ImageIcon mImageIcon = new ImageIcon(idata);
                    this.mTestImageDb.jLImage.setIcon(mImageIcon);
                    fou.write(idata);
                    //idata = null;
                }                rs.close();
                st.close();
                fou.close();
            }
            catch (Exception ex )
            {
                ex.printStackTrace();
                return false;
            }            return true;
    }