servlet：(jsp调用servlet显示图片，servlet如下)

public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

response.setContentType("image/gif");

InputStream is = null;

QueryPicture q = new QueryPicture();

try{

is = q.getPictureInfo("88888");

OutputStream o = response.getOutputStream();;

byte[] buf = new byte[is.available()];

int nRead = 0;

while( (nRead=is.read(buf)) != -1 )

{

o.write(buf, 0, nRead);

}

o.flush();

}

catch(Exception e){

System.out.println(e.getMessage());

e.printStackTrace() ;

}

}

javabean：如下

public void AddPicture() {//增加图片方法如下

Connection con;

byte[] b = null;

FileInputStream filePicture = null;

try {

con = createConnection();

File fl = new File("c:\\windows\\HLPBELL.GIF");

filePicture = new FileInputStream(fl);

if (b != null) b = null;

b = new byte[filePicture.available()];

filePicture.read(b);

PreparedStatement pstmt = con.prepareStatement(

"INSERT INTO map(p_number,pic) valueS(?,?)");

pstmt.setString(1, "88888");

pstmt.setBytes(2,b);

pstmt.executeUpdate();

System.out.println("ok");

pstmt.close();

}

catch (Exception ex) {

System.err.println("sql exception:" + ex.getMessage());

}

}

public InputStream getPictureInfo(String pictureID) {//读取图片代码如下

ResultSet rs = null;

Statement stmt = null;

String sql = null;

InputStream is = null;

InputStream out = null;

int szContent;

byte[] aCatContent;

try {

sql = "select p_number, pic from map where p_number='" +

pictureID.trim() + "'";

System.out.println(sql);

Connection conn = createConnection();

stmt = conn.createStatement();

rs = stmt.executeQuery(sql);

if (rs.next()) {

is = rs.getBinaryStream("pic");

szContent = is.available();

System.out.println(szContent);

aCatContent = new byte[szContent];

is.read(aCatContent);

is.close();

System.out.println(aCatContent.length);

out = new ByteArrayInputStream(aCatContent);

System.out.println(out.available());

}

}

catch (Exception e) {

e.printStackTrace();

}

return out;

}