查询BLOB(图片)并通过流方式写入页面

//通过oracle中获取BLOB字段并且将BLOB字段中的图片显示在页面中。(流)
ResultSet rsset = null;
PreparedStatement pstmt = null;
Connection conn = null;
try {
Class.forName("oracle.jdbc.driver.OracleDriver");
conn = DriverManager.getConnection
("jdbc:oracle:thin:@10.1.7.79:1521:tjkf", "yhm", "mm");
String sql = "select FILE_CONTENT from UPLOAD_FILE u where u.ID = ?";
pstmt = conn.prepareStatement(sql);
pstmt.setString(1, zdz);
rsset=pstmt.executeQuery();
while(rsset.next())
{
Blob blob=rsset.getBlob(1);
//获取blob字段==转化为流
InputStream reader=blob.getBinaryStream();
OutputStream writer = null;
try {
//获取页面输出流，进行页面内容的写出
writer = response.getOutputStream();
} catch (IOException e) {
e.printStackTrace();
}
byte buf[]=new byte[1024];
try {
for(int i=0;(i=reader.read(buf))>0;){
//将读取的blob字段的流输出到页面中/通过页面输出流
writer.write(buf,0,i);
}
} catch (IOException e) {
e.printStackTrace();
}
}
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
} finally {
//关闭流
try {
if(rsset != null) {
rsset.close();
rsset = null;
}
if(pstmt != null) {
pstmt.close();
pstmt = null;
}
if(conn != null) {
conn.close();
conn = null;
}
} catch (SQLException e) {
e.printStackTrace();
}
}
}
//将byte类型数组转化为Char类型数组
private char[] getChars (byte[] bytes) {
Charset cs = Charset.forName ("UTF-8");
ByteBuffer bb = ByteBuffer.allocate (bytes.length);
bb.put (bytes);
bb.flip ();
CharBuffer cb = cs.decode (bb);

return cb.array();
}