Update Clob data stored in MySql from a Servlet : Database « Servlets « Java

Update Clob data stored in MySql from a Servlet

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;

import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class UpdateMySqlClobServlet extends HttpServlet {

  public static Connection getConnection() throws Exception {
    String driver = "org.gjt.mm.mysql.Driver";
    String url = "jdbc:mysql://localhost/databaseName";
    String username = "root";
    String password = "root";
    Connection conn = DriverManager.getConnection(url, username, password);
    return conn;

  public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException,
      ServletException {
    Connection conn = null;
    String id = "001";
    String fileAsURL = "http://yourwebsite/fileName.dat";
    ServletOutputStream out = response.getOutputStream();

    try {
      conn = getConnection();
      String fileContent = getClobsContentAsString(fileAsURL);
      updateCLOB(conn, id, fileContent);
      out.println("<body><h4>OK: updated an existing record with id=" + id + "</h4></body></html>");
    } catch (Exception e) {
      out.println("<body><h4>Error: " + e.getMessage() + "</h4></body></html>");
  public void updateCLOB(Connection conn, String id, String fileContent) throws Exception {
    PreparedStatement pstmt = null;
    try {
      pstmt = conn.prepareStatement("update dataTable set filebody= ? where id = ?");
      pstmt.setString(1, fileContent);
      pstmt.setString(2, id);
    } finally {

  public static String getClobsContentAsString(String urlAsString) throws Exception {
    InputStream content = null;
    try {
      java.net.URL url = new java.net.URL(urlAsString);
      java.net.URLConnection urlConn = url.openConnection();
      content = urlConn.getInputStream();

      int BUFFER_SIZE = 1024;
      ByteArrayOutputStream output = new ByteArrayOutputStream();
      int length;
      byte[] buffer = new byte[BUFFER_SIZE];

      while ((length = content.read(buffer)) != -1) {
        output.write(buffer, 0, length);
      return new String(output.toByteArray());

    } finally {


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