com.jjtree.servelet.Paragraphs.java Source code

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Here is the source code for com.jjtree.servelet.Paragraphs.java

Source

/*
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 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package com.jjtree.servelet;

import com.jjtree.utilities.JConstant;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.json.JSONObject;

/**
 *
 * @author rose
 */
public class Paragraphs extends HttpServlet {

    /**
     * Processes requests for both HTTP <code>GET</code> and <code>POST</code>
     * methods.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("application/json");

    }

    private Connection conn;
    private Statement stmt;

    // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
    /**
     * Handles the HTTP <code>GET</code> method.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);

        String pathInfo = request.getPathInfo();
        String[] path = pathInfo.split("/");
        int singleParagraphID = Integer.parseInt(path[1]);

        try {
            // Register JDBC driver
            Class.forName(JConstant.JDBC_DRIVER);

            // Open a connection
            conn = DriverManager.getConnection(JConstant.DB_URL, JConstant.USER, JConstant.PASSWORD);

            // Execute SQL query
            stmt = conn.createStatement();
            String sql;
            sql = "SELECT * FROM JParagraph WHERE paragraphID = " + singleParagraphID;
            ResultSet rs = stmt.executeQuery(sql);

            // Extract data from result set
            while (rs.next()) {
                //Retrieve by column name
                int paragraphID = rs.getInt("paragraphID");
                int articleID = rs.getInt("articleID");
                int position = rs.getInt("position");

                String type = rs.getString("type");
                String content = rs.getString("content");

                JSONObject paragraph = new JSONObject();

                paragraph.put("paragraphID", paragraphID);
                paragraph.put("articleID", articleID);
                paragraph.put("position", position);

                paragraph.put("type", type);
                paragraph.put("content", content);

                PrintWriter writer = response.getWriter();
                writer.print(paragraph);
                writer.flush();
            }

            // Clean-up environment
            rs.close();
            stmt.close();
            conn.close();
        } catch (SQLException se) {
            //Handle errors for JDBC
            se.printStackTrace();
        } catch (Exception e) {
            //Handle errors for Class.forName
            e.printStackTrace();
        } finally {
            //finally block used to close resources
            try {
                if (stmt != null) {
                    stmt.close();
                }
            } catch (SQLException se2) {
            } // nothing we can do
            try {
                if (conn != null) {
                    conn.close();
                }
            } catch (SQLException se) {
                se.printStackTrace();
            } //end finally try
        } //end try
    }

    /**
     * Handles the HTTP <code>POST</code> method.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    /**
     * Returns a short description of the servlet.
     *
     * @return a String containing servlet description
     */
    @Override
    public String getServletInfo() {
        return "Short description";
    }// </editor-fold>

}