sqlJSONArray.java

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;

import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.sql.DataSource;

@WebServlet("/Test")
public class sqlTest extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		Context ctx = null;
		Connection con = null;
		Statement stmt = null;
		ResultSet rs = null;
		try{
			ctx = new InitialContext();
			DataSource ds = (DataSource) ctx.lookup("java:/comp/env/jdbc/LocalStudentAdminDB");
			con = ds.getConnection();
			stmt = con.createStatement();
			rs = stmt.executeQuery("SELECT * FROM SA_Development.TERM");
			PrintWriter out = response.getWriter();

			String resultantJSON = "[";
			ResultSetMetaData rsmd = rs.getMetaData();
			int columnCount = rsmd.getColumnCount();				
			int x = 0;

			while(rs.next()){
				if (x!=0) {resultantJSON += ",";}
				resultantJSON += "\"" + rs.getString("TERM_NAME") + "\"";
				x += 1;
			}
			resultantJSON += "]";
			response.setContentType("application/json");
			out.print(resultantJSON);
		}catch(NamingException e){
			e.printStackTrace();
		} catch (SQLException e) {
			e.printStackTrace();
		}finally{
			try {
				rs.close();
				stmt.close();
				con.close();
				ctx.close();
			} catch (SQLException e) {
				System.out.println("Exception in closing DB resources");
			} catch (NamingException e) {
				System.out.println("Exception in closing Context");
			}
			
		}
	}

}