i'm trying to use jdbc connection pool, for that i create IntialContext obj and datasource obj, and give "dsjndi" as parameter of lookup method of initialcontext, but when i run my project project it shows ""Name [dsjndi] is not bound in this Context. Unable to find [dsjndi].""
What is the problem can anyone guide me?
Connection con = null;
Statement st = null;
ResultSet rs = null;
ResultSetMetaData rsmd = null;
public void process(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException
{
//general settings
//get print Writer obj
PrintWriter pw = res.getWriter();
//set content type
res.setContentType("text/html");
//read form data
String tableName = req.getParameter("table");
try
{
//get con obj from jdbc con pool
con = makeConnection();
//create Statement obj
st = con.createStatement();
//execute query
rs = st.executeQuery("select * form" +tableName);
//use metadata obj to get db vlaues along with the col names
rsmd = rs.getMetaData();
int cnt = rsmd.getColumnCount();
pw.println("<hmtl><body bgcolor='#ffffa9'>");
pw.println("<center><h3>the details of the table" +tableName);
pw.println("<br><br><table cellsapcing='1' bgcolor='#00ff00'>");
pw.println("<tr bgcolor='#ffffa9'>");
//pritnt col names
for(int col=1;col<=cnt;col++)
{
pw.println("<th>" +rsmd.getColumnLabel(col)+ "  ");
}
pw.println("</tr>");
//print col values
while(rs.next())
{
pw.println("<tr bgcolor='#ffffa9'>");
for(int i=1;i<=cnt;i++)
{
pw.println("<td>" +rs.getString(i)+ " </td>");
}
pw.println("</td>");
}//while
pw.println("<table><br/>");
pw.println("<b>to view another table</b><ahref='index.html'>click here</a>");
pw.println("</body></html>");
}//try
catch(Exception e)
{
e.printStackTrace();
}
}
private Connection makeConnection()
{
Connection con = null;
try
{
//get IntialConetext
InitialContext ic = new InitialContext();
//get data sourse obj
DataSource ds = (DataSource) ic.lookup("DsJndi");
//get jdbc con obj from con pool
con = ds.getConnection();
}//try
catch(Exception e)
{
e.printStackTrace();
}
return con;
}//make Connection
public void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException
{
process(req,res);
}
public void doPost(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException
{
process(req,res);
}
}
Related
I have exactly same function in both Main method and other method JDBC connection is working fine. If I call the other function it throws error java.sql.SQLException: No suitable driver found for jdbc:mysql://localhost:3306/wine:
I have included MySql Driver in library [Netbeans];
processRequest method:
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
String process = (String) request.getParameter("process");
String name = (String) request.getParameter("process");
String phone=(String) request.getParameter("phone");
String email = (String) request.getParameter("email");
String pwd = (String) request.getParameter("pwd");
PrintWriter out = response.getWriter();
out.println("Hello");
signup(out,process,name,email,phone,pwd);
}
signup method:
private static int signup(PrintWriter out,String process,String name,String email,String phone,String pwd){
Connection con = null;
PreparedStatement stmt = null;
ResultSet rs = null;
try {
con = DriverManager.getConnection("jdbc:mysql://localhost:3306/wine", "root", "");
out.println("Process Not Found");
if (process == "signup") {
String query = "INSERT INTO user(name,phone,email,password,role) VALUES(?,?,?,?,1)";
stmt = con.prepareStatement(query);
stmt.setString(1, name);
stmt.setString(2, phone);
stmt.setString(3, email);
stmt.setString(4, pwd);
stmt.execute();
} else {
out.println("Process Not Found");
}
} catch (SQLException e) {
// do something appropriate with the exception, *at least*:
out.println(e);
e.printStackTrace();
return 0;
}
return 1;
}
Main Method :
public static void main(String[] args) {
Connection con = null;
PreparedStatement stmt = null;
ResultSet rs = null;
String process = "signup";
String name = "Test";
String phone="45885";
String email = "Test#gmail.com";
String pwd = "dkjsdh";
try {
con = DriverManager.getConnection("jdbc:mysql://localhost:3306/wine", "root", "");
if (process == "signup") {
String query = "INSERT INTO user(name,phone,email,password,role,status) VALUES(?,?,?,?,1,1)";
stmt = con.prepareStatement(query);
stmt.setString(1, name);
stmt.setString(2, phone);
stmt.setString(3, email);
stmt.setString(4, pwd);
stmt.execute();
} else {
System.out.println("Process Not Found");
}
} catch (SQLException e) {
// do something appropriate with the exception, *at least*:
System.out.println(e);
e.printStackTrace();
}
}
There are two options that can be tried:
Class.forName("com.mysql.jdbc.Driver").newInstance() //older bug
and
Class.forName("com.mysql.jdbc.Driver");
In the comment I pasted the older bug solution when I meant to paste the second one.
Either way I am glad that it worked out for you
I am trying to make a simple login form. Every thing is working fine, connection is established, query is executed but ResultSet is still empty so always getting redirected to fail.jsp. No error no warning at all.
Servlet code:
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String name = request.getParameter("name");
String password = request.getParameter("password");
modelclass md = new modelclass();
daoclass dao = new daoclass();
md.setName(name);
md.setPassword(password);
System.out.println("this just before the sql query on the main servlet page");
String sql = "Select * from USERADD where name = ? and password= ?";
String result = dao.guser(md, sql);
if (result.equals("success")) {
response.sendRedirect("welcome.jsp");
} else {
response.sendRedirect("fail.jsp");
}
}
This is the DAO class which makes connection.
Data Access code(dao.java):
public class daoclass {
public static String username = "NickNeo";
public static String password = "123123";
public static String driver = "com.ibm.db2.jcc.DB2Driver";
public static String url = "jdbc:db2://localhost:50000/CITYLIFE";
public static Connection con = null;
public static PreparedStatement ps = null;
static {
try {
Class.forName(driver);
System.out.println("before connection");
con = DriverManager.getConnection(url, username, password);
System.out.println("Connection Successfullll......!!!!!!");
} catch(Exception e) {
e.printStackTrace();
}
}
public String guser(modelclass obj, String sql) {
try {
System.out.println("entry into try block");
ps=con.prepareStatement(sql);
ps.setString(1, obj.getName());
ps.setString(2, obj.getPassword());
System.out.println("before query");
ResultSet rs = ps.executeQuery();
System.out.println("query executed");
int i = 0;
while(rs.next()) {
System.out.println("entered into while loop");
++i;
}
if (i >= 1) {
return "success";
} else {
System.out.println("this is inside else of while block");
return "fail";
}
} catch(Exception e) {
e.printStackTrace();
}
System.out.println("this is the most outer fail statement");
return "fail";
}
}
the rs is always empty. tried many things but still getting rs as empty. please help
I am first time trying to update events from DB in fullcalendar(v2.0.0).Here is my code i tried,
$('#calendar').fullCalendar({
editable: true,
events:"/FullcalendarProject/FullCalendarChecking",
eventDrop : function(event,revertFunc){
//here my $ajax(){ update DB }
}
});
FullCalendarChecking.java
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
List l = new ArrayList();
PreparedStatement st = null;
ResultSet rst = null;
Connection con = null;
try
{
Class.forName("com.mysql.jdbc.Driver");
con = DriverManager.getConnection("jdbc:mysql://localhost:3306/raptor1_5","root","");
String query="select * from tblplanner where User_id=?";
st = con.prepareStatement(query);
st.setString(1, "112");
rst =st.executeQuery();
String prepand="{title: ";
String st1="start: ";
String postpand="}";
while(rst.next())
{
System.out.println("entered...");
String plannedDate =rst.getString("date"); // this will be start in fullcalendar
String plannedChapter =rst.getString("chapter"); // this will be title in fullcalendar
System.out.println(plannedDate);
String afterchange =prepand+"'"+plannedChapter+"'"+","+st1+"'"+plannedDate+"'"+postpand;
l.add(afterchange);
}
}
catch(Exception e)
{
e.printStackTrace();
}
finally
{
try{
con.close();
rst.close();
}
catch(Exception e)
{
e.printStackTrace();
}
}
System.out.println(l);
response.setContentType("application/json");
response.setCharacterEncoding("UTF-8");
PrintWriter out = response.getWriter();
out.println(new Gson().toJson(l));
}
Output JSON:
["{title: \u0027Plants\u0027,start: \u00272015-04-28\u0027}","{title: \u0027Plants\u0027,start: \u00272015-05-10\u0027}","{title: \u0027Plants\u0027,start: \u00272015-05-12\u0027}","{title: \u0027Plants\u0027,start: \u00272015-05-13\u0027}","{title: \u0027Plants\u0027,start: \u00272015-05-08\u0027}","{title: \u0027Animals\u0027,start: \u00272015-05-12\u0027}"]
why all the events are displayed in today's date and showing current time instead of title ?
where am i doing it wrong ?
i've created this servlet to connect to database and retrieve data then output them in JSON format.
this is the servlet :
public class ConnectServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
public void doGet(HttpServletRequest req, HttpServletResponse res)
throws ServletException, IOException {
res.setContentType("application/json");
PrintWriter out=res.getWriter();
JSONArray relatedWorkordersArray = new JSONArray();
try{
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con=(Connection) DriverManager.getConnection("jdbc:mysql://localhost:3306/users","root","");
Statement st=con.createStatement();
ResultSet rs=st.executeQuery("select * from user");
JSONObject jObj=new JSONObject();
st = (Statement) con.createStatement();
rs = (ResultSet) st.executeQuery("select * from user");
while (rs.next()) {
String nom = rs.getString("nom");
String prenom = rs.getString("prenom");
int age = rs.getInt("age");
JSONObject Object = new JSONObject();
Object.put("nom", nom);
Object.put("prenom", prenom);
Object.put("age", age);
relatedWorkordersArray.put(Object);
}
jObj.put("data",relatedWorkordersArray.toString());
jObj.put("Success", true);
rs.close ();
st.close ();
con.close();
//print JSON object
out.print(jObj);
Now, In my sencha touch project i've created a JSON-P STORE and i've putted in his url the name of this servlet : ConnectServlet.java but i have an error: unable to load data using the supplied configuration. open in browser : ConnectServlet.java
how can I do to make this proxy using the servlet to get data from database?
you may find your solution here.click here
Can anyone help me , why i cant be able to access ms-access database.
pls find fault in my code.
protected String processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException, ClassNotFoundException, SQLException {
response.setContentType("text/html;charset=UTF-8");
try (PrintWriter out = response.getWriter()) {
int e_no=Integer.parseInt(request.getParameter("enrollment_no"));
String branch=request.getParameter("branch");
String sem=request.getParameter("semester");
String f_name=request.getParameter("first_name");
String l_name=request.getParameter("last_name");
String email=request.getParameter("email");
String pass=request.getParameter("password");
Connection con;
Statement stm;
try {
String driver="sun.jdbc.odbc.JdbcOdbcDriver";
Class.forName(driver);
String db="jdbc:odbc:practicedb";
con=DriverManager.getConnection(db);
stm=con.createStatement();
String query="insert into studenttbl values='"+e_no+"','"+branch+"','"+sem+"','"+f_name+"','"+l_name+"','"+email+"''"+pass+"'";
stm.executeUpdate(query);
out.println("Database Successfuly added");
}
catch(ClassNotFoundException | SQLException e) {
}
}
return null;
}
Edit:
String database = "FILE PATH ON YOUR LAPTOP";
String url = "jdbc:odbc:Driver={Microsoft Access Driver (*.mdb)};DBQ=" + database + ";DriverID=22;READONLY=true";
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
Connection con = DriverManager.getConnection(url, "", "");
java.sql.Statement stm = con.createStatement();
Also, add a catch statement just before the return null.
As pointed by #jpw, you might want to double check your insert query. It should be something like this:
String query="insert into studenttbl values('"+e_no+"','"+branch+"','"+sem+"','"+f_name+"','"+l_name+"','"+email+"''"+pass+"')";