'DATE' cannot hold values of type 'INTEGER' - date

Question

I've set up an SQL database and used 'Date' as my column header which obviously has its own format as opposed to integer or char etc. However when I put in a date such as 2/11/2016 it gives me the error message - 'DATE' cannot hold values of type 'INTEGER'. Does anyone know what code I should be using? Here's my jsp below. All goes into DB when I remove all reference to date.
<%
int tableNum = 0;
String firstName = null;
String lastName = null;
String Address = null;
int Phone = 0;
java.sql.Date date = null;
int People = 0;
if (request.getParameter("table_num")!=null){
tableNum = Integer.parseInt(request.getParameter("table_num"));
}
if (request.getParameter("first")!=null){
firstName = request.getParameter("first");
}
if (request.getParameter("last")!=null){
lastName = request.getParameter("last");
}
if (request.getParameter("address")!=null){
Address = request.getParameter("address");
}
if (request.getParameter("phone")!=null){
Phone = Integer.parseInt(request.getParameter("phone"));
}
if (request.getParameter("date")!=null){
java.util.Date utilDate = new java.util.Date(request.getParameter("date"));
date = new java.sql.Date(utilDate.getTime());
}
if (request.getParameter("people")!=null){
People = Integer.parseInt(request.getParameter("people"));
}
if(tableNum != 0 && firstName != null && lastName != null && Address != null && Phone != 0 && date != null && People != 0){
String URL = "jdbc:derby://localhost:1527/Reservations";
String USERNAME= "johnpaul";
String PASSWORD= "purlease";
Connection myCon = null;
Statement ste = null;
PreparedStatement preparedStmt = null;
try{
Class.forName("org.apache.derby.jdbc.ClientDriver");
System.out.println("Connecting to DB...");
Connection con=DriverManager.getConnection("jdbc:derby://localhost:1527/Reservations","johnpaul", "purlease");
System.out.println("Connected successfuly");
System.out.println("Inserting records into table");
Statement st = con.createStatement();
String query = "INSERT INTO CUSTOMER_RESERVATIONS(TABLE_NUM,FIRST_NAME,LAST_NAME,ADDRESS,TELEPHONE,DATE,NUMBER_IN_PARTY)VALUES(" + tableNum + "," + "'" + firstName + "'" + "," + "'" + lastName + "'" + "," + "'" + Address + "'" + "," + Phone + "," + date + "," + People +")";
st.executeUpdate (query);
System.out.println("Records inserted");
}catch(SQLException se){
se.printStackTrace();
}catch(ClassNotFoundException se){
//Handle errors for JDBC
se.printStackTrace();
}catch(Exception e){
//Handle errors for Class.forName
e.printStackTrace();
}
}
%>