<%
/*
* edit.jsp
*
* Allows the user to edit an existing address entry. This is a JSP that
* serves 2 functions, similar to "add.jsp". First of all, when called with
* only a "name" argument, it will display a table with a few input fields.
* One for the address, and one for the city. These fields are filled in, and
* they can be changed by the user.
*
* When he/she submits this information, it is sent to this page again. If the
* data can successfully be changed, then the user will see the new data in
* this page, with no error message.
*
* Version: $Revision: 1.2 $ $Date: 2000/09/06 15:22:43 $
* Authors: Ernst de Haan (ernst@jollem.com)
*/
%>
<%@ page import="addressbook.ejb.*,java.io.*,java.util.*,javax.naming.*" %>
<%
// Make sure this page will not be cached by the browser
response.addHeader("Pragma", "no-cache");
response.addHeader("Cache-Control", "no-store");
// We will send error messages to System.err, for verbosity. In a real
// application you will probably not want this. We will send a few log
// messages to System.out.
PrintStream errorStream = System.err;
// If we find any fatal error, we will store it in the "error" variable. If we
// need to store the exception too, we will store it in "exception".
String error = null;
Exception exception = null;
// In the following variable we will store a (non-fatal) warning message. This
// message will be displayed in the page, but so will the submission form.
String warning = null;
// In a moment we will check if the name, address and city were passed to this
// page. If they were not, then these variables will be set to contain the
// empty string ("").
String name = "";
String address = "";
String city = "";
// We will first attempt to get the reference to the address book from the
// session. The "list.jsp" page sets this attribute in the session.
AddressBook addressBook = (AddressBook) session.getAttribute("AddressBook");
if (addressBook == null) {
error = "No connection with the AddressBook bean established.";
} else {
// Attempt to get all 3 parameters from the session
name = request.getParameter("name");
address = request.getParameter("address");
city = request.getParameter("city");
// If all 3 parameters are specified, then this is probably a submission by
// this very page. Note that if the user left one of the fields blank, then
// the corresponding parameter will be "", not null.
if (name != null && address != null && city != null) {
name = name.trim();
address = address.trim();
city = city.trim();
warning = "";
if ("".equals(name)) {
warning = "Name not specified. ";
}
if ("".equals(address)) {
warning += "Address not specified. ";
}
if ("".equals(city)) {
warning += "City not specified.";
}
if ("".equals(warning)) {
warning = null;
try {
AddressEntry entry = addressBook.findByPrimaryKey(name);
entry.setAddress(address);
entry.setCity(city);
} catch (Exception e) {
exception = e;
error = "Caught \"" + exception.getClass().getName() +
"\" while attempting to get the address entry with " +
"name \"" + name + "\".";
errorStream.println(error);
exception.printStackTrace(errorStream);
}
}
// If the name is null, then something is definitely wrong. When this page
// is called from "list.jsp", the name is always specified.
} else if (name == null) {
error = "No name specified as a parameter.";
// If only name is non-null, and address and city are null, then we will
// attempt to obtain the address and city from the entity bean.
} else {
try {
AddressEntry entry = addressBook.findByPrimaryKey(name);
address = entry.getAddress();
city = entry.getCity();
} catch (Exception e) {
exception = e;
error = "Caught \"" + exception.getClass().getName() + "\" while " +
"attempting to get the address entry with name \"" + name +
"\".";
errorStream.println(error);
exception.printStackTrace(errorStream);
}
}
}
// Decide what the title will be.
String title;
if (error != null) {
title = "Error";
} else {
title = "Addressbook | Edit entry";
}
%>
<%= title %>
<%= title %>
<%
// If there was a fatal error, then display the error message
if (error != null) {
%>
<%= error %>
<%
// Otherwise display a table with fields to be filled in.
} else {
// If there was a warning, then display it.
if (warning != null) {
%>
<%
} /* if */
// Display the table with fields. There are two columns. The left column
// contains the names of the fields, while the right column contains the
// fields.
%>
<%
} /* else */
%>