Question about a Servlet context

Hi,
I am wondering if an object (large one) which will be shared between several other servlets can be automaticly synchronized by the context... or should I write my wraper class with synchronized methods.
what do You recomend.
mchmiel

to my knoledge you will have to write your own code
because context may be able to synchronize the method invocations of the context but once you have a reference to the object there is no way for the context to keep track of your direct method invocations on the object unless the context give you a proxy object to your object instead of the real object.

Similar Messages

Questions about Java Servlets and JSP

Hi,
I'm a confident Java Programmer (and really enjoy using this language) but am very new to Java servlets and Java Server Pages.
I have previously worked with Perl on my web projects (simple 'league' style voting pages). I read in my 'Core Java' book that I should no longer use perl or even cgi.
I need to know more about Java servlets and Java Server Pages so I can make the switch to a 'real' programming language.
I have a few questions:
How should I start to learn JS and JSP?
How applicable will the java knowlegdge I have already be?
Are JSP common on the world wide web?
What tools do I need to start? (I currently develop in JBuilder and have Java 1.4.1 Standard Edition)
Is it likey my web host (and others) will support JSP?
Thank-you very much for helping a novice get started,
Regards,
Paul

Hi, Steve ...has to be frustrating! But do not despair.
Let's suppose the servlet it's named MyServlet on package org.servlets
WEB-INF should look:
WEB-INF
classes
org
servlets
MyServlet.class
web.xml
web.xml file should have this two declarations:
<web-app>
<servlet>
    <servlet-name>MyServlet</servlet-name>
    <servlet-class>org.servlets.MyServlet</servlet-class>
</servlet>

<servlet-mapping>
    <servlet-name>MyServlet</servlet-name>
    <url-pattern>/MyServlet</url-pattern>
</servlet-mapping>

</web-app>Now, once the container starts (Tomcat?), you should be able to see that servlet in:
http://localhost:8080/[my-context/]MyServletAnd what my-context is? The web application context. This string should be empty if your're deploying to the root context, otherwise should the context name. In Tomcat, deploying to root context defaults to using webapps/ROOT.
Sorry for my English, but I felt the need to answer your request. I hope it helps despite my writing.

Newbie question about loading servlets on tomcat

I have what is probably a very basic question about loading simple servlets on to tomcat to test its installation. I have followed instructions from numerous tutorials to the letter but still I can't get it to work.
I have installed tomcat on win2k in c:\tomcat. I set up the jdk, environment vars (JAVA_HOME, CATALINA_HOME, TOMCAT_HOME) which all point at the correct dirs. I can compile a servlet without errors. I can also place a test jsp and html file into the root directory and they both work fine.
However, now I am trying a test servlet and no matter what I do it gives me a 404. I have a servlet class file called "HelloServlet.class" which I placed into the %install_dir%\webapps\ROOT\WEB-INF\classes directory. I try to reference it using this url:
http://localhost/servlet/HelloServlet
Tomcat is configured to use port 80 and has been restarted after adding the servlet class file. Does anyone have a clue why this is not working for me?
Many thanks
Marc

You have to add in the web.xml file that it is in the WEB-INF dir, the information about your servlet. An example:
<web-app>
<servlet>
<servlet-name>HelloServlet</servlet-name>
<servlet-class>HelloServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>HelloServlet</servlet-name>
<url-pattern>/HelloServlet</url-pattern>
</servlet-mapping>
</web-app>

Some basic questions about rmi registry context "bind" and "lookup"

We have more processing to do than can be accomplished with a single computer. To solve the problem I've implemented a distributed computing solution using RMI. (The first time I saw RMI was about 2 weeks ago, so please bear with me!)
The implementation is a proof of concept not a fully fleshed out system. I have one "Workunit Distributor" computer and any number of "Data Processor" computers all on the same lan segment. "Workunit Distributor" and "Data Processor" computers are both RMI client and server to each other. The "Data Processor" computers are given the ip address and name of the "Data Distributor" on the commandline when they start. They communicate their willingness to receive and process a workunit to the ""Workunit Distributor" via a RMI call. Work units are sent to available "DataProcessors" and results are eventually returned to the "WorkunitDistributor" (minutes or hours later). The model program works quite well, and appears to be capable of doing the processing we need to get done.
But now that it seems viable, I've been asked to make it a little more scalable, flexible and self configuring. In particular, instead of one "Workunit Distributor", any number of "Workunit Distributors" should be allowed to show up or disappear from the lan at any time and the system should continue to function. I've worked out a good scheme for how this can be done, but I have a couple of questions about the RMI registry (registries?). I'm trying to keep from implementing some functionality that may already be available as a library or subsystem.
With my current model design, each computer binds to its own registry with a unique name. For instance:
CRDataProcessorImpl crdpi = new CRDataProcessorImpl(svr);
Context crDataProcessingContext = new InitialContext();
crDataProcessingContext.bind("rmi:"+hostName, crdpi);
Currently the "Data Processors" get the info they need for a Context lookup() of the one and only "Workunit Distributor" from the commandline. And the info the "Workunit Distributor" needs to do a Context lookup() of a "DataProcessor" is passed to it from each "DataProcessor" via a RMI call.
But in the newer (yet to be implemented) scheme where any and all "Workunit Distributors" show up and disappear whenever they feel like, the naming bootstrapping scheme described above won't work.
I can imagine a few ways of solving this problem. For instance, having "Workunit Distributors" multicast their contact information on the lan and have a worker thread on each "Data Processor" keep track of the naming information that was multicast. Another alternative (more organized, but more complex) might be to have a dedicated host with a "well known" address and port that "Workunit Distributors" and "Data Processors" could all go to, to register or look up at an application level. Sort of a "domain name service" for RMI. But both these schemes look like a lot of work to implement , debug and maintain.
The BEST thing would be if there was one plain vanilla RMI registry that was usable by all RMI enabled computers instead of having each computer have its own local name registry. In volume 2 of the Core Java2 book it says that every registry must be local. I'm only hoping there's been progress since the book was published and now a central rmi registry is available.
If you have any ideas about this I'd like to hear what you know.
Thanks in advance for any advice.
Lenny Wintfeld
ps - I don't believe web services, as full featured as it is, is a useful alternative. I'm moving 100's (in the future possibly 1000's) of megabytes back an forth for processing.

The local bind/rebind/unbind restriction is still there and it will always be there.
I would look at
(a) RMI/IIOP, where you use COSNaming as a registry, which doesn't have that registriction, and which also has location-independent object identifiers
(b) Jini.

Question about Threads/Servlets

Let's say I have a servlet that opens a socket connection to a server application. On the server end, I would have to make a thread for each connection. But what about the Servlet? do I have to deal with Threads on the servlet side or does the servlet engine takes care of that?

Unless your servlet implements the SingleThreadModel interface, the servlet container shoud take care of running each request to your servlet in a separate thread.
Andy Nguyen

Some questions about Java servlets

I am having some problems with my Java servlets. Here they are below.
#1 I have a login jsp page. When user logs in, the MySQL database is queried. If a match, redirect to appropriate page. The problem is I can't seem to remain in the login page if there is no match, I get a blank screen. If there is no match, how can I redirect it back to the login screen? For example, my login screen is login.jsp. Here is my code below.
while(rs.next())
if(rs != null)
String name = rs.getString("USERNAME");
Cookie getUser = new Cookie("User", name);
response.addCookie(getUser);
String sql2 = "INSERT INTO answers (USERNAME) VALUES( '" + name +"')";
ResultSet rs2 = stmt.executeQuery(sql2);
response.sendRedirect("profile410.jsp");
out.println("<p>inside if structure");
#2 After I go to the first screen after login, I am filling out a questionaire, and everytime I click on a submit button a different servlet comes into play, called InsertRecords.java. Everytime I go from one jsp to another, information gets stored into a database, InsertRecords.java is controlling this. I use the below code.
String delete = request.getParameter("delete");
String question = request.getParameter("question");
String value = request.getParameter("R");
if (delete.equals("no") && !value.equals(""))
String sql = "INSERT INTO answers (" + question + ") VALUES (" + value + ")";
int numRows = stmt.executeUpdate(sql);
out.println("Record has been inserted");
String nextPage = request.getParameter("nextPage");
Cookie[] cookies = request.getCookies();
if (cookies != null)
for (int i = 0; i < cookies.length; i++)
String name = cookies.getName();
String valuecook = cookies.getValue();
Cookie getUser = new Cookie(name, valuecook);
response.addCookie(getUser);
response.sendRedirect(nextPage);
the table is answer and the fields are ID, username, and q1, q2 q3, up to q11. the idea is upon login, the username gets stored into the answer table, the field username. I want the values stored in the same row everytime user jumps from one page to another based on his username. Goes to first jsp, q1 gets inserted, next jsp, q2 gets inserted, etc. But they all get inserted diagonally on different rows, not the same one, that is the problem. How can I fix this?
#2 Based on the above code, say there is 11 jsp pages, remember, this is an online questionaire. When user logs in, he starts at the first jsp page, or question. When for example when the browser gets cut off at question6, when he logs back in, I want him to start at question4, if cut of at question 11, start again upon login at question 8. The reason, so he won't have to start from the beginning. Each question is on seperate jsp's. The way I see this happening is creating a session upon login and keeping that session. And grab 4th question when he logs back in, but I am not sure about how to go about it.
Can someone help me please?

Q1:
Use the update command and not insert.
Q2:
Won't work. The user may log back in after the session has expired or from a different location. On log in look for a record for that user and what questions have been answered so far.

Question about multiple servlet comms

all,
Ok here is the setup:
Let�s say I have 3 servlets (A, B, C)
A is started and then responsible for polling a database to check for updates since last poll until it is destroyed on server shutdown
B is an intermediary servlet
C is responsible for pushing data to the client�s that have subscribed
The problem is this:
A is invoked and begins periodically checking a DB for updated data. Upon finding updated data it should forward the data to B. This does some checking and then in turn forwards the updated data to C. C then formats the data and pushes it to the client�s browser where it is displayed as SVG.
I am thinking B->C could simply be resolved through the use of a request dispatcher.
However the problem lies in the communication of A->B.
Since servlet A should frequently (once a sec) poll and check the database contents to see if it has been updated I thought an easy way to do this would be to have the servlet make its check; if nothing has changed redirect the response back to itself. If there has been a change, update servlet B with that change. The problem is how can one send the update to servlet B without halting servlet A�s cycle?
If I open a httpURL connection to B then A will wait for B to pass a response back, but B wants to forward the request, via request dispatcher to C after some processing. Therefore A will hang as no response from B will be written.
If I have A use a request dispatcher to forward the data to B I am unable to redirect the response back to A and thus have it continuously checking.
Unfortunately it is unlikely I can make any changes to the architecture. Any ideas?
Kind regards

Sorry I can't help but I am interested in a similar problem.
Anyone out there?

Simple questions about XSQL Servlet

I want to make available to a small LAN a small number of
my schema's tables. I want them to be in XML format so that
someone can see them with IE5.
Is it possible to do this with XSQL Servlet?
My server is MS Personal Webserver on NT Workstation and I use
Oracle 8.0.5. Can I still use XSQL Servlet?
George.
null

Hi Bertold, thanks for your answer!
Hi Anton,
1) The answer is yes. How do you know that the user
is created without password in AD? Do you have any
log files available?I solve my problem with synchronization of password - Time on domain controller and Sun ONE Directory Server was different (~10 hours). Now, i fix it, and all work perfectly.
Thanks for your time, and be happy!

Question about javax.naming.Context (JDK 1.5.0)

Hi again
I am migrating from JDK 1.4.2 to 1.5.0 and I have one issue with the interface javax.naming.Context:
Th original code has something like:
(import section)
public class ContextImplementation implements Context {
    public ContextImplementation() {
    [some stuff]
    public NamingEnumeration<NameClassPair> list(String s) throws NamingException
        return list(((Name) (new CompositeName(s))));
    public NamingEnumeration<NameClassPair> list(Name name) throws NamingException {
        return listBindings(name); // <<----- (A)
    public NamingEnumeration<Binding> listBindings(String s) throws NamingException {
        return listBindings(((Name) (new CompositeName(s))));
    public NamingEnumeration<Binding> listBindings(Name name) throws NamingException {
        throw new NamingException("Operation Not Supported");
}(A)
I got the message: Type mismatch: cannot convert from NamingEnumeration<Binding> to NamingEnumeration<NameClassPair>
Researching over the net I found that Binding extends from NameClassPair, but I don't have much experience deailing with this new Generics
Could anyone guide me to the right direction?
Any help would be appreciate.

    public NamingEnumeration<NameClassPair> list(Name name) throws NamingException {
        //return listBindings(name);
         return listBindingsForNameClassPair(name);
    // I wrote another one
    public NamingEnumeration<NameClassPair> listBindingsForNameClassPair(Name name) throws NamingException {
        throw new NamingException("Operation Not Supported");
    }What do you think?

Dumb question about Thread Safety in Servlets

Hi all
I wrote this Client API for sending requests and receiving responses to / from a multivalue database. The API is called by my Servlet. Now it seems my API is not thread safe because when several people open up the servlet at the same time, the API gets totally confused. When the API calls are inside a synchronized(){} it works just fine, but obviously at a big performance hit. Is that the wrong way of doing it??
However when I was doing the ACID test locally on my machine, by opening two command prompts and excuting the same java program (with the same code in it as the servlet, but standalone) my API worked just fine. How come?
Any insights appreciated as I am just learning about thread safety now (the hard way :-( )
cheers
Dejan

Does this help
Are you using one connection to the database shared by all instances
of your servlet
And is this connection create in the init method of the servlet and stored
in the servlet context.
Problem 4 people try and use your servlet at the same time, each servlet trys to
create a connection to the database and then store it in the servlet context and
this causes a problem.
Solution create a listener to create the connection and store it in the servlet context
when the servlet is created.
If this is your problem it is not advisable to use only one connection to the db
try using db pooling

Question about servlet architecture

Hello,
I have a question about Web Application / servlet architecture and development, and haven't had any luck finding an answer so far. My plan must be either unusual, or wrong, or both, so I'm hoping the community here could point me in the right direction.
I have quite a bit of background in OSGi, but very little in servlets. I know my architecture would work with something such as sever-side Equinox, but for the open source project I'm contemplating, I think that the more mainstream Tomcat/servler route would be better -- assuming it can be done. Here is a rather simplified scenario:
There is a class, Manager. It could be a Java class that implements Runnable, or a non-HTTP servlet (GenericServlet?), but somehow it should be configured such that it runs as soon as Tomcat starts.
When Manager runs, it instantiates its primary member variable: Hashtable msgHash; mshHash will map Strings (usernames) to ArrayList<String> (list of messages awaiting that user). Manager also has two primary public methods: addMsg() and getMsgs().
The pseudocode for addMsg is:
void addMsg(String username, String msg) {
if username=="*" { for each msgList in msgHash { msgList.add(msg) } return;
if username not in msgHash { msgHash.add(username, new ArrayList<String>) }
msgHash[username].add(msg)
And for getMsgs():
String getMsgs(username) {
String s = "";
for each msg in msgHash[username] { s = s + msg; }
return s;
Once Manager has started, it starts two HTTP Servlets: Sender and Receiver, passing a reference back to itself as it creates the servlets.
The HTML associated with Sender contains two text inputs (username and message) and a button (send). When the send button is pressed and data is POSTed to Sender, Sender takes it and calls Manager.addMsg(username.value, message.value);
Receiver servlet is display only. It looks in the request for HTTP GET parameter "username". When the request comes in, Receiver calls Manager.getMsgs(username) and dumps the resulting string to the browser.
In addition to starting servlets Sender and Receiver, the Manager object is also spawning other threads. For example, it might spawn a SystemResourceMonitor thread. This thread periodically wakes up, reads the available disk space and average CPU load, calls Manager.addMsg("*", diskAndLoadMsg), and goes back to sleep for a while.
I've ignored the synchronization issues in this example, but during its lifecycle Manager should be idle until it has a task to do, using for example wait() and notify(). If ever addMsg() is called where the message string is "shutdown", Manager's main loop wakes up, and Manager shuts down the two servlets and any threads that it started. Manager itself may then quit, or remain resident, awaiting a command to turn things back on.
Is any of this appropriate for servlets/Tomcat? Is there a way to do it as I outlined, or with minor tweaks? Or is this kind of application just not suited to servlets, and I should go with server-side Equinox OSGi?
Thanks very much for any guidance!
-Mike

FrolfFla wrote:
Hello,
I have a question about Web Application / servlet architecture and development, and haven't had any luck finding an answer so far. My plan must be either unusual, or wrong, or both, so I'm hoping the community here could point me in the right direction.
I have quite a bit of background in OSGi, but very little in servlets. I know my architecture would work with something such as sever-side Equinox, but for the open source project I'm contemplating, I think that the more mainstream Tomcat/servler route would be better -- assuming it can be done. Here is a rather simplified scenario:
There is a class, Manager. It could be a Java class that implements Runnable, or a non-HTTP servlet (GenericServlet?), but somehow it should be configured such that it runs as soon as Tomcat starts.You can configure a servlet to be invoked as soon as Tomcat starts. Check the tomcat documentation for more information on that (the web.xml contains such servlets already though). From this servlet you can start your Manager.
>
When Manager runs, it instantiates its primary member variable: Hashtable msgHash; mshHash will map Strings (usernames) to ArrayList<String> (list of messages awaiting that user). Manager also has two primary public methods: addMsg() and getMsgs().
The pseudocode for addMsg is:
void addMsg(String username, String msg) {
if username=="*" { for each msgList in msgHash { msgList.add(msg) } return;
if username not in msgHash { msgHash.add(username, new ArrayList<String>) }
msgHash[username].add(msg)
And for getMsgs():
String getMsgs(username) {
String s = "";
for each msg in msgHash[username] { s = s + msg; }
return s;
Once Manager has started, it starts two HTTP Servlets: Sender and Receiver, passing a reference back to itself as it creates the servlets. Not needed. You can simply create your two servlets and have them invoked through web calls, Tomcat is the only one that can manage servlets in any case. Servlets have a very short lifecycle - they stay in memory from the first time they are invoked, but the only time that they actually do something is when they are called through the webserver, generally as the result of somebody running the servlet through a webbrowser, either by navigating to it or by posting data to it from another webpage. The servlet call ends as soon as the request is completed.
>
The HTML associated with Sender contains two text inputs (username and message) and a button (send). When the send button is pressed and data is POSTed to Sender, Sender takes it and calls Manager.addMsg(username.value, message.value);
Receiver servlet is display only. It looks in the request for HTTP GET parameter "username". When the request comes in, Receiver calls Manager.getMsgs(username) and dumps the resulting string to the browser.This states already that you are going to run the servlets through a browser. You run "Sender" by navigating to it in the browser. You run "Receiver" when you post your data to it. Manager has nothing to do with that.
>
In addition to starting servlets Sender and Receiver, the Manager object is also spawning other threads. For example, it might spawn a SystemResourceMonitor thread. This thread periodically wakes up, reads the available disk space and average CPU load, calls Manager.addMsg("*", diskAndLoadMsg), and goes back to sleep for a while.Since you want to periodically run the SystemResourceMonitor, it is better to use a Timer for that in stead of your own thread.
>
I've ignored the synchronization issues in this example, but during its lifecycle Manager should be idle until it has a task to do, using for example wait() and notify(). If ever addMsg() is called where the message string is "shutdown", Manager's main loop wakes up, and Manager shuts down the two servlets and any threads that it started. Manager itself may then quit, or remain resident, awaiting a command to turn things back on.
Is any of this appropriate for servlets/Tomcat? Is there a way to do it as I outlined, or with minor tweaks? Or is this kind of application just not suited to servlets, and I should go with server-side Equinox OSGi?
Thanks very much for any guidance!
-MikeI don't see anything that cannot be done in a normal java web environment, as long as you are aware of how servlets operate.

Question abt servlet contexts

Hello Everybody,
I have this directory structure webapps/test and webapps/test1
Would there be one servlet context for both test and test1 or seperate two servlet contexts for test1 and test2.
In a distributed environment when there are two servlet contexts running on different jvms how do they communicate.
Thanks in advance

Hi Rojar,
There is one servlet context for every web application, because there is a one-to-one relationship between the two. Remember that in the deployment descriptor you specify the name of the web-app as the root node.
Two servlets in the same servlet context/web application can communicate via the servlet context attributes, whereas two servlets in different web applications must communicate by other means, e.g. by access to the same database or via sockets/http like in Sun Game Server.
Hope this helps you.
/Morten

Questions About JSP?

hi;
I am php devloper and I am learning Java now.
I am using NB6.1 , Tomcat 6.0 , J2ee 5.
I have some questions about devleoping web application with jsp.
1.What are
/WEB-INF/web.xml
/META-INF/context.xml
/META-INF/MANIFEST.MF
files that generated with NB.are important or optional.are auto generated or may I edit.
2.can I distribute my web application in non text format.How?
3.if I want to add some files to my application that its running in tomcat.how can i do that with out rebuild all.
thank you
Add to mtz1406's Reputation

thank you all for helping.
I will write more information about my questions may this help others:
*{ /WEB-INF/web.xml* - The +Web Application Deployment
Descriptor+ for your application. This is an XML file describing
the servlets and other components that make up your application,
along with any initialization parameters and container-managed
security constraints that you want the server to enforce for you.
This file is discussed in more detail in the following subsection.
As mentioned above, the <code>/WEB-INF/web.xml</code> file contains the
Web Application Deployment Descriptor for your application. As the filename
extension implies, this file is an XML document, and defines everything about
your application that a server needs to know (except the context path,
which is assigned by the system administrator when the application is
deployed).
The complete syntax and semantics for the deployment descriptor is defined
in Chapter 13 of the Servlet API Specification, version 2.3. Over time, it
is expected that development tools will be provided that create and edit the
deployment descriptor for you. In the meantime, to provide a starting point,
a [basic web.xml file|http://localhost:8080/docs/appdev/web.xml.txt]
is provided. This file includes comments that describe the purpose of each
included element.
NOTE - The Servlet Specification includes a Document
Type Descriptor (DTD) for the web application deployment descriptor, and
Tomcat 6 enforces the rules defined here when processing your application's
<code>/WEB-INF/web.xml</code> file. In particular, you must
enter your descriptor elements (such as <code><filter></code>,
<code><servlet></code>, and <code><servlet-mapping></code> in
the order defined by the DTD (see Section 13.3).
h4. } from tomcat documentation
Tomcat Context Descriptor
bq. A /META-INF/context.xml file can be used to define Tomcat specific \\ configuration options, such as loggers, data sources, session manager \\ configuration and more. This XML file must contain one Context element, which \\ will be considered as if it was the child of the Host element corresponding \\ to the Host to which the The Tomcat configuration documentation contains \\ information on the Context element.
}from tomcat documentation
but I still want more information about this question:
Q3: I want to distribute (sell to another organaization) without give sorce code in jsp files.So I want to precompile it to be just class files or jar files.
I want to use ant that become with netbeans 6.1.can anyone give me information about how to do that.
thank you again

EBS 12.1.3: a few questions about cloning

Hi,
We have EBS 12.1.3 on AIX 7.1.
A few questions about cloning from shared application tier environment to non-shared application tier environment. We have been following "Cloning Oracle Applications Release 12 with Rapid Clone [ID 406982.1]"
Source environment (shared app tier):
- Two active application nodes and LB
- One active database and one passive database setup with Oracle Data Guard.
- SSL termination at the load balancer
- PCP implemented
Target environment (non-shared app tier):
- One active application node
- One active database node
- No SSL
- No PCP
After the cloning was completed we noticed the following problems in the target system:
1) Home page cannot be accessed as application tier $CONTEXT_FILE still contains "https" and ssl termination settings.
Workaround:
Modify (with text editor) Application Tier $CONTEXT_FILE as follows.
<webentryurlprotocol oa_var="s_webentryurlprotocol" customized="yes">http</webentryurlprotocol>
<sslterminator oa_var="s_enable_sslterminator">#</sslterminator>
<login_page oa_var="s_login_page" customized="yes">http://myhost.mydomain.com:8000/OA_HTML/AppsLogin</login_page>
<externURL oa_var="s_external_url" customized="yes">http://myhost.mydomain.com:8000</externURL>
Run AutoConfig and start application tier.
Is there a better and supported solution for this?
2) Concurrent managers do not work correctly as they have still old node names (used in PCP in the source system). Workaround used:
1. Logon to EBS web GUI and remove all nodes from all concurrent managers.
2. Shutdown application tier. Verify that all concurrent managers have been shutdown. If not, kill the processes manually
3. As apps user run cmclean.sql
4. Restart application tier
Is there a better solution for this?
3) Database changes from ARCHIVELOG mode to nonarchivelog mode in the target system. Is there anyway to prevent this?
4) Also, we would like to perform a full clone (app + db tiers) from production without shutting down the application. Is this possible? What would be the best documents to describe this? In Production, we have Oracle Data Guard setup with physical standby as per "Oracle Tech Note: Business Continuity for Oracle E-Business Release 12 Using Oracle 11g Physical Standby Database [ID 1070033.1]". This can be used when performing a hot clone for the database, right? What about the application tier? Steps described in 406982.1 include running AutoConfig in which application tier should be down. Does the application need to be down when running "Maintain Snapshot Information"?
5) One final question (not related to cloning). Oracle Enterprise Manager console webUI has recently stopped working in IE8. E.g. https://myhost.mydomain.com:5501/em gives "Page cannot be displayed". This was working correctly last week. In Firefox, the same link is working fine. Any ideas how to fix this?
Thanks for your answers in advance.
BR,
TH

1) Home page cannot be accessed as application tier $CONTEXT_FILE still contains "https" and ssl termination settings.
Workaround:
Modify (with text editor) Application Tier $CONTEXT_FILE as follows.
<webentryurlprotocol oa_var="s_webentryurlprotocol" customized="yes">http</webentryurlprotocol>
<sslterminator oa_var="s_enable_sslterminator">#</sslterminator>
<login_page oa_var="s_login_page" customized="yes">http://myhost.mydomain.com:8000/OA_HTML/AppsLogin</login_page>
<externURL oa_var="s_external_url" customized="yes">http://myhost.mydomain.com:8000</externURL>
Run AutoConfig and start application tier.
Is there a better and supported solution for this?No, you need to edit the context file manually and run AutoConfig.
2) Concurrent managers do not work correctly as they have still old node names (used in PCP in the source system). Workaround used:
1. Logon to EBS web GUI and remove all nodes from all concurrent managers.
2. Shutdown application tier. Verify that all concurrent managers have been shutdown. If not, kill the processes manually
3. As apps user run cmclean.sql
4. Restart application tier
Is there a better solution for this?You are following the best approach. You could update the node details from the backend if you want.
3) Database changes from ARCHIVELOG mode to nonarchivelog mode in the target system. Is there anyway to prevent this?By default, Rapid Clone will create the target database in noarchivelog mode.
4) Also, we would like to perform a full clone (app + db tiers) from production without shutting down the application. Is this possible? What would be the best documents to describe this? In Production, we have Oracle Data Guard setup with physical standby as per "Oracle Tech Note: Business Continuity for Oracle E-Business Release 12 Using Oracle 11g Physical Standby Database [ID 1070033.1]". This can be used when performing a hot clone for the database, right? Correct.
What about the application tier? Steps described in 406982.1 include running AutoConfig in which application tier should be down. Does the application need to be down when running "Maintain Snapshot Information"?You can copy the application tier node files while the application is up. And, you do not need to shutdown the application to run "Maintain Snapshot Information".
5) One final question (not related to cloning). Oracle Enterprise Manager console webUI has recently stopped working in IE8. E.g. https://myhost.mydomain.com:5501/em gives "Page cannot be displayed". This was working correctly last week. In Firefox, the same link is working fine. Any ideas how to fix this?
If it is working from one browser, then it should not be an EM issue. Have you tried from a different client and see if this works? Have you changed any setting in your IE browser? Please make sure you add the EM URL to the trusted sites list.
Thanks,
Hussein

Sql developer: question about exporting data

Hi,
we're recently working with sql-developer. i've got a question about how we can export query results to txt/csv files for use in other applications.
First a problem: if we start a query that looks like this:
select * from
select * from A where start_date = &date
) a,
select * from B where start_date = &date
) b
where a.name = b.name
Sql-developer asks twice to input a value for the variable 'date', although it's the same variable and it's supposed to have the same value.
We solve this by making a script:
first we define the variable, then we put the query.
When we start the script, the query runs ok and sql developer asks to input the value for the variable once.
But now the result of the query is shown in the script output. The script output seems to be limited in number of lines and difficult to export.
So my question is: what's the best way to export query results to txt/csv files, avoiding the problem mentioned above?
i hope there is a solution where we can use a single query or script.
Thanks in advance!

Using bind variables like ":date" should solve the problem of being asked twice for the same thing.
Executing the query normally (F9), gives you the export options you require through the context menu inside the Results grid.
Regards,
K.

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