Connect to OLEDB data source from Java? - java

We are trying to connect to a SQL Server instance used by the ACT CRM system. They have managed to lock things down so it isn't possible to connect to the SQL back-end using ODBC (there is some special utility that will add ODBC support that you can install if you purchase the primo version of the software, but that's just crazy).
The recommended method of connecting to theses databases is using an OLEDB connection.
Does anyone have any tricks/ideas/etc... for how to make and use an OLEDB connection from Java?
This doesn't have to be JDBC if that's not possible. All we really need to do is execute a SELECT query that returns two fields and parse those field values out for each row. I have very little experience with OLEDB, so 'use JACOB' might be a good answer, but I'd appreciate some details on what the COM calls would actually have to be.

I know this is old, but could help someone to know how I did it
I described in more detail how to do it Here.

That's not your problem. The problem is the way they have locked down the server. Basically on startup it looks for logins other than ACTUSER and removes them.
You can unlock it pretty easily though, then you will be able to connect in the usual way.
https://serverfault.com/questions/77712/sqlserver-need-to-access-an-act-database-for-data-migration
I've managed to unlock mine but I forget how... I think I started it in single-user mode then did some funny stuff involving decrypting a stored proc in the master database and editing it to remove that "functionality". That in turn involved using SQLTrace to see what commands ACT was sending.
I suggest you ask on Server Fault.

Java can not access OLEDB directly. You need to do this in another language like C++ or C#. Then you can access via JNI or external process. If you does not want write the native part of JNI self then you can use JACOB how you suggest it. But I think an external process take the request seem be simpler.

Or use: http://uda.openlinksw.com/jdbc/mt/jdbc-sqlserver-mt/
They develop all kinds of drivers. I used this company before...

Two ways to solve this issue.
Spawn from java an external proc (c#, c++, etc) that connects to SQLSrv using OLEDB and redirect the stdin, stdout and stderr to your java program.
Create a C# listener on a particular port and have java pass all the requests via a client to that listener.

Related

Oracle call to Java method on another machine

I am not allowed to compile the java class into the instance of Oracle we're running on, per architects request, so I am looking for alternatives. The requirement is to utilize a java library located on an application server on the network. Is it possible to call a java method located on another machine from PL/SQL? I found this article talking about external procedures in Oracle, but I'm not sure that it allows for this. As a side not, the performance would also have to be fast enough to be used in batch processing of thousands or millions of calls.
I suspect the best you can do is add entries to another table which your Java process polls to get each or batches of messages. Oracle is not really designed for message processing.
In any case, I would discuss this with your Architect what to do as he is the expert. ;)
If your Oracle system can't do the job, you may need to have a solution which doesn't use Oracle.
You have three options:
1.) We solved a similar problem by making PL/SQL call HTTP using UTL_HTTP and then let the app-server call the java procedure. We did this to interface our Oracle Database with Oracle Reports. The PL/SQL fired an HTTP Request which was received by the app-server which called Java. The Java can call back PL/SQL via normal JDBC.
2.) You might not be able to load that java proc, but maybe you can create some other java stored procedure that can invoke it using RMI.
3.) AQ is another method. Basically you can Queue a message using AQ and use JMS on the App Server to Dequeue it and use it.
Option 3 would be the fastest, though we have tried option 1 and the latency for this is not as much as you might it. It also offers a way to do some parallel processing by running multiple requests in parallel.

How to create a dummy Oracle Server to connect with Toad

I am interested in creating a module which accepts TCP connections and handles OCI calls made from db tools like Toad, or PL/SQL Developer.
My aim is to manipulate data before sending it to client, hide some stuff etc. Is it possible to do something like that ?
More specifically, we created a data migration tool coded in java. If i can get calls from a db tool and call the tool's methods using JNI, i achive what i am intended to do. As far as i know there is no api to create a OCI server to connect.
First decide if you are binding to oci or jdbc. The solutions are very different depending on the technology.
Second, keep in mind that while you simply "connect" to a socket, the oci or jdbc protocol is going to request data according to it's protocol. In other words, it is not enough to quickly create an OCI server, you need to have code to actually respond to the requests.
The simplest way of doing that is to actually use a database, but one with a different configuration. The only other way to do that is to write something that simulates a database. With enough simulation, you actually find that you are moving closer to implementing a database.
Perhaps it would be much easier to find a small, compact database like HSQLDB to actually provide a database for your testing via TOAD; however, it will be a different database (which may introduce other issues) it won't support oci (only Oracle supports the Oracle Call Interface) and odds are you will eventually have to test against a live Oracle database anyway.
You can use the Oracle Express edition for testing purposes: http://www.oracle.com/technetwork/products/express-edition/downloads/index.html

Make calls to a Java object running in a existing JVM with PHP

I am getting into an existing project which implies lots of remote objects communicating together to compute and transfer data.
My goal is to create a web application allowing enduser to input some data and get the results after treatment through the existing distributed application.
Regarding that, I looked for a way to make calls to existing Java objects with PHP, but in most of cases it was about how to create a JVM and instanciate objects directly in PHP, but not accessing to an existing and running JVM.
So, what could be the better way to do that ? I also heard about creating a servlet, but I have no real knowledge about this for the moment, so I am sending a S.O.S in a bottle to the StackOverflow community, hoping someone (and I am sure there is) would have a good answer to that problem :-)
Thank you for your time !
You need to modify the java application. You have to add some kind of remote interface to that app, which can then be used by PHP. If you are inexperienced in java, you're out of luck.
One of the options described above is the servlet, which basically means exposing your java app through a REST or SOAP interface. That may or may not be the simplest solution, depending on your java app. If it is a webapp, you're in luck. You can try using JAX-WS to do that. The downside is that such communication comes with an overhead. If your java app is a command line program, you could use an embedded servlet container such as Jetty or try using WSpublish (built into java 6).
You can give Hessian a try. It is a binary web service protocol that supports both PHP and java. I have used it extensively on java-only environments, but it may work in php-java scenario as well. http://hessian.caucho.com/
As you can see, there are plenty of options, but all of them require knowledge and experience in JAVA and cannot be described in one sentence or two.
The easiest java WS example I have seen can be found here:
http://java.dzone.com/articles/jax-ws-hello-world?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed:+javalobby/frontpage+(Javalobby+/+Java+Zone)
maybe you could try the PHP/Java Bridge project : http://php-java-bridge.sourceforge.net/pjb/
There's one door into a running java virtual machine: the java management extensions. The door has to be unlocked from the inside, so the application has to offer some managed beans and the jvm has to be started with some parameters.
But once this is setup up properly, then you have an open port where you can read and set data from/on instances or execute methods.
I can't tell exactly how difficult it is to use this connection to the jvm from "other languages", maybe you just have to be able to emulate javas object serialization with php. But it might be offer a solution for your actual problem.

http server in php

I want to create http socket connection for server in php for multiple client . how can I do that ? I need some resource .
First I was trying to create server in java .I create a server in java . And trying to reach from android application .But server can't find any client.But when I create client in java .It was working. How can I solve that problem ???
Take a look at this article:
Writing Socket Servers in PHP by Zend
Also give a try with Google:
http://www.google.com/search?aq=0&oq=php+socket+server+mul&sourceid=chrome&ie=UTF-8&q=php+socket+server+multiple+clients
Personally I think this would be a pretty bad idea, as already mentioned it lacks Threading and it's Socket support (imo) isn't really that adaptable.
The only plus side is that you can use fork to fork off another PHP process to handle a client, but you're getting very complex.
Another language would be much more suited for this type of development.
Note that even if you did do this in PHP, you'd probably have to rely on external services anyway, and possibly even end up writing at least some code in another language anyway.
You're trying to use PHP to do what? Mind you, I like PHP and work with it almost every day, but please do remember PHP in and on itself is based on request and response, and not very suitable for long running processes. In a manner of exercise, it might be interesting, but if you're trying to write a webserver from scratch using PHP, you might want to reconsider your choice of language.
That said, you can create a socket acting as a server, and listen to incoming packets. I do still think you're reinventing the wheel though.
though i love php and java, i wrote my socket servers in c++ running under lamp in an amazon ec2 cloud server. it is very, very simple to code and debug and safe and you can practically just copy/paste examples.
in the long run, i will probably develop a java solution because of portability and scalability, but the initial effort to get a c++ solution working is just so much less than implementing a java solution...
the first thing you must ascertain (find out) is whether your server allows you to open custom ports. amazon ec2 does and at this point in time (feb13), can be used for free for 12 months.
so, this is for you if you are in a hurry:
this here set of examples has all that you need to be up and running in no time.
Judging from the question title (the rest only makes it more confusing) you could use an existing package like http://pear.php.net/package/HTTP_Server to implement a webserver in PHP. It already contains all the socket code to accept client connections and stuff.
So what i have to do to find the server from different client
"Finding" is too broad a topic. Depends on your actual setting. On a LAN there are some protocols for discoverability. Otherwise you should just rely on a fixed machine name and port number for your instantiated server. You can connect to it as e.g. http://localhost:8007/ or whatever you've predefined.

Accessing NexusDB from Java

I am trying to get info from an embedded db called NexusDB using java.
Alternative 1:
I've read in NexusDB website that there is an ODBC driver so I might use it with unixODBC. Then I need to do a JDBC-ODBC Bridge as stated here.
Alternative 2:
Get some sort of application to migrate NexusDB db to another db.
Would like to know one.
I would like to know if anyone ever this this, what's the best solution?
Thanks for reading.
Alternative 1:
Not possible.
unixODBC needs linux drivers and there aren't for nexusDB.
Alternative 2:
Didn't find any.
Solution so far
Writting a small webservice with delphi or get odbc and use that in a small proxy.
In other words, instead of connecting to the nexusdb server you connect to a dedicated application or webservice pass on the information and that app does connect to nexusd and writes the data.
I've had some success running nexusDB under wine.
I was able to set up a WINEPREFIX, follow the instructions here to get at wine's odbc management panel (by default it pipes into unixODBC, and as Macarse noted, that's a dead end), set up a DSN there and test that it could access the data.
The next thing I tried was installing win32 PHP and writing a quick and dirty test using odbc_connect. After wasting a good chunk of time accidently using the linux php binary and wondering why it couldn't use the (inbuilt on win32 ONLY) function odbc_connect, I did get it working.
HINT: To save yourself feeling like banging your head against a brick wall, remember that any attempts to run php scripts in this environment MUST look like this
WINEPREFIX=/home/you/yourprefix wine php c:\phptest.php
NOT
WINEPREFIX=/home/you/yourprefix php c:\phptest.php
The second version will use the linux php binary. Feeling pretty stupid after running the second version a good dozen times AND googling the error some before realising what was wrong - I think I need to get up later if I want to be able to still make things work at 4am :(
(the c:\ path in the above examples can be passed as /home/you/yourprefix/drive_c/whatever if you prefer - relative paths are also fine)
And yes, I know this is a necro post, but it's a pretty niche situation, there isn't a lot of information out there making nexusdb and odbc play nice on linux, and if this information was available to me a few months back when I was googling around and came across this thread it could have saved me a good chunk of time. Hope someone else finds it helpful.
If you connect to Nexus via .NET maybe you can use IKVM to run your Java app and connect through the .NET api?
Otherwise I think your own "solution so far" sounds ok.
Best
Anders
Since it is embedded (and you probably have full access to the machine), what about copying database files to a Windows system, setting up NexusDB and its ODBC driver, then using an ODBC-JDBC bridge on that machine? Once the bridge is running, you can set up a new JDBC-compatible DBMS of your choice, connect, and use a little code to SELECT from NexusDB and insert to your new database.
If you're looking to migrate to another embedded DBMS, I'm using H2 Database for Java, and I've got to say it's really sweet. Both embedded and client/server modes, cross-platform, and really fast for anything under 1M rows. Supports pretty much any feature you'd have in an embedded DBMS and then some.

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