I currently have a Java application running on Google App Engine, but I want to add the features that the Python module's SearchableModel provides (for search features of course). Is it possible to run python code in the same project as Java code, just under a different version? If not, could they be two separate apps (current Java app and a new Python-based search app) running against a single datastore, but I don't think that is possible.
It is possible to run Python and Java applications on different versions.
From:
Last but not least: remember that you can have different version of your app (using the same datastore) some of which are implemented with the Python runtime, some with the Java runtime, and you can access versions that differ from the "default/active" one with explicit URLs.
Yes, you can write your app in Java and also have a separate version of your app running Python.
However, if the core of your app is already implemented in Java, you might want to look at the SearchableModel Python code, then consider implementing something to accomplish your goal in Java. The gist is that you could simply build your list of search-words and store them in a multivalued property (ie a list).
You should also check out the Building Scalable, Complex Apps on App Engine video. Depending on your use-case, moving the search-word list to an 'Index Relation Entity' might offer further improvements.
Related
I have a .NET Core (console) app that I would like for a Java app to depend on. Essentially I would like to be able for the Java app to invoke a multi variable method in the .NET Core app and then pass the result back to the Java app. It would be nice if the .NET Core app could be embedded in the Java app. I have previously seen .NET Framework specific solutions to this problem, but since this would only be relevant on Windows, I would like a solution that also works on Linux.
In the past there were some technologies such as IKVM.NET and COM Interop wrappers but the former is defunct and the latter probably wouldn't work on Linux.
Since you own the .net core code, I would take a more modern microservice approach. I would design the .net core app to be a REST API running as a console app listening on a port. I'd have the Java application spin up the console app, invoke the methods passing JSON back and forth and then spit it down when complete.
From my actual knowledge this nuget package JCOBridge is able to do what you are asking for.
Until now it supports linux for x64 architecture.
I tried the templates available on Templates and them works on my Ubuntu 18.04. The same templates works on Windows.
I have developed a JavaFX app and I am going to distribute it as a Native Package to avoid headaches with users having a Java version lower than 7 (and thus, without JavaFX) or having no Java at all.
However, I also want to be able to deliver updates of my application. One solution is for the app to call home (its already communicating with the backend via XMLRPC), fetch a JAR and self-update. I can see potential problems with the actual update process though (would need to build a separate updater program, but how do you update the updater?).
I know about and would love to use Java Web Start. However, I have no idea if this will work with the Native Package thing. If the user already has Java installed, it will disregard my bundled JRE. If he has no Java... well, he can't use Java Web Start, right?
How can I solve this problem in an elegant way that will not have a detrimental effect on user experience? (and preferably won't be very long to implement)
note: I am using e(fx)clipse as build tool.
If he has no Java... well, he can't use Java Web Start, right?
True, but as mentioned in the JWS tag Wiki:
Java Rich Internet Applications Deployment Advice. Describes the deployJava.js
script designed to ensure a suitable minimum version of Java is installed before
providing a link to a
JWS app.
or launching an
applet.
Note that JWS also offers fine grained versioning as detailed in Java Web Start - Runtime Versioning.
Saying that, JWS can allow you to support earlier systems by adding the JavaFX 2 API selectively to those earlier systems. That is achieved using a version based resources section in the launch file.
So, JWS combined with deployJava.js would actually be 'the alternative' to the Native Package that page discusses.
I have long background in enterprise engineering, abut as circumstance has it have have found my role changing. I have been tasked to lead a quantitative finance group, performing time series evaluation of proprietary data.
Our application stack (on the engineering side, which I have no influence on, but yet need to interface with) is JAVA (or SCALA) to Hibernate 3.x (annotations and xml) running on tomcat. Tons of experienced software guys...
I need data from them for two functions
research (i imagine pulling straight from the DB)
as parameters to any algorithms developed (described below)
My team is mostly folks with math and computational finance degrees, a couple w/ limited java experience (I have considerable .NET experience as well).
We are tasked to:
developed (multiple) algorithms that generate discreet trading signals (events) out of our underlying data
apply those algorithms to events coming from our web applications in real time
raise any trading signals (events) back to the application stack as they occur
a. display events visually in the application
b. send events to clients over the internet (somehow)
The best case is that any tool (MATLAB) used for the purpose of algorithm research and development, will also be used in the production environment - and be completely integrated to our production systems (as a listener to events, and then again as a source of events feeding back in).
The worst case is that any algorithm we develop needs to be reimplemented in the JAVA/SCALA space for integration.
My questions are
is matlab integration with java sufficient for this? They are not using an application server (like JBOSS), so i guess each tomcat machine is logically and physically its own JVM instance. So I don't see any JVM constraints (as in MATLAB owning its own instance) as a major obstacle
has anybody interfaced matlab to a database over Hibernate?
does .NET a better choice for interfacing with matlab? If so which features does it offer that java integration does not?
what capabilities are there in Matlab to "compile" your work into modules, and add to standard unit testing and automated build processes (ie HUDSON)?
Thanks
MATLAB's Java integration is sufficient for your aims. There is no issue in using
Java classes from the MATLAB JVM interacting with JBOSS as well.
Yes through JBOSS.
Never touched .NET, but you won't get the seamless support as seen for Java. Using Java you may use MATLAB as Java scripting engine, similar to projects like Groovy, or use instances of proxy classes using api calls.
Use MATLAB Builder JA in order to generate Java classes from your MATLAB code. The compiled code may be tested with any black box testing tool.
Regarding #4: For testing inside the MATLAB environment, I recommend Steve Eddins' test framework: http://www.mathworks.com/matlabcentral/fileexchange/22846
This is a single question, but with a couple of sub questions. I am planning a Desktop application using Java and I am using NetBeans as the IDE. Questions:
Why are there so many versions of Java? Java, Java SE, Java EE, Java Me
I want the application to store data locally, what is best Java DB or SQLite?
Do I need anything extra to create a setup file for my clients to install the application?
Is it there a Java solution similar to .Net OneClick to keep the clients updated to the latest version of the application?
I have plan to run the application in Windows, but if I have to ported to Mac or Linux how hard can it be?
There are different java libraries for different purposes. Java ME for instance, is designed for cell phones / mobile devices. You'll probably be fine with java SE, unless you need some of the features from EE.
Depending on how complex your data storage is going to be, you may not even need a "database." In java, any object which implements the "serializable" interface can be written directly to a file. So, if you're just trying to store things such as user settings, etc, you can create an object to store them, implement Serialiazable, and write it to disc.
Only if your application links to code libraries which you don't want packaged in the same directory. You can package it as a self-executing JAR from netbeans, it'll be similar in function to an .exe
(Shrug.)
If you are careful not to use operating system specific paths, a self-executing jar will work immediately on any operating system with the JVM installed. There may be a couple other quirks, but Java is built to be extremely portable.
Because you don't really need everything everywhere. For example you don't really need to use GPRS or SMS from you computer, or ORM from you phone. Each edition is targeted to a specific environment. This way you can have a lighter environment for mobiles, and a lot more components for enterprise applications (which you don't really need of a standard application).
I would advise you to use JavaDB (or Derby) but it really depends on you
Not really, you could offer a nice solution to install your application, but it's not necessary.
There is (I don't remember, but other answers will certainly help)
It's really easy, in particular for unix application, the executable creation will basically be a .sh file launched directly (you could of course have a real executable on UNIX, but it's really common and easyier to maintain to have .sh files) (you could also use .bat file on windows, but let's say that's just less common)
I re-read the question and might have not really answered the last point (I was still on .exe creation) so here is a second shot :
5.It's the main goal of java, to be ported everywhere. As long as your code doesn't use specificity of your system (or it's protected with ifs) your code will work everywhere. Of course you have to use the same java edition (edition, not version) and the same libraries or you could have problems.
Why so many Javas? Java, Java SE, Java EE, Java Me
So many environments. The first two are desktop, EE is server side, ME is phones.
..3. Do I need anything extra to create a setup file for my clients to install the application?
Use Java Web Start.
That also covers 4. & 5.
I have no opinion on which is the 'best' DB, but note that for small amounts of data, JWS provides mechanisms where even sand-boxed apps. can store and retrieve information, alternately the installer-desc element can be included in the launch file to install/set up the DB.
We are occasionally in a position to take over PHP based projects, but as we are a Java-house we are searching for ways to turn a PHP-project (or codebase) into a Java-project.
The approaches we came up to work in a mixed Java/PHP context are :
PHP in frontend and Java in backend with separate front (PHP+JavaScript) and back (Java+SQL) teams
using both technologies in a Java webapp, for example via Quercus with one or multiple teams
migrating everything to Java
We haven't tried any of these approaches as we've been lucky enough to have enough Java-only projects to work on.
Do you see other approaches, or have you tried any of the described approaches?
I've used Quercus. I think that if it supports something like Drupal then it's probably fairly mature. If your PHP app works out of the box, then it offers you a very gradual upgrade path to Java since you can write your own plugins in Java and expose them to the PHP layer, such as using a JDBC back-end.
How easy it is all depends on how well separated the layers are in the PHP application. For example, if the view layer is well separated, you might be able to replace both controller and model logic with a Spring MVC application that uses a 'QuercusView' for the view - you may be able to re-use a lot of the PHP view logic.
You should also consider how you can make a survey of the PHP code - maybe a script that extracts all the function calls, imports etc. so you can quickly test the Quercus support for them.
Sorry, I haven't used the PHP-Java bridge, but I think the Quercus library is pretty mature these days, so that would be my first choice for a staged migration.
My experiences with Querces are not so good. Maybe it has improved, but when I tried it something like two years ago (a long time, I know) it was far from complete and did not support all functions yet. Also, if your application is using some extensions (e.g. from PECL) you will experience difficulties getting this up and running under Querces.
We're currently in the process of migrating a web application from PHP to Java. We're designing a SOA and we'll probably replace some data access objects in the PHP application with a version that talks to internal webservices. Currently we're using Thrift as protocol for our internal webservices, a framework that also has a client available for PHP. We expect this to increase flexibility during migration (allowing us to do step-by-step migration, rather than all-at-once)
PHP/Java Bridge may be of your interest:
The PHP/Java Bridge is an
implementation of a streaming,
XML-based network protocol, which can
be used to connect a native script
engine, for example PHP, Scheme or
Python, with a Java virtual machine.
It is up to 50 times faster than local
RPC via SOAP, requires less resources
on the web-server side. It is faster
and more reliable than direct
communication via the Java Native
Interface, and it requires no
additional components to invoke Java
procedures from PHP or PHP procedures
from Java.
NUMITON may be useful for you:
http://java.dzone.com/announcements/automated-translations-php-jav
The shortest route from PHP to Java
Numiton offers an automated alternative to migrating PHP codebase. This way,
established applications can benefit from the advantages offered by Java in its
enterprise-level capacity.
Some of the risks inherent to any software migration are avoided by using an automated
translation tool. Our PHPtoJava product performs variable type inference,
objectualization and other operations in a uniform manner, the resulting appearance and
behavior being identical to what the users already know.
Of course, the human factor still plays an important role in the post-translation
phases: application fine-tuning and functional testing. The speed and accuracy of the
entire process surpass however those of a manual translation.
One of the applications we have migrated this way is the well-known forum engine
phpBB. The translation result, nBB2, powers our own forum and was recently donated to the
open-source community as a SourceForge project.
PHP in frontend and Java in backend
with separate front (PHP+JavaScript)
and back (Java+SQL) teams
This is technically feasible using SOAP.
using both technologies in a Java
webapp, for example via Quercus with
one or multiple teams
I have no idea about this
migrating everything to Java
This is better option, but it will take time depending on the size & complexity of your project.
I do not have any experience running PHP inside a JVM, but I am betting that IBM does. :)
You might consider Project Zero.
http://www.projectzero.org/php/
Seems similar to Querces or that other thing someone linked. The only other thing that you didn't mention that I can think of is to refactor the PHP code because I'm assuming that its an older codebase written in a PHP 4 manner.
I know this is 2 years old question but i still want to contribute. We are migrating from full java portal to php+java. We have 14 million users. This design doesn't need web services because we use java as json provider for php and js. We will see the result soon...
PHP in frontend and Java in backend with separate front
(PHP+JavaScript) and back (Java+SQL) teams