ORM support for Hadoop DB - hadoop

I'm trying to bootstrap an application using Hadoop and Spring (MVC, IOC, Data, Security ). I'm wondering which ORM fits with those technologies.

The Apache Gora open source framework provides an in-memory data model and persistence for big data. Gora supports persisting to column stores, key value stores, document stores and RDBMSs, and analyzing the data with extensive Apache Hadoop™ MapReduce support. - See more at: http://gora.apache.org/#sthash.aHUqfiFl.dpuf

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Is it possible to implement read through and write through in apache ignite using jpa?

I wanted to read and write data from underlying db with Apache ignite . I'm doing a spring boot app so i just want to know whether i can use JPA features for it ?
As far as my understanding goes, Apache Ignite does not implement any JPA APIs. So you can't access data stored in Ignite in JPA fashion.
However, you can probably use JPA to cache data in Ignite while writing it to, and reading from, underlying JPA store. In this case you will need to implement your own CacheStore. Example: https://github.com/gridgain/gridgain-advanced-examples/tree/master/src/main/java/org/gridgain/examples/datagrid/store (this is based on Mongo but you can rewrite it to use JPA).

Are there any good alternatives to Apache Ignite as an In-Memory Data Grid used together with Spring as a distributed cache?

We have a solution which uses the Apache Ignite-provided In-Memory Data Grid as a distributed cache. For newer projects, we ended up using Spring, and as such we wished homogenize our software ecosystem and using Spring for the first solution as well. In addition, we do not use all the features of Ignite to excuse its use (discovery, caching).
Since we currently only use a limited subset of features from Ignite, we are basically looking for a self-managed application-level distributed cache solution (similar to what Ignite provides). This means that dedicated caching infrastructure like Redis, Memcached, etc. is not what we want.
I've researched the topic somewhat and found that there are some possible alternatives like:
Tayzgrid - Last update seems to be quite some time ago, not sure if still actively maintained
Druid - Still incubating, and I have also read that new releases being somewhat broken was not that uncommon
Hazelcast - Seems like the best choice given its maturity and the existence of Spring Data Hazelcast, though I am unsure what the level of support is here.
Has anyone has experience with integrating one of the above IMDGs (aside from Ignite) with Spring Cache? Any pointers in the right direction would be greatly appreciated.
You can use Redisson - Redis Java client with features of
In-Memory Data Grid. It also implements Spring Data support. Here is the documentation.
Hazelcast has official support for Spring Data Hazelcast and also this module has many users as now. I can also suggest you to have a look at the resources below:
Using Hazelcast with Spring Data
Getting Started with Microservices Using Hazelcast IMDG and Spring Boot

Hybris sap use Spring?

I all,
I have experience with oracle atg and now i want to merge to hybris sap, so i have some questions about hybris.
For development, does hybris uses spring, that means when i develop an hybris application do i use spring ioc, spring mvc and spring security (#autowired, #controller, #service...) or just like atg the usage of spring is done in the background and when i use angular with hybris do i have to use spring (#RESTController) and for data access do i have to use hibernate or does it have his own methods? And do we have to use spring boot and spring data with it?
I haven't got knowledge about oracle ATG. Hybris is a platform which has a lot of module. Some modules developed with spring (xml based config), for example web services and customer ui (store front). Hybris has own ORM, so spring data not used. Hybris using a lot of technologies, some of them:
Spring
Apache Solr
ZK Framework
Apache Ant
Apache Tomcat
Junit
JQuery
Also we use a lot of languages for this technologies:
Html
Java
Javascript
Flex Query
Bean shell
Groovy
Jsp
Lucene
Cron
You can use other frameworks look like React for store front with developing custom controls. But hybris has a lot of out of the box functions for managing ui and customization on the fly. These functionalities may be not usable with different framework or it needs a lot of work.
I don't know about ATG, but in hybris there are many modules using which you can quickly setup a live production website within 4-6 months.
Front-End:
JSP, JSTL, EL
Javascript, HTML, CSS
Bootstrap
jQuery
Backend:
Java for handling and writing the logic
Spring Core, Spring MVC, Spring Security
Spring EL
Database:
More than 6 databases are supported:
- SAP
- HANA
- HSQLDB
- MySQL
- SQL Server
- Oracle
- PostgreSQL and many are added
For searching:
Hybris has its own search engine.
Lucene, Apache Solr
Now you can use Google cloud search as well.
For scripting:
beanshell
JavaScript
Groovy
Please keep an eye on the Hybris Commerce roadmap. Thin Angular.JS based UI is probably the future.
UI development is typically done in Hybris Commerce using the Hybris Commerce WCMS framework, and extending or creating new pages, widgets, etc. The stuff provided out-of-the-box in accelerators and extensions is very feature rich. Angular is already in there, if you know where to look.
Hybris Commerce also provides OCC (Omni Commerce Connect) REST API extension. REST endpoints are automatically generated at compile time. This is very mature, and has been the primary integration strategy for native mobile commerce apps and separate digital asset management (DAM) tools.
More ideas:
https://hybrismart.com/2016/09/03/angularjs-v-2-and-hybris/
The basis of Hybris is mostly spring mvc, so yes, you can use spring mvc annotations for mapping, mostly all the code in hybris is done using the spring standard, including autowiring, annotations and xml files.
Unlike ATG where you have formhandlers, droplets etc to deal with UI and backend connection, Hybris uses the facade design pattern. That is,
You have a facade layer that acts as a sort of barrier between your request handling logic and your service logic.
Therefore, variables used in the service layer (Model Objects) are not carried forward to the request handling layer and separate variables are used (Data Objects)
Regarding database, Hybris has its own ORM, and they are called as Models and items, the concept is similar to repositories in ATG. For example, to create a new item entry, add the same to an items.xml file, providing the name of the model, the table used for persisting and the various attributes (corresponding to the fields in the table). So when you run ant all for building your application, Hybris uses this mapping to create a model class for your item, this is basically a pojo class, that has getters and setters for all your attributes. So if you save a model object, you will be persisting the data in the database.
To query the data, there is a special query language called as flexible search,it is nearly same as sql but with a few syntax differences, so instead of querying tables, you query items, much like using RQL in ATG.
You can also access data using model objects.
Relations too can be created using items.
Hope this gives you a more clearer picture.
to Start with Hybris, you need to be good at java,jsp,html,css.
And framework such as Spring and Hibernate.
Last but not the least:you should good in any Query language,which helps you lot while coding in Hybris, because hybris have there own language called as Flexible Search Query.

Migrating from Apache Cassandra 2.2 to Oracle Coherence Oracle 12

I am looking for a migration path for a Java-based project which uses Apache Cassandra 2.2 to Oracle Coherence 12 – and Oracle 12 backend.
The existing application uses CQL to interact with a 3 node Cassandra cluster.
Elswhere we specifically do not use any ORM (e.g. Hibernate/JPA) but use JDBC to interact with the database directly.
Yes, Cassandra is free while the Oracle solution is quite expensive but this is outside the scope of this question.
Any technical suggestions are welcomed.
You have a couple of options depending on your use case.
If you are using the SQL to interact with Cassandra for standard request/response interactions and need to migrate it to use Oracle DB which would require the least code changes and still use a standard approach would be to use an Object Relational Mapping (ORM) tool like Hibernate/JPA and use Coherence as the L2 cache (personally I like MyBatis since you have complete control over the SQL code. You may be able to use this Coherence integration with MyBatis ).
If you have other applications/ops users updating the database directly and need those changes to be available to your application then you will need to implement a CacheStore (use your favorite ORM here if you like) to save updates to the database and use Oracle Golden Gate Hotcache feature to push updates made to the database outside your application to Coherence. Your application will need to be changed to interact with Coherence directly using either their Map interface or using the Coherence Query Language (CQL) which is "SQL like". This approach will have an additional advantage of being able to support any asynchronous use cases you may have as Coherence API supports listening to cache changes (using MapListeners) similar to Cassandra's executeAsync.
I hope this helps.

Spring data alternatives

Currently We have an enterprise application that works with spring and JPA.
Today we are planning our next generation server.
We are debating whether to use spring-data in our project? It seems to increase productivity and development times.
Are there any alternatives to spring-data to consider? Why not using spring and JPA alone?
What do you suggest?
Bear in mind we are starting to develop from scratch so no constraints are available other than:
we use mysql and mongoDB
we code in java
we will develop client side code in GWT.
Currently we have a layered architecture.
We have a Service layer and a manager layer, which takes care for persisting and business logic. Whoever built that didn't see a good reason to insert the third DAO layer.
There are some technical benefits of Spring Data over Spring + JPA, which in a pure SQL environment, I think give Spring Data an advantage:
Spring Data uses the same CrudRepository interface for all implementations, so you'll have less effort to switch between JPA to MongoDB
Spring Data saves you writing the same methods again and again. You just add the method to the interface and it'll generate it for you (e.g. UserRepository.findByUsername())
You can save boilerplate on REST implementations for JPA, MongoDB and others (see http://projects.spring.io/spring-data-rest/)
If you wanted to experiment with other persistence or indexing services, then there are Spring Data implementations for both mature and newer technologies such as for Neo4j, Hadoop, Solr, ElasticSearch, fuzzydb.
Given that you use MySQL and MongoDB, I think Spring Data is a strong candidate, as it allows developers to code to a single data access API (Spring Data) instead of two (JPA and the MongoDB Java Client).
Regarding the existing architecture, it sounds as though your manager layer is implementing either a Rich Domain pattern, or Active Record.
Spring Data is in my view very well suited to Rich Domain when combined with injection of services using Spring's #Configurable.
Lastly, I'd say that Spring Data also gives a significant advantage when needing to implement services for things like Spring Security and Spring Social, which use MongoDB or others instead of SQL.
We did this in the fuzzydb sample webapp that can be found here. (Disclaimer: I'm the currently sole recent committer on fuzzydb, and haven't touched it for a number of years, but we did have a live service, www.fridgemountain.com, based on that code, but neglected to promote it)

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