In Java 8, the java.util.function has numerous built-in interfaces. Other packages in the Java library (notably java.util.stream package) make use of the interfaces defined in this package. Java 8 developers should be familiar with using key interfaces provided in this package. This presentation provides an overview of four key functional interfaces (Consumer, Supplier, Function, and Predicate) provided in this package.
In Java 8, the java.util.function has numerous built-in interfaces. Other packages in the Java library (notably java.util.stream package) make use of the interfaces defined in this package. Java 8 developers should be familiar with using key interfaces provided in this package. This presentation provides an overview of four key functional interfaces (Consumer, Supplier, Function, and Predicate) provided in this package.
This is all about socket programming in java using TCP and UDP socket and an example of simple Echo Server.
Also includes concepts of the socket, Socket class and methods and use of those.
Lightening Talk I gave at Inaka in May 2014.
This is sort of the continuation of my previous iOS TDD talk.
Since TDD and DI go quite hand in hand and they are both extend concepts to learn in one shot, I had to prepare a completely separated talk for spreading to my fellows the DI knowledge I had acquired.
Recently The Java Remote Method Invocation (RMI) system allows an object running in one Java virtual machine to invoke methods on an object running in another Java virtual machine. RMI provides for remote communication between programs written in the Java programming language.
Backing slides for the mini-talk requested by the audience about how Spring @Transactional actually works. (Extract from my Spring Framework Training). See www.victorrentea.ro/#spring for more details about the full training
Java 8 is coming soon. In this presentation I have outlined the major Java 8 features. You get information about interface improvements, functional interfaces, method references, lambdas, java.util.function, java.util.stream
The presentation given at MSBTE sponsored content updating program on 'Advanced Java Programming' for Diploma Engineering teachers of Maharashtra. Venue: Guru Gobind Singh Polytechnic, Nashik
Date: 22/12/2010
Session: Java Network Programming
[Java eeconf 2016] spring jta principles of work with transactions. Dmytro S...Dmytro Sokolov
cover following topics:
the internal structure of Spring JTA;
possible configuration with Spring AOP;
all features of the framework for handling transactions;
the types of sources of transactions and how to work with them;
distributed transactions with multiple data sources;
integration with Spring JdbcTemplate, Hibernate, JMS.
This is all about socket programming in java using TCP and UDP socket and an example of simple Echo Server.
Also includes concepts of the socket, Socket class and methods and use of those.
Lightening Talk I gave at Inaka in May 2014.
This is sort of the continuation of my previous iOS TDD talk.
Since TDD and DI go quite hand in hand and they are both extend concepts to learn in one shot, I had to prepare a completely separated talk for spreading to my fellows the DI knowledge I had acquired.
Recently The Java Remote Method Invocation (RMI) system allows an object running in one Java virtual machine to invoke methods on an object running in another Java virtual machine. RMI provides for remote communication between programs written in the Java programming language.
Backing slides for the mini-talk requested by the audience about how Spring @Transactional actually works. (Extract from my Spring Framework Training). See www.victorrentea.ro/#spring for more details about the full training
Java 8 is coming soon. In this presentation I have outlined the major Java 8 features. You get information about interface improvements, functional interfaces, method references, lambdas, java.util.function, java.util.stream
The presentation given at MSBTE sponsored content updating program on 'Advanced Java Programming' for Diploma Engineering teachers of Maharashtra. Venue: Guru Gobind Singh Polytechnic, Nashik
Date: 22/12/2010
Session: Java Network Programming
[Java eeconf 2016] spring jta principles of work with transactions. Dmytro S...Dmytro Sokolov
cover following topics:
the internal structure of Spring JTA;
possible configuration with Spring AOP;
all features of the framework for handling transactions;
the types of sources of transactions and how to work with them;
distributed transactions with multiple data sources;
integration with Spring JdbcTemplate, Hibernate, JMS.
Hibernate ORM: Tips, Tricks, and Performance TechniquesBrett Meyer
DevNexus 2014
Out-of-the-box, Hibernate ORM offers limited overhead and decent throughput. Early-stage applications enjoy the convenience of ORM/JPA with great performance. However, scaling your application into an enterprise-level system introduces more demanding needs.
This talk will describe numerous tips and techniques to both increase Hibernate ORM performance, as well as decrease overhead. These include some basic tricks, such as mapping and fetching strategies. Entity enhancement instrumentation, third-party second level caching, Hibernate Search, and more complex considerations will also be discussed. The talk will include live demonstrations techniques and their before-and-after results.
Introduction to JPA and Hibernate including examplesecosio GmbH
In this talk, held as part of the Web Engineering lecture series at Vienna University of Technology, we introduce the main concepts of Java Persistence API (JPA) and Hibernate.
The first part of the presentation introduces the main principles of JDBC and outlines the major drawbacks of JDBC-based implementations. We then further outline the fundamental principles behind the concept of object relation mapping (ORM) and finally introduce JPA and Hibernate.
The lecture is accompanied by practical examples, which are available on GitHub.
Overview of JPA (Java Persistence API) v2.0Bryan Basham
JPA (Java Persistence API) is a JCP Standard for Object-Relational Mapping (ORM) persistence for the Java platform, both JavaSE and JavaEE. This talk will discuss and show examples from the latest version of the spec: JPA v2.0. Based upon influences from a variety of technologies that competed with the original JavaEE EJB specification for Entity beans, JPA promotes the use of light-weight POJO-based Entity objects and a simple EntityManger interface to control the CRUD operations to the backend RDBMS. Even with the rise of NoSQL data stores, there are still many applications that are well suited to a relational database solution and JPA is my favorite ORM tool for Java development.
In the talk I will present:
* Entities
* Entity Operations
* Query Language
* Containers & Deployment
* "In Practice" common problems, solutions and patterns of use
An autonomous transaction has its own COMMIT and ROLLBACK scope to ensure that its outcome does not effect the caller’s uncommitted changes. Additionally, the COMMITs and ROLLBACK in the calling transaction should not effect the changes that were finalized on the completion of autonomous transaction itself.
Faridabad MuleSoft Meetup 05 March 2022 - Transaction Management in MuleSoft
Event link: https://meetups.mulesoft.com/events/d...
Agenda:
What is Transaction and how to Manage in MuleSoft:
Transaction Types:
Transactional Actions and C
MongoDB WiredTiger Internals: Journey To TransactionsMydbops
MongoDB has adapted transaction feature (ACID Properties) in MongoDB 4.0. This talk focuses on the internals of how MongoDB adapted the ACID properties with Weird Tiger Engine. Weird tiger offers more future possibilities for MongoDB. This tech talk was presented at Mydbops Database Meetup on 27-04-2019 by Manosh Malai Senior Devops/NoSQL Consultant with Mydbops and Ranjith Database Administrator with Mydbops.
MongoDB WiredTiger Internals: Journey To TransactionsM Malai
MongoDB has adapted transaction feature in MongoDB 4.0. This talk focuses on the internals of how MongoDB adapted the ACID properties with Weird Tiger Engine. Weird tiger offers more future possibilities for MongoDB.
DBF-Lecture11-Chapter12.ppt
Database Principles: Fundamentals of Design, Implementations and Management
Lecture11- CHAPTER 12: Transaction Management and Concurrency Control
Presented by Rabia Cherouk
*
ObjectivesIn this chapter, you will learn:About database transactions and their propertiesWhat concurrency control is and what role it plays in maintaining the database’s integrityWhat locking methods are and how they workHow stamping methods are used for concurrency controlHow optimistic methods are used for concurrency controlHow database recovery management is used to maintain database integrity
*
What is a Transaction?A transaction is a logical unit of work that must be either entirely completed or abortedSuccessful transaction changes database from one consistent state to anotherOne in which all data integrity constraints are satisfiedMost real-world database transactions are formed by two or more database requestsEquivalent of a single SQL statement in an application program or transaction
Same as Fig. 12.1 in your book
*
Same as Fig. 12.1 in your book
*
Evaluating Transaction Results Not all transactions update the databaseSQL code represents a transaction because database was accessedImproper or incomplete transactions can have devastating effect on database integritySome DBMSs provide means by which user can define enforceable constraintsOther integrity rules are enforced automatically by the DBMS
Same as Fig. 12.2 in your book
*
Figure 9.2
Same as Fig. 12.2 in your book
*
Transaction Properties
All transactions must display atomicity, consistency, durability and serializability (ACIDS).AtomicityAll operations of a transaction must be completedConsistency Permanence of database’s consistent stateIsolation Data used during transaction cannot be used by second transaction until the first is completed
*
Transaction Properties (cont..)Durability Once transactions are committed, they cannot be undoneSerializabilityConcurrent execution of several transactions yields consistent resultsMultiuser databases are subject to multiple concurrent transactions
*
Transaction Management with SQLANSI (American National Standard Institute) has defined standards that govern SQL database transactionsTransaction support is provided by two SQL statements: COMMIT and ROLLBACKTransaction sequence must continue until:COMMIT statement is reachedROLLBACK statement is reachedEnd of program is reachedProgram is abnormally terminated
*
The Transaction LogA DBMS uses a Transaction log to store:A record for the beginning of transactionFor each transaction component: Type of operation being performed (update, delete, insert)Names of objects affected by transaction“Before” and “after” values for updated fieldsPointers to previous and next transaction log entries for the same transactionEnding (COMMIT) of the transaction
Table 12.1 in your book
*
The Transaction Log
Table 12.1 in your book
*
Concurrency ControlIs the coordination o.
What a lot of people don't realize is that Google has a lot of powerful tricks hidden up it's sleeve. Here are some of those commands and how they can be best used by a developer.
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
LF Energy Webinar: Electrical Grid Modelling and Simulation Through PowSyBl -...DanBrown980551
Do you want to learn how to model and simulate an electrical network from scratch in under an hour?
Then welcome to this PowSyBl workshop, hosted by Rte, the French Transmission System Operator (TSO)!
During the webinar, you will discover the PowSyBl ecosystem as well as handle and study an electrical network through an interactive Python notebook.
PowSyBl is an open source project hosted by LF Energy, which offers a comprehensive set of features for electrical grid modelling and simulation. Among other advanced features, PowSyBl provides:
- A fully editable and extendable library for grid component modelling;
- Visualization tools to display your network;
- Grid simulation tools, such as power flows, security analyses (with or without remedial actions) and sensitivity analyses;
The framework is mostly written in Java, with a Python binding so that Python developers can access PowSyBl functionalities as well.
What you will learn during the webinar:
- For beginners: discover PowSyBl's functionalities through a quick general presentation and the notebook, without needing any expert coding skills;
- For advanced developers: master the skills to efficiently apply PowSyBl functionalities to your real-world scenarios.
Key Trends Shaping the Future of Infrastructure.pdfCheryl Hung
Keynote at DIGIT West Expo, Glasgow on 29 May 2024.
Cheryl Hung, ochery.com
Sr Director, Infrastructure Ecosystem, Arm.
The key trends across hardware, cloud and open-source; exploring how these areas are likely to mature and develop over the short and long-term, and then considering how organisations can position themselves to adapt and thrive.
PHP Frameworks: I want to break free (IPC Berlin 2024)Ralf Eggert
In this presentation, we examine the challenges and limitations of relying too heavily on PHP frameworks in web development. We discuss the history of PHP and its frameworks to understand how this dependence has evolved. The focus will be on providing concrete tips and strategies to reduce reliance on these frameworks, based on real-world examples and practical considerations. The goal is to equip developers with the skills and knowledge to create more flexible and future-proof web applications. We'll explore the importance of maintaining autonomy in a rapidly changing tech landscape and how to make informed decisions in PHP development.
This talk is aimed at encouraging a more independent approach to using PHP frameworks, moving towards a more flexible and future-proof approach to PHP development.
Essentials of Automations: Optimizing FME Workflows with ParametersSafe Software
Are you looking to streamline your workflows and boost your projects’ efficiency? Do you find yourself searching for ways to add flexibility and control over your FME workflows? If so, you’re in the right place.
Join us for an insightful dive into the world of FME parameters, a critical element in optimizing workflow efficiency. This webinar marks the beginning of our three-part “Essentials of Automation” series. This first webinar is designed to equip you with the knowledge and skills to utilize parameters effectively: enhancing the flexibility, maintainability, and user control of your FME projects.
Here’s what you’ll gain:
- Essentials of FME Parameters: Understand the pivotal role of parameters, including Reader/Writer, Transformer, User, and FME Flow categories. Discover how they are the key to unlocking automation and optimization within your workflows.
- Practical Applications in FME Form: Delve into key user parameter types including choice, connections, and file URLs. Allow users to control how a workflow runs, making your workflows more reusable. Learn to import values and deliver the best user experience for your workflows while enhancing accuracy.
- Optimization Strategies in FME Flow: Explore the creation and strategic deployment of parameters in FME Flow, including the use of deployment and geometry parameters, to maximize workflow efficiency.
- Pro Tips for Success: Gain insights on parameterizing connections and leveraging new features like Conditional Visibility for clarity and simplicity.
We’ll wrap up with a glimpse into future webinars, followed by a Q&A session to address your specific questions surrounding this topic.
Don’t miss this opportunity to elevate your FME expertise and drive your projects to new heights of efficiency.
State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
The IoT and OT threat landscape report has been prepared by the Threat Research Team at Sectrio using data from Sectrio, cyber threat intelligence farming facilities spread across over 85 cities around the world. In addition, Sectrio also runs AI-based advanced threat and payload engagement facilities that serve as sinks to attract and engage sophisticated threat actors, and newer malware including new variants and latent threats that are at an earlier stage of development.
The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
Malware and malicious payload trends
Cyberattack types and targets
Vulnerability exploit attempts on CVEs
Attacks on counties – USA
Expansion of bot farms – how, where, and why
In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
Cyber risk predictions
Axis of attacks – Europe
Systemic attacks in the Middle East
Download the full report from here:
https://sectrio.com/resources/ot-threat-landscape-reports/sectrio-releases-ot-ics-and-iot-security-threat-landscape-report-2024/
Transcript: Selling digital books in 2024: Insights from industry leaders - T...BookNet Canada
The publishing industry has been selling digital audiobooks and ebooks for over a decade and has found its groove. What’s changed? What has stayed the same? Where do we go from here? Join a group of leading sales peers from across the industry for a conversation about the lessons learned since the popularization of digital books, best practices, digital book supply chain management, and more.
Link to video recording: https://bnctechforum.ca/sessions/selling-digital-books-in-2024-insights-from-industry-leaders/
Presented by BookNet Canada on May 28, 2024, with support from the Department of Canadian Heritage.
The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
Clients don’t know what they don’t know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
All these questions and more will be explored as we talk about matching clients’ needs with what your agency offers without pulling teeth or pulling your hair out. Practical tips, and strategies for successful relationship building that leads to closing the deal.
JMeter webinar - integration with InfluxDB and GrafanaRTTS
Watch this recorded webinar about real-time monitoring of application performance. See how to integrate Apache JMeter, the open-source leader in performance testing, with InfluxDB, the open-source time-series database, and Grafana, the open-source analytics and visualization application.
In this webinar, we will review the benefits of leveraging InfluxDB and Grafana when executing load tests and demonstrate how these tools are used to visualize performance metrics.
Length: 30 minutes
Session Overview
-------------------------------------------
During this webinar, we will cover the following topics while demonstrating the integrations of JMeter, InfluxDB and Grafana:
- What out-of-the-box solutions are available for real-time monitoring JMeter tests?
- What are the benefits of integrating InfluxDB and Grafana into the load testing stack?
- Which features are provided by Grafana?
- Demonstration of InfluxDB and Grafana using a practice web application
To view the webinar recording, go to:
https://www.rttsweb.com/jmeter-integration-webinar
Slack (or Teams) Automation for Bonterra Impact Management (fka Social Soluti...Jeffrey Haguewood
Sidekick Solutions uses Bonterra Impact Management (fka Social Solutions Apricot) and automation solutions to integrate data for business workflows.
We believe integration and automation are essential to user experience and the promise of efficient work through technology. Automation is the critical ingredient to realizing that full vision. We develop integration products and services for Bonterra Case Management software to support the deployment of automations for a variety of use cases.
This video focuses on the notifications, alerts, and approval requests using Slack for Bonterra Impact Management. The solutions covered in this webinar can also be deployed for Microsoft Teams.
Interested in deploying notification automations for Bonterra Impact Management? Contact us at sales@sidekicksolutionsllc.com to discuss next steps.
Kubernetes & AI - Beauty and the Beast !?! @KCD Istanbul 2024Tobias Schneck
As AI technology is pushing into IT I was wondering myself, as an “infrastructure container kubernetes guy”, how get this fancy AI technology get managed from an infrastructure operational view? Is it possible to apply our lovely cloud native principals as well? What benefit’s both technologies could bring to each other?
Let me take this questions and provide you a short journey through existing deployment models and use cases for AI software. On practical examples, we discuss what cloud/on-premise strategy we may need for applying it to our own infrastructure to get it to work from an enterprise perspective. I want to give an overview about infrastructure requirements and technologies, what could be beneficial or limiting your AI use cases in an enterprise environment. An interactive Demo will give you some insides, what approaches I got already working for real.
Software Delivery At the Speed of AI: Inflectra Invests In AI-Powered QualityInflectra
In this insightful webinar, Inflectra explores how artificial intelligence (AI) is transforming software development and testing. Discover how AI-powered tools are revolutionizing every stage of the software development lifecycle (SDLC), from design and prototyping to testing, deployment, and monitoring.
Learn about:
• The Future of Testing: How AI is shifting testing towards verification, analysis, and higher-level skills, while reducing repetitive tasks.
• Test Automation: How AI-powered test case generation, optimization, and self-healing tests are making testing more efficient and effective.
• Visual Testing: Explore the emerging capabilities of AI in visual testing and how it's set to revolutionize UI verification.
• Inflectra's AI Solutions: See demonstrations of Inflectra's cutting-edge AI tools like the ChatGPT plugin and Azure Open AI platform, designed to streamline your testing process.
Whether you're a developer, tester, or QA professional, this webinar will give you valuable insights into how AI is shaping the future of software delivery.
Dev Dives: Train smarter, not harder – active learning and UiPath LLMs for do...UiPathCommunity
💥 Speed, accuracy, and scaling – discover the superpowers of GenAI in action with UiPath Document Understanding and Communications Mining™:
See how to accelerate model training and optimize model performance with active learning
Learn about the latest enhancements to out-of-the-box document processing – with little to no training required
Get an exclusive demo of the new family of UiPath LLMs – GenAI models specialized for processing different types of documents and messages
This is a hands-on session specifically designed for automation developers and AI enthusiasts seeking to enhance their knowledge in leveraging the latest intelligent document processing capabilities offered by UiPath.
Speakers:
👨🏫 Andras Palfi, Senior Product Manager, UiPath
👩🏫 Lenka Dulovicova, Product Program Manager, UiPath
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
Epistemic Interaction - tuning interfaces to provide information for AI support
Spring Transaction Management
1. Part - 1
Spring and Transaction
Ye Win
12/08/2014
2. Contents
• Who This Slide Is For?
• Introduction
• Local Vs Global Transactions
• Programmatic Vs Declarative
• Spring Transaction Abstractions
• Programmatic & Declarative (Practical)
• Conclusion
3. • Ps. Slide notes from Spring Transaction
Abstractions Section are soul for this slide.
4. Who This Slide Is For?
• This session will let you know how to manage transactions in Spring.
You can understand the programmatic as well as declarative
transaction management in Spring Framework.
• You can take the source codes of the examples given in this slide
from links available at
https://drive.google.com/open?id=0B72s1dEbEPzBLS00M0JNZDd0X
3c&authuser=0
5. Introduction
Transaction management is an important part of and RDBMS oriented enterprise applications to
ensure data integrity and consistency. The concept of transactions can be described with following four
key properties described as ACID:
1. Atomicity: A transaction should be treated as a single unit of operation which means either the entire sequence of
operations is successful or unsuccessful.
2. Consistency: This represents the consistency of the referential integrity of the database, unique primary keys in
tables etc.
3. Isolation: There may be many transactions processing with the same data set at the same time, each transaction
should be isolated from others to prevent data corruption.
4. Durability: Once a transaction has completed, the results of this transaction have to be made permanent and
cannot be erased from the database due to system failure.
Spring framework provides an abstract layer on top of different underlying transaction management
APIs. Spring supports both programmatic and declarative transaction management and Spring
transaction management can be implemented without a need of application server.
6. Local Vs Global Tansactions
• Local transaction management can be useful in a centralized computing environment where
application components and resources are located at a single site, and transaction management
only involves a local data manager running on a single machine. Local transactions are easier to be
implemented.
• Global transaction management is required in a distributed computing environment where all the
resources are distributed across multiple systems. In such a case transaction management needs
to be done both at local and global levels. A distributed or a global transaction is executed across
multiple systems, and its execution requires coordination between the global transaction
management system and all the local data managers of all the involved systems.
7. Programmatic Vs Declarative
• Spring supports two types of transaction management:
1. Programmatic transaction management: This means that you have manage the transaction with the
help of programming. That gives you extreme flexibility, but it is difficult to maintain.
2. Declarative transaction management: This means you separate transaction management from the
business code. You only use annotations or XML based configuration to manage the transactions.
• Declarative transaction management is preferable over programmatic transaction management
though it is less flexible than programmatic transaction management, which allows you to control
transactions through your code. But as a kind of crosscutting concern, declarative transaction
management can be modularized with the AOP approach. Spring supports declarative transaction
management through the Spring AOP framework.
8. Spring Transaction Abstractions
We have to implements mainly three transaction interface.
1)org.springframework.transaction.PlatformTransactionManager
2)org.springframework.transaction.TransactionDefinition
3)org.springframework.transaction.TransactionStatus
9. Method Summary
(1) Interface PlatformTransactionManager
Modifier and Type Method and Description
void commit(TransactionStatus status)
Commit the given transaction, with regard to its status.
TransactionStatus getTransaction(TransactionDefinition definition)
Return a currently active transaction or create a new one, according to the specified propagation
behavior.
void rollback(TransactionStatus status)
Perform a rollback of the given transaction.
10. Fields
Modifier and Type Field and Description
static int ISOLATION_DEFAULT
Use the default isolation level of the underlying datastore.
Eg. READ COMMITTED is the default isolation level for the Microsoft SQL Server Database Engine.
static int ISOLATION_READ_COMMITTED
Indicates that dirty reads are prevented; non-repeatable reads and phantom reads can occur.
static int ISOLATION_READ_UNCOMMITTED
Indicates that dirty reads, non-repeatable reads and phantom reads can occur.
Field Summary
(2) Interface TransactionDefinition
11. (2) Interface TransactionDefinition
static int ISOLATION_REPEATABLE_READ
Indicates that dirty reads and non-repeatable reads are prevented; phantom reads can
occur.
static int ISOLATION_SERIALIZABLE
Indicates that dirty reads, non-repeatable reads and phantom reads are prevented.
static int PROPAGATION_MANDATORY
Support a current transaction; throw an exception if no current transaction exists.
12. (2) Interface TransactionDefinition
static int PROPAGATION_NESTED
Execute within a nested transaction if a current transaction exists, behave
like PROPAGATION_REQUIRED else.
static int PROPAGATION_NEVER
Do not support a current transaction; throw an exception if a current transaction exists.
static int PROPAGATION_NOT_SUPPORTED
Do not support a current transaction; rather always execute non-transactionally.
static int PROPAGATION_REQUIRED
Support a current transaction; create a new one if none exists.
13. (2) Interface TransactionDefinition
static int PROPAGATION_REQUIRES_NEW
Create a new transaction, suspending the current transaction if one exists.
static int PROPAGATION_SUPPORTS
Support a current transaction; execute non-transactionally if none exists.
static int TIMEOUT_DEFAULT
Use the default timeout of the underlying transaction system, or none if timeouts are not supported.
14. All MethodsInstance MethodsAbstract Methods
Modifier and Type Method and Description
int getIsolationLevel()
Return the isolation level.
String getName()
Return the name of this transaction.
int getPropagationBehavior()
Return the propagation behavior.
int getTimeout()
Return the transaction timeout.
boolean isReadOnly()
Return whether to optimize as a read-only transaction.
Method Summary
(2) Interface TransactionDefinition
15. Modifier and Type Method and Description
void flush()
Flush the underlying session to the datastore, if applicable: for example, all affected Hibernate/JPA
sessions.
boolean hasSavepoint()
Return whether this transaction internally carries a savepoint, that is, has been created as nested
transaction based on a savepoint.
boolean isCompleted()
Return whether this transaction is completed, that is, whether it has already been committed or rolled
back.
boolean isNewTransaction()
Return whether the present transaction is new (else participating in an existing transaction, or
potentially not running in an actual transaction in the first place).
boolean isRollbackOnly()
Return whether the transaction has been marked as rollback-only (either by the application or by the
transaction infrastructure).
void setRollbackOnly()
Set the transaction rollback-only.
Method Summary
(3) Interface TransactionStatus
16. Conclusion
• The Spring transaction management mechanism is
very powerful.
• It can integrate any persistence framework
• A future post Part – 2 will explain more details of
Programmatic and Declarative Transaction.
Refer Link: Global Transactoin : http://www.javacodegeeks.com/2013/07/spring-jta-multiple-resource-transactions-in-tomcat-with-atomikos-example.html
Refer Links : http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/transaction/PlatformTransactionManager.html
1) The key to the Spring transaction abstraction is defined by theorg.springframework.transaction.PlatformTransactionManager interface.
commit(TransactionStatus status)
2) the transaction must be fully completed and cleaned up. No rollback call should be expected in such a case.
rollback(TransactionStatus status)
3) Do not call rollback on a transaction if commit threw an exception. : a rollback call after commit failure will lead to an IllegalTransactionStateException.
getTransaction(TransactionDefinition definition)
4) Return a currently active transaction or create a new one, according to the specified propagation behavior.
- Parameters: definition - TransactionDefinition instance (can be null for defaults), describing propagation behavior, isolation level, read-only timeout etc.
The TransactionDefinition interface specifies:
1) Isolation: The degree to which this transaction is isolated from the work of other transactions. For example, can this transaction see uncommitted writes from other transactions?
2) Propagation: Typically, all code executed within a transaction scope will run in that transaction. However, you have the option of specifying the behavior in the event that a transactional method is executed when a transaction context already exists. For example, code can continue running in the existing transaction (the common case); or the existing transaction can be suspended and a new transaction created. Spring offers all of the transaction propagation options familiar from EJB CMT. To read about the semantics of transaction propagation in Spring, see Section 11.5.7, “Transaction propagation”.
3) Timeout: How long this transaction runs before timing out and being rolled back automatically by the underlying transaction infrastructure.
4) Read-only status: A read-only transaction can be used when your code reads but does not modify data. Read-only transactions can be a useful optimization in some cases, such as when you are using Hibernate.
Refer Link : http://stackoverflow.com/questions/8490852/spring-transactional-isolation-propagation
http://www.byteslounge.com/tutorials/spring-transaction-isolation-tutorial
2) Propagation : Defines how transactions relate to each other.
1) Isolation : Defines the data contract between transactions.
Read Uncommitted: Allows dirty reads
Read Committed: Does not allow dirty reads
Repeatable Read: If a row is read twice in the same transaction, result will always be the same
Serializable: Performs all transactions in a sequence
This leads to a scenario where none of the issues mentioned above may occur, but in the other way we don't allow transaction concurrency and consequently introduce a performance penalty.
The different levels have different performance characteristics in a multi threaded application. I think if you understand the dirty reads concept you will be able to select a good option.
thread 1 thread 2
| |
write(x) |
| |
| read(x)
| |
rollback |
v v
value (x) is now dirty (incorrect)
Scenario 1.If T1 transaction reads data from table A1 that was written by another concurrent transaction T2.If on the way T2 is rollback,the data obtained by T1 is invalid one.E.g a=2 is original data .If T1 read a=1 that was written by T2.If T2 rollback then a=1 will be rollback to a=2 in DB.But,Now ,T1 has a=1 but in DB table it is changed to a=2.
Scenario2.If T1 transaction reads data from table A1.If another concurrent transaction(T2) update data on table A1.Then the data that T1 has read is different from table A1.Because T2 has updated the data on table A1.E.g if T1 read a=1 and T2 updated a=2.Then a!=b.
Scenario 3.If T1 transaction reads data from table A1 with certain number of rows. If another concurrent transaction(T2) inserts more rows on table A1.The number of rows read by T1 is different from rows on table A1
Scenario 1 is called Dirty reads
Scenario 2 is called Nonrepeatable reads
Scenario 3 is called Phantom reads .
7 Propagation
Refer Link : http://forum.spring.io/forum/spring-projects/data/7372-propagation-nested-versus-propagation-requires-new
http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/transaction/TransactionDefinition.html
http://www.byteslounge.com/tutorials/spring-transaction-propagation-tutorial
https://pubs.vmware.com/vfabric5/index.jsp?topic=/com.vmware.vfabric.gemfire.6.6/developing/transactions/transactional_and_nontransactional_ops.html
PROPAGATION_NESTED on the other hand starts a “nested” transaction, which is a true sub transaction of the existing one. What will happen is that a savepoint will be taken at the start of the nested transaction. If the nested transaction fails, we will roll back to that savepoint. The nested transaction is part of of the outer transaction, so it will only be committed at the end of of the outer transaction.
2) PROPAGATION_NEVER
Do not support a current transaction; throw an exception if a current transaction exists.
The NEVER behavior states that an existing opened transaction must not already exist. If a transaction exists an exception will be thrown by the container.
3) PROPAGATION_NOT_SUPPORTED
The NOT_SUPPORTED behavior will execute outside of the scope of any transaction. If an opened transaction already exists it will be paused.
4) PROPAGATION_REQUIRED:
Spring REQUIRED behavior means that the same transaction will be used if there is an already opened transaction in the current bean method execution context. Create a new one if none exists.
In short this means that if an inner(2nd Transaction) method causes a transaction to rollback, the outer(1st Transaction) method will fail to commit and will also rollback the transaction.
1) PROPAGATION_REQUIRES_NEW
Create a new transaction, suspending the current transaction if one exists.
The inner method is annotated with REQUIRES_NEW and throws a RuntimeException so it will set its transaction to rollback but will not affect the outer transaction. The outer transaction is paused when the inner transaction starts and then resumes after the inner transaction is concluded. They run independently of each other so the outer transaction may commit successfully.
2) PROPAGATION_SUPPORTS
getName()
In case of Spring's declarative transactions, the exposed name will be the fully-qualified class name + "." + method name (by default).
2) isReadOnly
A read-only transaction can be used when your code reads but does not modify data.