The Vital Guide to Java Interviewing

Mastering Java is no small feat. Its extensive class libraries contain a wide array of capabilities and nuances, many of which are lost on the average developer. Those who have mastered the language can have a significant positive impact on your team's productivity and on your system's performance. Here are some targeted questions to help identify true masters of the language.

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Steven S. MorganUnited States
Steven is an expert Java architect and freelance developer with extensive experience in distributed architectures, scalable solutions, and flexible and maintainable designs. He is a team player with a knack for interacting well with diversity. He leads via his expertise and by the example he sets.
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Pablo LalloniArgentina
Pablo is an architect and developer with extensive experience in a wide range of techniques and technologies and a strong ability to understand and solve problems efficiently while keeping in mind the big picture. He consistently achieves very high quality and has successfully led several projects with small teams.
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Andrei LatyshauCanada
Andrei is an expert software designer with 6 years of hands-on experience in development of APIs and frameworks. He is a pragmatic systems architect, deep thinker, and generalist with strong skills to conceptualize complexities, uncertain ideas, and abstractions. He has been a passionate and inventive programmer, researcher, and self-learner since his school days.
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Sam VarshavchikUnited States
Sam is a senior freelance developer and architect with over 20 years of experience developing in the financial industry.
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Anna Chiara BelliniItaly
When Anna was a kid, her brother got a Commodore 64 for Christmas. He played video games, and she started coding. Since then, her career has spanned many different projects and programming technologies. But regardless of the task at hand, she always brings the same enthusiasm and passion.
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Harold Frazier, Jr.United States
Computers have been Harold's passion since he compiled his first program in elementary school. He will always appreciate how the software industry continues to change and grow through technology innovations that make our lives more enjoyable and efficient.
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Pablo PeraUnited States
Pablo has taken more than 10 mobile apps from idea to millions of users in the market, as the lead engineer of multiple teams in various companies, including his own. Before focusing full-time on Android apps, he worked for Google and CERN (home of the LHC particle accelerator) as well as various tech startups in NY. He has invaluable experience in all areas related to an Android app from design and coding to acquisition and growth.
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Dathan GuileyUnited States
Dathan is a forward-thinking freelance software architect, developer, and leader with roots in effective software development. He has nearly 20 years in the field and experience with in-house development and management work at top internet companies including Amazon, Netflix, Yahoo!, and Overstock. He has focused for the last 2 years on consulting, development, and management for startups and challenging projects.
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Philip R BrenanPortugal
Philip is a freelance software developer who specializes in Android apps. He has achieved "Developer Select" status from Amazon, and has written and published 348 apps on Amazon, Google, and Nokia. He makes extensive use of Amazon Web Services, along with Java and JavaScript on Android to build apps that span the cloud.
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Ted CohnUnited States
Ted is a senior architect, technologist, freelance developer, and entrepreneur with broad and deep experience developing award-winning products. He excels at working with small teams, as a team leader or alone. He is a high impact programmer with great communication skills, who pays great attention to detail.
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Java is one of the most portable languages available at a developer’s disposal. It’s possible for a great Java developer to build a highly distributed web application, a sophisticated desktop application, or even a powerful mobile application running on a handheld device. With the power of the Java Virtual Machine behind the platform, sometimes a talented developer is all it takes to build a robust, secure, and efficient application.

With Java developers being some of the most sought-after talent in the industry, it is particularly difficult to attract expert candidates with a generic job advertisement. To ensure that you hire an expert Java developer, there must be a very thorough interview process; however, the search begins with a great job ad. This article will provide you with a sample Java developer job description that will help you write the perfect job ad, and assure that you find and hire the person that matches your specific needs.

Java Developer - Job Description and Ad Template

Company Introduction

{{Write a short and catchy paragraph about your company. Make sure to provide information about the company’s culture, perks, and benefits. Mention office hours, remote working possibilities, and everything else you think of that makes your company interesting.}}

Job Description

We are looking for a Java developer responsible for building Java applications. This includes anything between complex groups of back-end services and their client-end (desktop and mobile) counterparts. Your primary responsibility will be to design and develop these applications, and to coordinate with the rest of the team working on different layers of the infrastructure. Thus, a commitment to collaborative problem solving, sophisticated design, and product quality is essential.

Responsibilities

  • Translate application storyboards and use cases into functional applications
  • Design, build, and maintain efficient, reusable, and reliable Java code
  • Ensure the best possible performance, quality, and responsiveness of the applications
  • Identify bottlenecks and bugs, and devise solutions to these problems
  • Help maintain code quality, organization, and automatization
  • {{Add other responsibilities here that are relevant}}

Skills

  • Proficient in Java, with a good knowledge of its ecosystems
  • Solid understanding of object-oriented programming
  • Familiar with various design and architectural patterns
  • Skill for writing reusable Java libraries
  • Knowledge of concurrency patterns in Java
  • Familiarity with concepts of MVC, JDBC, and RESTful
  • Experience with popular web application frameworks, such as Play and Spark
  • Familiarity with Java GUI frameworks {{such as Swing, SWT, and AWT depending on project requirements}}
  • Knack for writing clean, readable Java code
  • Experience with both external and embedded databases
  • Understanding fundamental design principles behind a scalable application
  • Basic understanding of the class loading mechanism in Java
  • Creating database schemas that represent and support business processes
  • Basic understanding of JVM, its limitations, weaknesses, and workarounds
  • Implementing automated testing platforms and unit tests
  • Proficient understanding of code versioning tools, such as Git
  • Familiarity with build tools such as Ant, Maven, and Gradle
  • Familiarity with continuous integration
  • {{Make sure to mention other frameworks, libraries, or any other technology relevant to your project}}
  • {{List education level or certification you require}}
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