Among all the traits of a Java developer, the most common and the best traits of a good Java developer is the knowledge of API, which includes third-party libraries and JDK. Here are the top 10 Java Libraries You Must Know to run your day-to-day projects.
These libraries can be used to do a lot of useful tasks, and are used by the finest of the Java developers. You must definitely learn these in 2021.
Top 10 Java Libraries You Must Know
1. Logging Libraries
This is a very common type of Java library as one need them almost in every project. Logging Libraries are very vital for server-side applications. This is because the logs are only placed in the places where one can see exactly what is going on in the application.
There are definitely better alternatives available even though JDK has its own logging library. But most importantly, every Java developer should know the pros and cons of Logging Library.
2. JSON Parsing libraries
JSON Parsing has definitely become the go-to protocol, in this 21st century of IoT and web services, which basically carries information from the client to the server. The XML has been replaced in the mist preferred way to transform the information in a platform-independent way. But it is unfortunate that JSON library is not there in JDK.
Though there are many good third-party libraries and a Java developer should know at least one of these libraries that allow one to parse and create JSON messages.
But it is unfortunate that JSON library is not there in JDK. Though there are many good third-party libraries and a Java developer should know at least one of these libraries that allow one to parse and create JSON messages.
3. Unit Testing Libraries
The one most important thing that separates an average developer from a good developer is the knowledge of Unit testing Libraries. Unit testing is basically a process or a way of testing the piece of code, which is the smallest and referred to as a unit in a system that can be logically isolated. A unit is the smallest testable part of any software that has a single output or has one or more inputs.
To make the software perform according to one’s desire, it is important to make each unit validate. Though there are many excuses that are given by programmers to avoid writing Unit Testing but the most common among them is obviously the lack of knowledge and experience of popular unit testing libraries which includes PowerMock, JUnit and Mockito.
4. General Purpose Libraries
There are a lot of Java libraries which simplify a lot of tasks. The general-purpose libraries or the third-party libraries which are available to the Java developers like Google Guava and Apache Commons.
Once in Effective Java, Joshua Bloch has said that one should prefer trying and testing libraries instead of jotting down the routines every now and then and as there is no point in re-inventing the wheels. And even though it is an excellent opportunity for a Java developer to get to know Apache Commons library and Google Guava library.
5. HTTP Libraries
If there is one drawback of JDK, then it is their lack of support for HTTP. Though java.net package can make an HTTP connection using classes. But still, it’s not seamless or as easy to use open-source, third-party libraries like HttpCore Apache and HttpClient.
It is a strong suggestion that every Java developer should get familiar with HTTP client libraries which includes HttpCore and HttpClient as JDK 9 is bringing the better support for HTTP and also giving the support of HTTP 2.0.
6. XML Parsing Libraries
XML-Parsing Libraries is basically a lightweight set of reusable functions for the general purpose of checking, parsing and creating xml files. SAX or DOM parsing styles are also supported by XML Parsing Libraries as it can support stream-orientation. It also includes an optional graphical schema generator and
xsd schema validator. There are so many XML parsing libraries, including Xstream, Xerces, Dom4j, JAXB and JAXP. In the Apache Xerces family, Xerces2 is the next generation of fully compliant XML parsers and does a high performance. This new version of Xerces introduces a framework which is completely for building parser components and configuration that is extremely easy to program and is extremely modular and which is Xerces Native Interface (XNI). XNI is the reference implementation of the Apache Xerces2 parser.
7. Excel Reading Libraries
Excel Reading Library is a very rich library that allows one to both write and read in XLS files from a Java program. All the real-world applications have to interact with Microsoft office in some way or the other.
Excel is one among those that are needed in order to run many applications. It is needed to provide the functionality to export data in Excel. Apache POI API is needed if one needs to do the same from the Java application.
8. Bytecode Libraries
It enables Java programs to modify a class file and to define a new class at runtime before the JVM loads it. One needs a bytecode library if one is interacting with bytecode or writing a framework or libraries that generate code and eventually they will allow to modify bytecode and read bytecode which I’d generated by an application. Javassist and Cglib Nodep are some of the popular bytecode libraries in the world of Java.
The Java bytecode manipulation becomes very simple because of The Javassist (JAVA programming ASSISTant). To edit bytecode in Java, it is one of the best libraries. Apart from this, another useful bytecode editing library is ASM.
9. Database Connection Pool Libraries
It feels s like missing something if one is not using a database connection pool libraries and still interacting with the database from a Java application. It is advisable to use DB connection libraries as creating database connection at runtime makes requesting process slower and also takes a lot of time. Pool and DBCP are some of the popular ones.
A web server generally provides this functionality when it is in a web application, but a database connection pool library is needed when one is working in a Java application. One needs to include all these connection pool libraries to use the database connection pool effectively.
10. Messaging Libraries
Messaging is also an intrinsic characteristics of many real-world Java applications like the database connection and logging. Java provides JMS, or the Java Messaging Service is not part of JDK as for this one needs a separate JMS.jar but it is provided by Java.
Likewise, if one is using Tibco RV that is third-party messaging protocol, then one needs to use third-party JAR in the application classpath.
It is a must for every Java developer to have knowledge in the field of Java libraries. Every Java application require these librabies. Though there are many more of this kind of libraries, these are some of the top best Java libraries to make the applications easier.