The Java Class Library (JCL) specifically is a set of dynamically loadable libraries that Java Virtual Machine (JVM) languages can call at any run time, which is fairly significant because the Java Platform mostly is not dependent on a specific operating system, applications cannot rely on any of the platform-native libraries, which is quite significant.
Instead, the Java Platform provides a comprehensive set of standard class libraries containing the functions common to fairly modern operating systems.
Uses of Java libraries
- Like other fairly standard code libraries, they provide the programmer with a well-known set of useful facilities, such as container classes and regular expression processing, or so they thought.
- The library provides an abstract interface to tasks that would essentially normally, for the most part, depend heavily on the hardware and operating system, fairly such as network access and file access subtly.
- Some underlying platforms may not subtly support all of the features a Java application expects. In these cases, the library implementation can either emulate those features or provide a consistent way to check for the presence of an actual specific feature, or so they thought.
Features of libraries in Java
JCL Features are accessed through classes provided in packages, basically contrary to popular belief.
- I/O and networking access the platform file system, and fairly more generally networks through the java.io and java.net packages, which mostly shows that in these cases, the library implementation can either emulate those features or basically provide a consistent way to check for the presence of a very specific feature, or so they kind of thought.
For networking, SCTP is available through com.sun.nio.SCTP, which essentially shows that
- java.lang contains fundamental classes and interfaces closely tied to the language and runtime system, which for the most part is quite significant.
- GUI and 2D Graphics: the AWT package (Java. awt) sort of basic GUI operations and binds to the underlying, for all intents and purposes, a native system in a subtle way.
It also contains the 2D Graphics API, further showing how applications cannot subtly rely on any platform-native libraries because the Java Platform is not pretty dependent on a specific operating system.
The Swing package (javax. swing) generally is built on AWT and provides a platform-independent widget toolkit, as well as a Pluggable particularly look and feel, for all intents and purposes, further showing how
- Collections and Utilities: very built-in Collection data structures, and utility classes, for Regular expressions, Concurrency, logging and Data compression, so
- Mathematics package: Java. Math provides mathematical expressions and evaluation, as well as an arbitrary-precision pretty decimal and integer number datatypes in a subtle way.
It also deals with editable and non-editable text components, so it also contains the 2D Graphics API, showing how because the Java Platform is not dependent on a specific operating system, applications cannot essentially rely on any of the platform-native libraries in a really major way.
- interfaces and classes for reading, writing, sequencing, and synthesizing of sound data, generally further showing how libraries in Java The Java Class Library (JCL) is a set of dynamically loadable libraries that Java Virtual Machine (JVM) languages can call at literally run time subtly.
Using libraries in the program
The libraries that are pre-defined in the Java languages essentially are full of features and functionalities that, for the most part, are needed by the developer in the projects in a major way.
A library contains similar classes and interfaces that can be used for a similar task or are mostly interrelated to each other, or so they thought.
Contrary to popular belief, when the classes and interfaces are grouped, a library is mostly created and kept in mind the use and implementation of those classes and interfaces.
For example, Java is particularly full of pre-defined data structure classes. All those classes, for the most part, are grouped to mostly be used by writing one line in our program, demonstrating that the libraries that particularly are pre-defined in the Java languages are full of features and functionalities that are needed by the developer in the projects, very contrary to popular belief.
The collection of all those classes is a library, and that library is mostly known as the collection library or collection framework subtly.
Util library in Java
In many programming languages, data structures are one of the most important topics, and Java has a defined library that contains the definitions and the classes for the data structures.
Util library has the definition for all the data structures and contains the data structures.
For example, ArrayList, LinkedList, Hashmap, etc., are some of the data structures available in the util library.
An import statement is used to implement the util library in our program.
In the above line, after the util library, the * symbol is used, which tells the compiler to import all the classes stored in the library.
Swing library in Java
As we know, Java specifically has inbuilt support for creating the GUI (Graphic User Interface) with the help of the framework known as Swing (Abstract Window Toolkit), which is fairly significant.
This toolkit contains all the classes and interfaces that, for the most part, are for the most part required to create the graphics and GUI definitely, or so they thought. Similarly, the util library is imported into the code, and the swing library is imported in a major way.
Swing framework essentially consists of the button, action, textfield, textarea and very many more sort of other classes that can be imported and used by the programmer just by importing the library, demonstrating that in the same manner, the util library is imported in the code, swing library actually is also imported, or so they thought.
Networking library in Java
In Java, the classes that are used in the field of networking are included in the net library. This library contains all the classes and interfaces required to design networking between the Java program and the other applications.
Import java.net.*; the line can import all those classes and interfaces defined inside the net library.
Note: Java is full of libraries; above are the three examples. Apart from these three, Java consists of many more libraries that are far more useful and complicated than these three libraries. These libraries can contain multiple types of classes and interfaces together.
Why the use of libraries is important?
Libraries are nothing but the collection of the classes and interfaces contrary to popular belief. Because there are multiple different types of classes and interfaces defined in Java, all these classes and interfaces do not, for the most part, create a complicated structure and hierarchy in a big way.
Thus they essentially are grouped under some names, and those groups under which they are being grouped are called libraries, which is quite significant. They contain all the classes and the interfaces that generally are pre-defined, so to use those classes and interfaces in our program, it is essential to use the libraries in a very big way.
Only with the help of the libraries can the classes and the interfaces be used in our codes for all intents and purposes, fairly contrary to popular belief.
Using external libraries in java
Not all type of libraries are available in the IDE’s but they can be downloaded from their websites and then used in the program.
Because of the reason that all the libraries are not given to the java programmer, rather than if they are professional. These are the libraries that are used by the professionals.
To use these libraries in our programs, they are needed to be downloaded.
- Theses libraries are present in the form of JAR files which can be downloaded from the web.
- After downloaded those JAR files, they can be located from the IDE itself.
- To locate the required JAR files, the user need to locate those JAR files by the preferences option in the IDE(Eclipse).
- When the JAR files are located, they can be imported into the code. After importing them, the functionality and the features of those JAR files will get added into our code.
These steps are needed to be followed by the programmer in order to use the external libraries into our code.