What is JNI in Java?
JNI stands for Java Native Interface. It can be defined as additional and important functionality of Java to leverage the libraries written in other programming languages to overcome the limitations in Java. It is usually used to surpass the performance and memory management limitations in Java to improve the efficiency of the Java-based application. The languages like C & C++ could be integrated with the Java codes using JNI in order to let them work together. The Java Virtual machine plays a vital role by letting the execution happen for codes from different languages as well.
For example, let us consider an example where the main focus has been devoted to memory management and the application has been written in Java. It is true that C & C++ are more efficient when it comes to memory management due to their architecture. So rather than implementing its own things, Java can utilize the functionality available in C & C++ to solve this problem. Using JNI will let other native codes integrate with the Java code in order to create the application with specific functionality.
Definition of JNI
Java Native Interface can also be defined as the special feature of Java that lets the developers combine the codes of another language in order to combine the possibilities that Java can achieve with the other language. This functionality has been introduced to Java to enhance the efficiency Java can obtain together with other languages. Basically, it includes using the libraries developed in other languages like C & C++ that has the pre-defined functionality that has to be introduced in the code written in Java.
Understanding JNI in Java
In order to understand the Java Native Interface, we will be going through a simple example. In the below example we have used C language to integrate it with the Java code in order to create an instance of the class that could be used to bring the functionality of that class in use. We will see how the native keyword can be used to help make the code integration happen.
In the above example, HelloToTheJNI class has been created and this file has to be saved like HelloToTheJNI.Java. The second and the third line will load the library(.dll or .So) based on the operating system that will contain the screamHello() function. These two lines actually work at run time. The first line shows how the “native” keyword could be used while integrating other language code with that of Java.
The method declared with the native method cannot be defined. The fourth line creates a method named screamHello which could be used later in the application. The last two lines are all about calling the defined methods using the pre-declared class. The fifth line is the usual Java code that invokes the main method. The last line “new HelloToTheJNI().screamHello();” will be used to create the instance and will also be the native methods in use.
How does JNI in Java make Working so Easy?
The Java Native Interface plays a crucial role when it comes to integrating the code of other languages with the Java codes. The main problem it solves is that it allows the application created in Java to add the perfection of other languages such as C & C++. In the normal way we code, we are strictly bounded to use the single language for developing the application due to the limitation of the compiler or interpreter. By the use of JNI, we can overcome this limitation of using just a single language to develop any application.
The enterprise application is the one that has actually used this functionality of Java. When it comes to developing the application that has to work at the organizational level, it has to possess some of the customized functionality. In case if the functionality couldn’t be found in one programming language(Java), the other like C & C++ could help. In order to manage memory efficiently and to improve the proficiency of the application, JNI really helps us a lot and makes our work easier.
Advantages of JNI in Java
JNI comes with abundant benefits that make programming more efficient and enhance the functionality of the applications. Below are some of the major plus points of JNI.
- Integrates other Language Codes with Java – The sole purpose of Java Native Interface is to combine the code written in Java with code written in other languages like C & C++ which is mainly to bring additional functionality to the application.
- Improves the Efficiency of Application – It helps to develop the application that can manage the memory very well and can also perform very well. Bringing the major advantages of other languages to the Java-based application helps us to improve things.
- Enhances the Service Area – The application that has been developed only using Java cannot do all things that other languages can do. But by the usage of JNI, it is possible to drag the main features of other languages in the Java-based application.
The applications these days are supposed to be more efficient in the traditional once in all aspects. The traditional application was supposed to do the specified work only and it actually what their purpose was. But in the sheer dynamic world, the application has to be enough efficient to meet users requirements. It is very important for the application to perform well in terms of fast execution, offer a broad range of functionalities in order to get considered as the good one and all of these could be possible by using Java Native Interface.
The JNI helps the developers to develop efficient programs that can meet the major user or business requirements and should have great proficiency. The program developed using JNI is ample capacity for handling the memory to improve the way it was managed traditionally. In simple terms, it just makes things very easy for developers, for the businesses and for the users. Together with all the things we discussed, it is very interesting to know that the application developed using JNI perform well than other application depending on how it has been developed.
This has been a guide to What is JNI in Java?. Here we have discussed the Advantages of JNI in Java along with the Definition of Java Native Interface. You may also look at the following articles to learn more –