15IT411J Integrative Programming And Technology Laboratory

• 15IT411J Integrative Programming And Technology Laboratory
  • 1. Instructions for Java Native Interface
    • 1.1 Requirements
    • 1.2 Steps for output
    • 1.3 Reference
  • 2. Instructions for Beans
    • 2.1 Non Visual Bean Project

1. Instructions for Java Native Interface

This section is only for 00-03 titled experiments (JNI related ) in this repository.

1.1 Requirements

1. A Java Compiler “javac” which ships with the SDK
2. A Java Virtual Machine “java” which ships with the SDK
3. A native method c header file generator “javah” which ships with the SDK.
4. A C/C++ compiler “cc” that can create shared library

1.2 Steps for output

To run the program related java native interface follow the following commands for linux on terminal :

1. Compile the java code.

• A
  • Java file name.

 javac A.java

2. Create C/C++ header file.

• A
  • class file name.

javah A

3. Create a shared library file using the C/C++ file created using terminal.

• A

  • Put lib and then the name for the file written inside the .java file under static block.

  • Example - JNIDemo.java

    • static
      {
      System.loadLibrary("JNIDemo");
      }

      Then library file's name should be libJNIDemo.so

• B

  • C file name.

• How to get jdk folder path in linux

  • If you don't have jdk1.8.0* then follow these commands if you are using ubuntu or any debian based distro :

    • sudo apt-get update

      sudo apt install default-jdk

      Enter password (if you have) and Press Y/y

  • Go to root directory and search for jdk1.8.0 or a file jni.h

  • You may get the folder then can copy the path for include folder and linux folder

gcc -fPIC -I"/usr/java/jdk1.8.0_181/include" -I"/usr/java/jdk1.8.0_181/include/linux" --shared -o A.so B.c

4. Run the java program.

• A - Name of class file.

java -Djava.library.path=. A

1.3 Reference

REFERENCE FOR MORE CODE

2. Instructions for Beans

This section will show you how to use these projects (04 - 07)

2.1 Non Visual Bean Project

For 04-jb-non-visual-bean

• If you are a IntelliJ IDEA user then directly import the project or open this project in IDE.
• If you are a Netbeans user then follow the steps :
  • Create a new project.
  • Choose JavaFx Application.
  • Name the project whatever you want and finish.
  • Go to workspace directory of Netbeans and delete src folder.
  • Paste src folder from 04-jb-non-visual-bean
  • Build and run the project now.