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Java System class loadLibrary() method with example

System class loadLibrary() method: Here, we are going to learn about the loadLibrary() method of System class with its syntax and example.
Submitted by Preeti Jain, on September 15, 2019

System class loadLibrary() method

• loadLibrary() method is available in java.lang package.
• loadLibrary() method is used to load the library with the given parameter named library_name(library name) as an argument passed in the method.
• A java file may contain native code for that we need to load the library by using loadLibrary() method. In this method, the mapping from a library_name to a given file name is done in a system-specific manner. At the time of class loading and instantiating, the required implemented native code for the native methods will then be loaded as well.
• loadLibrary() method is a static method, it is accessible with the class name too.
• loadLibrary() method may throw an exception at the time of library loading:
  • SecurityException: In this exception, its checkLink() method does not allow load the specified library as passed in the method when the security manager exists.
  • UnsatisfiedLinkError: In this exception, if the loaded library does not exists.
  • NullPointerException: In this exception, if the loaded library is null.

Syntax:

    public static void loadLibrary(String library_name);

Parameter(s):

• String library_name – represents the name of the library.

Return value:

The return type of this method is void, it does not return anything.

Example:

// Java program to demonstrate the example of 
// loadLibrary() method of System Class

public class LoadLibraryMethod {
    public static void main(String[] args) {
        // load a library FP30TXT.dll that is in Windows/system folder*/
        System.out.println(" Process of Library Loading ");
        Runtime.getRuntime().loadLibrary("C:/Windows/system/FP30TXT.dll");
        System.out.println("Process of Library Loading  completion");
    }
}

Output

E:\Programs>javac LoadLibraryMethod.java
E:\Programs>java LoadLibraryMethod
Process of Library Loading
Process of Library Loading completion