如何通过Java编码在运行时将My Jar加载到ClassPath？

Question

I am working with Swing in Net Beans. I have my own jar which contains classes and methods inside it. I will call those classes and methods using JAVA Reflection API but before that I want to load my Jar into class path at run time. I have a J Button and on click of that I am getting Jar Name and Jar path. But I am failing to load Jar to classpath at run time. Got some links but were not helpful. Please provide me with simple example. I should load my jar to classpath. That's the only problem for me.I will take care of that. Please help.

Answer 1

You can load classes at run time through the use of a ClassLoader , take a look at URLClassLoader for example

File yourJarFile = ...;
URLClassLoader classLoader = new URLClassLoader(new URL[]{yourJarFile.toURI().toURL()});

This will then allow you to load classes and instantiate them...

Class class = classLoader.loadClass("fully.qualified.packagename.to.your.AwesomeClass");

You can then instantiate them using something like...

Object obj = class.newInstance();

Or reflection if you want to use a specific constructor. Just remember, you won't be able to reference these classes directly within the current class loader context, as the current class loader knows nothing about them