classloader

The following code adds jar file to the build path, it works fine with Java 8. However, it throws exception with Java 9, the exception is related to the cast to URLClassLoader. Any ideas how this can be solved? an optimal solution will edit it to work with both Java 8 & 9. private static int AddtoBuildPath(File f) { try { URI u = f.toURI(); URLClassLoader urlClassLoader = (URLClassLoader) ClassLoader.getSystemClassLoader(); Class<URLClassLoader> urlClass = URLClassLoader.class; Method method = urlClass.getDeclaredMethod("addURL", URL.class); method.setAccessible(true); method.invoke

I'm a newbie to Java and just starting to figure out the concept of class loaders. Right now I am having some issues with log4j regarding its use of the thread context classloader. I'm getting the following errors: A "org.apache.log4j.ConsoleAppender" object is not assignable to a "org.apache.log4j.Appender" variable. The class "org.apache.log4j.Appender" was loaded by [java.net.URLClassLoader@105691e] whereas object of type "org.apache.log4j.ConsoleAppender" was loaded by [sun.misc.Launcher$AppClassLoader@16930e2]. Could not instantiate appender named "CONSOLE". My application works roughly

WebSphere comes with parent last and parent first. Is this Java EE compliant? Is this supported by all application servers that are Java EE 5 compliant? Aravind R. Yarram I did my own research (going through the specs and few blogs) and below is what I've figured EAR The spec DOES NOT define or mandate how the class loaders should work within an EAR. It however defines that there SHOULD be per thread context class loader for runtime loading of classes there MIGHT be a hierarchical class loading mechanism for resolving classes (app server vendors are free to implement whichever way they choose

Hiii... I want to get the content of properties file into InputStream class object using getSystemResourceAsStream(). I have built the sample code. It works well using main() method,but when i deploy the project and run on the server, properties file path cannot obtained ... so inputstream object store null value. Sample code is here.. public class ReadPropertyFromFile { public static Logger logger = Logger.getLogger(ReadPropertyFromFile.class); public static String readProperty(String fileName, String propertyName) { String value = null; try { //fileName = "api.properties"; //propertyName =

I'm trying to practice myself with custom class loaders, and I've some questions. Is there a way to indicate the JVM to use my custom class loader globally? For example, I wrote small app running under Tomcat 6. The servlet is managed by the container, where should I set my class loader? In addition, the webapp uses some 3rd party jars, can I control the classes loading of those jars? Are the answers to the above will be different in case of standalone app? Thanks! You can set the system default class loader as a JVM argument: java -Djava.system.class.loader =com.test.YourCustomClassLoader com