我已经下载了 aspectJ.jar 文件并将其解压到临时目录中(此 jar 文件仅用于测试目的)。
我有以下代码:
public class TestUrlClassLoader {
public static void main(String [] args) throws MalformedURLException, ClassNotFoundException {
File file = new File("C:\\temp\\org\\aspectj\\lang\\JoinPoint.class");
URLClassLoader loader = URLClassLoader.newInstance(new URL[]{file.toURI().toURL()});
Class<?> aClass = loader.loadClass("org.aspectj.lang.JoinPoint");
System.out.println(aClass.toString());
}
}
包含 JoinPoint 类的文件存在，但我收到 ClassNotFoundException。有人可以帮助我吗？
最佳答案
根据URLClassLoader的javadoc，
[...] (URLClassLoader) is used to load classes and resources from a search path of URLs referring to both JAR files and directories. Any URL that ends with a '/' is assumed to refer to a directory. Otherwise, the URL is assumed to refer to a JAR file which will be opened as needed.
您应该删除 JoinPoint.class 的完整路径，并尝试使用要添加到类路径中的目录，例如
File file = new File("C:\\temp");
URLClassLoader loader = URLClassLoader.newInstance(new URL[]{file.toURI().toURL()});
引用javadoc: http://docs.oracle.com/javase/7/docs/api/java/net/URLClassLoader.html
关于java - 为什么URLClassLoader不加载类？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/18850403/