java - 使用 Java 反射从类路径外加载类

Question

我想从不在类路径中的类加载类。有什么方法可以通过文件路径加载类而不是在类路径中？例如

ClassLoader.load("c:\MyClass.class");

Answer 1

示例取自 here :

// Create a File object on the root of the directory containing the class file  
File file = new File("c:\\myclasses\\");

try {
    // Convert File to a URL
    URL url = file.toURL();          // file:/c:/myclasses/
    URL[] urls = new URL[]{url};

    // Create a new class loader with the directory
    ClassLoader cl = new URLClassLoader(urls);

    // Load in the class; MyClass.class should be located in
    // the directory file:/c:/myclasses/com/mycompany
    Class cls = cl.loadClass("com.mycompany.MyClass");
} catch (MalformedURLException e) {
} catch (ClassNotFoundException e) {
}