package onlyfun.caterpillar;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLClassLoader;
public class ClassLoaderDemo {
public static void main(String[] args) {
try {
// 測試路徑
String classPath = args[0];
// 測試類別
String className = args[1];
URL url1 = new URL(classPath);
// 建立ClassLoader
ClassLoader loader1 =
new URLClassLoader(new URL[] {url1});
// 載入指定類別
Class c1 = loader1.loadClass(className);
// 顯示類別描述
System.out.println(c1);
URL url2 = new URL(classPath);
ClassLoader loader2 =
new URLClassLoader(new URL[] {url2});
Class c2 = loader2.loadClass(className);
System.out.println(c2);
System.out.println("c1 與 c1 為同一實例?"
+ (c1 == c2));
}
catch(ArrayIndexOutOfBoundsException e) {
System.out.println("沒有指定類別載入路徑與名稱");
}
catch(MalformedURLException e) {
System.out.println("載入路徑錯誤");
}
catch(ClassNotFoundException e) {
System.out.println("找不到指定的類別");
}
}
}