URLClassLoader 获取外部的jar文件以及class文件

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URLClassLoader 获取外部的jar文件以及class文件

package spring.agent;

import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLClassLoader;

import org.junit.Test;

public class URLClassLoaderTest {

    private String pathJar = "D:/MyWorkSpacePractice/ACL/wcl-persist/target/wcl-persist-3.3.23-SNAPSHOT.jar";
   
    // class文件路径的path，不应该包括类报名路径
    private String pathClass = "D:/MyWorkSpacePractice/ACL/wcl-web/target/wcl-web-3.3.23-SNAPSHOT/WEB-INF/classes/";

    /**
     * 加载jar包下的interface接口
     */
    @Test
    public void testUrlJarClassLoader() throws MalformedURLException, ClassNotFoundException, NoSuchFieldException,
            SecurityException, IllegalArgumentException, IllegalAccessException {
        URL url = new URL("file:" + pathJar);
        URLClassLoader urlClassLoader = new URLClassLoader(new URL[] { url }); // 加载外部的jar包
        Class<?> clazz = urlClassLoader.loadClass("cn.homecredit.wcl.persist.primary.dao.CheckJournalDao");
        Field field = clazz.getDeclaredField("FIND_CHECK_SEQUENCE"); // 接口
        System.out.println(field.getName() + ":" + field.get(clazz)); // 接口
    }

    /**
     * 加载外部的class文件
     *
     */
    @Test
    public void testClassFileClassLoader() throws MalformedURLException, ClassNotFoundException, NoSuchFieldException,
            SecurityException, IllegalArgumentException, IllegalAccessException, InstantiationException,
            NoSuchMethodException, InvocationTargetException {
        URL url = new URL("file:" + pathClass);
        @SuppressWarnings("resource")
        URLClassLoader urlClassLoader = new URLClassLoader(new URL[] { url }); // 加载外部的jar包
        Class<?> clazz = urlClassLoader.loadClass("cn.homecredit.wcl.web.model.PosSelectionForm");
        Object obj = clazz.newInstance();
        Method method = clazz.getMethod("toString");
        Object o = method.invoke(obj);
        System.out.println(o);
    }
}