Spring源码学习之：ClassLoader学习（5）-自测

【一】测试目的（ClassLoader的作用）

1：测试涉及三个jar包，nonbankcard-configure-0.0.1-SNAPSHOT.jar，nonbankcard-persist-0.0.1-SNAPSHOT.jar，fastjson-1.2.8.sec01.jar

2：将这三个jar包放在指定的目录里（/usr/sxf/testcls）

3：在项目中编辑类加载的jar，加载到内存中，执行jar包中的方法

【二】测试代码

1：nonbankcard-persist-0.0.1-SNAPSHOT.jar中的代码

 package org.nonbankcard.persist;
 /**
  * 该类会在nonbankcard-configure-0.0.1-SNAPSHOT.jar类中被引用
  * @author sxf
  *
  */
 public class SxfApp {
     private String name;
     private String age;
     private String dos;
     public String getName() {
         return name;
     }
     public void setName(String name) {
         this.name = name;
     }
     public String getAge() {
         return age;
     }
     public void setAge(String age) {
         this.age = age;
     }
     public String getDos() {
         return dos;
     }
     public void setDos(String dos) {
         this.dos = dos;
     }

 }

2:nonbankcard-configure-0.0.1-SNAPSHOT.jar 中的代码

 package com.nonbank.sxf.test.cls;

 import java.util.ArrayList;
 import java.util.List;

 import org.nonbankcard.persist.SxfApp;

 import com.alibaba.fastjson.JSON;
 /**
  * 该类中的代码引用了
  * =>nonbankcard-persist-0.0.1-SNAPSHOT.jar中的代码
  * =>fastjson-1.2.8.sec01.jar中的代码
  * =>本jar包中的User类
  * @author sxf
  *
  */
 public class SxfTestUtils {

     /**
      * 静态方法
      * @param list
      * @return
      */
     public static String formatList(List<String> list){
         List<User> userList=new ArrayList<User>();
         List<SxfApp> apps=new ArrayList<SxfApp>();
         for(String str:list){
             User u=JSON.parseObject(str, User.class);
             userList.add(u);
         }
         for(User usr:userList){
             System.out.println("SxfTestUtils.formatList()"+usr.getName());
             System.out.println("SxfTestUtils.formatList()"+usr.getAge());
             System.out.println("SxfTestUtils.formatList()"+usr.getDos());
             SxfApp sxfApp=new SxfApp();
             sxfApp.setName(usr.getName());
             sxfApp.setAge(usr.getAge());
             sxfApp.setDos(usr.getDos());
             apps.add(sxfApp);
         }

         StringBuilder builder=new StringBuilder();
         for(SxfApp app:apps){
             builder.append("@").append("姓名==>[").append(app.getName()).append("]年龄==>[").append(app.getAge()).append("]");
             builder.append("喜欢做的事情==>[").append(app.getDos()).append("]");
         }
         return builder.toString().substring(1);
     }

     /**
      * 非静态方法
      * @param list
      * @return
      */
     public String formatEx(List<String> list){
         List<User> userList=new ArrayList<User>();
         List<SxfApp> apps=new ArrayList<SxfApp>();
         for(String str:list){
             User u=JSON.parseObject(str, User.class);
             userList.add(u);
         }
         for(User usr:userList){
             System.out.println("SxfTestUtils.formatList()"+usr.getName());
             System.out.println("SxfTestUtils.formatList()"+usr.getAge());
             System.out.println("SxfTestUtils.formatList()"+usr.getDos());
             SxfApp sxfApp=new SxfApp();
             sxfApp.setName(usr.getName());
             sxfApp.setAge(usr.getAge());
             sxfApp.setDos(usr.getDos());
             apps.add(sxfApp);
         }

         StringBuilder builder=new StringBuilder();
         for(SxfApp app:apps){
             builder.append("@").append("姓名==>[").append(app.getName()).append("]年龄==>[").append(app.getAge()).append("]");
             builder.append("喜欢做的事情==>[").append(app.getDos()).append("]");
         }
         return builder.toString().substring(1);
     }

     /**
      * 非静态方法
      * @param str
      * @return
      */
     public String sxf(String str){
         System.out.println("SxfTestUtils.sxf(aaaaaaaaaaaaaaaaaaaaaaaaaaaa)");
         return "记载======>"+str;
     }
 }

3:测试类

 package org.nonbankcard.commons;

 import java.io.File;
 import java.io.FileFilter;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.net.MalformedURLException;
 import java.net.URL;
 import java.net.URLClassLoader;
 import java.util.ArrayList;
 import java.util.List;

 import org.mvel2.util.ThisLiteral;
 /**
  *
  * @author sxf
  *
  */
 public class SxfTestClass {

     private final String CLASS_NAME="com.nonbank.sxf.test.cls.SxfTestUtils";
     //工具类对应的对象
     private Object object=null;
     //格式化的方法对象，静态。List作为形参
     private Method formatListMethod=null;
     //非静态的方法对象。List作为形参
     private Method formatExMethod=null;
     //非静态的方法对象。String作为形参
     private Method sxfMehod=null;

     /**
      * 构造函数中，加载指定路径的jar包。调用jar包中的方法
      * @throws MalformedURLException
      * @throws ClassNotFoundException
      * @throws NoSuchMethodException
      * @throws SecurityException
      * @throws InstantiationException
      * @throws IllegalAccessException
      * @throws IllegalArgumentException
      * @throws InvocationTargetException
      */
     public SxfTestClass() throws MalformedURLException, ClassNotFoundException, NoSuchMethodException, SecurityException, InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException{
         //jar包所在目录
         File file=new File("/usr/sxf/testcls");

         //加载目录下所有的jar文件
         File[] files=file.listFiles(new FileFilter() {
             public boolean accept(File pathname) {
                 String name = pathname.getName().toLowerCase();
                 System.out.println("SxfTestClass.enclosing_method()"+name);
                  return name.endsWith("jar");
             }
         });
         //classLoarder加载
         URL[] urls = new URL[files.length];
          for(int i = 0; i < files.length; i++) {
               urls[i] = new URL("file",null,files[i].getAbsolutePath());
          }
          //将jar包全部加载到classLoader中
          ClassLoader classLoader = new URLClassLoader(urls, null);

          //反射生成jar包中的类的对象，和要执行方法的对象
          Class cls=classLoader.loadClass(CLASS_NAME);
          //构造函数
          Constructor constructor    = cls.getConstructor(new Class[]{});
          //反射生成对象
          this.object=constructor.newInstance(new Object[]{});
          //反射生成要执行方法的对象
          this.formatListMethod=cls.getDeclaredMethod("formatList",new Class[] {List.class});
          this.formatExMethod=cls.getDeclaredMethod("formatEx", new Class[] {List.class});
          this.sxfMehod=cls.getDeclaredMethod("sxf",  new Class[] {String.class});

     }

     public static void main(String[] args) throws MalformedURLException, ClassNotFoundException, NoSuchMethodException, SecurityException, InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException {
         SxfTestClass sxfTestClass=new SxfTestClass();
         sxfTestClass.testclassLoader();
     }

     /**
      * 静态，非静态的方法都可被执行
      * @throws IllegalAccessException
      * @throws IllegalArgumentException
      * @throws InvocationTargetException
      *
      */
     public void testclassLoader() throws IllegalAccessException, IllegalArgumentException, InvocationTargetException{
         String a="{'name':'ddd','age':'28','dos':'学些写java代码'}";
         String b="{'name':'eee','age':'28','dos':'打篮球'}";
         List<String> list=new ArrayList<String>();
         list.add(a);
         list.add(b);
         Object strObject=formatListMethod.invoke(object, list);
         System.out.println("SxfTestClass.testclassLoader()"+strObject);

         System.out.println("================================");

         Object strObject2=formatExMethod.invoke(this.object, list);
         System.out.println("SxfTestClass.testclassLoader()"+strObject2);

         System.out.println("================================");

         Object object=sxfMehod.invoke(this.object, "东");
         System.out.println("SxfTestClass.testclassLoader()"+object);

     }

     /**
      *
 测试结果：
 SxfTestClass.enclosing_method()nonbankcard-configure-0.0.1-snapshot.jar
 SxfTestClass.enclosing_method()nonbankcard-persist-0.0.1-snapshot.jar
 SxfTestClass.enclosing_method()fastjson-1.2.8.sec01.jar
 SxfTestUtils.formatList()ddd
 SxfTestUtils.formatList()28
 SxfTestUtils.formatList()学些写java代码
 SxfTestUtils.formatList()eee
 SxfTestUtils.formatList()28
 SxfTestUtils.formatList()打篮球
 SxfTestClass.testclassLoader()姓名==>[ddd]年龄==>[28]喜欢做的事情==>[学些写java代码]@姓名==>[eee]年龄==>[28]喜欢做的事情==>[打篮球]
 ================================
 SxfTestUtils.formatList()ddd
 SxfTestUtils.formatList()28
 SxfTestUtils.formatList()学些写java代码
 SxfTestUtils.formatList()eee
 SxfTestUtils.formatList()28
 SxfTestUtils.formatList()打篮球
 SxfTestClass.testclassLoader()姓名==>[ddd]年龄==>[28]喜欢做的事情==>[学些写java代码]@姓名==>[eee]年龄==>[28]喜欢做的事情==>[打篮球]
 ================================
 SxfTestUtils.sxf(aaaaaaaaaaaaaaaaaaaaaaaaaaaa)
 SxfTestClass.testclassLoader()记载======>东

      */

 }

【三】测试结果

1:执行目录必须存在，要调用方法依赖的所有jar包，否则会抛出异常