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