【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
1 package org.nonbankcard.persist; 2 /** 3 * 该类会在nonbankcard-configure-0.0.1-SNAPSHOT.jar类中被引用 4 * @author sxf 5 * 6 */ 7 public class SxfApp { 8 private String name; 9 private String age; 10 private String dos; 11 public String getName() { 12 return name; 13 } 14 public void setName(String name) { 15 this.name = name; 16 } 17 public String getAge() { 18 return age; 19 } 20 public void setAge(String age) { 21 this.age = age; 22 } 23 public String getDos() { 24 return dos; 25 } 26 public void setDos(String dos) { 27 this.dos = dos; 28 } 29 30 }
2:nonbankcard-configure-0.0.1-SNAPSHOT.jar 中的代码
1 package com.nonbank.sxf.test.cls; 2 3 import java.util.ArrayList; 4 import java.util.List; 5 6 import org.nonbankcard.persist.SxfApp; 7 8 import com.alibaba.fastjson.JSON; 9 /** 10 * 该类中的代码引用了 11 * =>nonbankcard-persist-0.0.1-SNAPSHOT.jar中的代码 12 * =>fastjson-1.2.8.sec01.jar中的代码 13 * =>本jar包中的User类 14 * @author sxf 15 * 16 */ 17 public class SxfTestUtils { 18 19 /** 20 * 静态方法 21 * @param list 22 * @return 23 */ 24 public static String formatList(List<String> list){ 25 List<User> userList=new ArrayList<User>(); 26 List<SxfApp> apps=new ArrayList<SxfApp>(); 27 for(String str:list){ 28 User u=JSON.parseObject(str, User.class); 29 userList.add(u); 30 } 31 for(User usr:userList){ 32 System.out.println("SxfTestUtils.formatList()"+usr.getName()); 33 System.out.println("SxfTestUtils.formatList()"+usr.getAge()); 34 System.out.println("SxfTestUtils.formatList()"+usr.getDos()); 35 SxfApp sxfApp=new SxfApp(); 36 sxfApp.setName(usr.getName()); 37 sxfApp.setAge(usr.getAge()); 38 sxfApp.setDos(usr.getDos()); 39 apps.add(sxfApp); 40 } 41 42 StringBuilder builder=new StringBuilder(); 43 for(SxfApp app:apps){ 44 builder.append("@").append("姓名==>[").append(app.getName()).append("]年龄==>[").append(app.getAge()).append("]"); 45 builder.append("喜欢做的事情==>[").append(app.getDos()).append("]"); 46 } 47 return builder.toString().substring(1); 48 } 49 50 /** 51 * 非静态方法 52 * @param list 53 * @return 54 */ 55 public String formatEx(List<String> list){ 56 List<User> userList=new ArrayList<User>(); 57 List<SxfApp> apps=new ArrayList<SxfApp>(); 58 for(String str:list){ 59 User u=JSON.parseObject(str, User.class); 60 userList.add(u); 61 } 62 for(User usr:userList){ 63 System.out.println("SxfTestUtils.formatList()"+usr.getName()); 64 System.out.println("SxfTestUtils.formatList()"+usr.getAge()); 65 System.out.println("SxfTestUtils.formatList()"+usr.getDos()); 66 SxfApp sxfApp=new SxfApp(); 67 sxfApp.setName(usr.getName()); 68 sxfApp.setAge(usr.getAge()); 69 sxfApp.setDos(usr.getDos()); 70 apps.add(sxfApp); 71 } 72 73 StringBuilder builder=new StringBuilder(); 74 for(SxfApp app:apps){ 75 builder.append("@").append("姓名==>[").append(app.getName()).append("]年龄==>[").append(app.getAge()).append("]"); 76 builder.append("喜欢做的事情==>[").append(app.getDos()).append("]"); 77 } 78 return builder.toString().substring(1); 79 } 80 81 /** 82 * 非静态方法 83 * @param str 84 * @return 85 */ 86 public String sxf(String str){ 87 System.out.println("SxfTestUtils.sxf(aaaaaaaaaaaaaaaaaaaaaaaaaaaa)"); 88 return "记载======>"+str; 89 } 90 }
3:测试类
1 package org.nonbankcard.commons; 2 3 import java.io.File; 4 import java.io.FileFilter; 5 import java.lang.reflect.Constructor; 6 import java.lang.reflect.InvocationTargetException; 7 import java.lang.reflect.Method; 8 import java.net.MalformedURLException; 9 import java.net.URL; 10 import java.net.URLClassLoader; 11 import java.util.ArrayList; 12 import java.util.List; 13 14 import org.mvel2.util.ThisLiteral; 15 /** 16 * 17 * @author sxf 18 * 19 */ 20 public class SxfTestClass { 21 22 private final String CLASS_NAME="com.nonbank.sxf.test.cls.SxfTestUtils"; 23 //工具类对应的对象 24 private Object object=null; 25 //格式化的方法对象，静态。List作为形参 26 private Method formatListMethod=null; 27 //非静态的方法对象。List作为形参 28 private Method formatExMethod=null; 29 //非静态的方法对象。String作为形参 30 private Method sxfMehod=null; 31 32 33 34 35 /** 36 * 构造函数中，加载指定路径的jar包。调用jar包中的方法 37 * @throws MalformedURLException 38 * @throws ClassNotFoundException 39 * @throws NoSuchMethodException 40 * @throws SecurityException 41 * @throws InstantiationException 42 * @throws IllegalAccessException 43 * @throws IllegalArgumentException 44 * @throws InvocationTargetException 45 */ 46 public SxfTestClass() throws MalformedURLException, ClassNotFoundException, NoSuchMethodException, SecurityException, InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException{ 47 //jar包所在目录 48 File file=new File("/usr/sxf/testcls"); 49 50 //加载目录下所有的jar文件 51 File[] files=file.listFiles(new FileFilter() { 52 public boolean accept(File pathname) { 53 String name = pathname.getName().toLowerCase(); 54 System.out.println("SxfTestClass.enclosing_method()"+name); 55 return name.endsWith("jar"); 56 } 57 }); 58 //classLoarder加载 59 URL[] urls = new URL[files.length]; 60 for(int i = 0; i < files.length; i++) { 61 urls[i] = new URL("file",null,files[i].getAbsolutePath()); 62 } 63 //将jar包全部加载到classLoader中 64 ClassLoader classLoader = new URLClassLoader(urls, null); 65 66 //反射生成jar包中的类的对象，和要执行方法的对象 67 Class cls=classLoader.loadClass(CLASS_NAME); 68 //构造函数 69 Constructor constructor = cls.getConstructor(new Class[]{}); 70 //反射生成对象 71 this.object=constructor.newInstance(new Object[]{}); 72 //反射生成要执行方法的对象 73 this.formatListMethod=cls.getDeclaredMethod("formatList",new Class[] {List.class}); 74 this.formatExMethod=cls.getDeclaredMethod("formatEx", new Class[] {List.class}); 75 this.sxfMehod=cls.getDeclaredMethod("sxf", new Class[] {String.class}); 76 77 } 78 79 public static void main(String[] args) throws MalformedURLException, ClassNotFoundException, NoSuchMethodException, SecurityException, InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException { 80 SxfTestClass sxfTestClass=new SxfTestClass(); 81 sxfTestClass.testclassLoader(); 82 } 83 84 /** 85 * 静态，非静态的方法都可被执行 86 * @throws IllegalAccessException 87 * @throws IllegalArgumentException 88 * @throws InvocationTargetException 89 * 90 */ 91 public void testclassLoader() throws IllegalAccessException, IllegalArgumentException, InvocationTargetException{ 92 String a="{'name':'ddd','age':'28','dos':'学些写java代码'}"; 93 String b="{'name':'eee','age':'28','dos':'打篮球'}"; 94 List<String> list=new ArrayList<String>(); 95 list.add(a); 96 list.add(b); 97 Object strObject=formatListMethod.invoke(object, list); 98 System.out.println("SxfTestClass.testclassLoader()"+strObject); 99 100 System.out.println("================================"); 101 102 Object strObject2=formatExMethod.invoke(this.object, list); 103 System.out.println("SxfTestClass.testclassLoader()"+strObject2); 104 105 System.out.println("================================"); 106 107 Object object=sxfMehod.invoke(this.object, "东"); 108 System.out.println("SxfTestClass.testclassLoader()"+object); 109 110 } 111 112 113 /** 114 * 115 测试结果： 116 SxfTestClass.enclosing_method()nonbankcard-configure-0.0.1-snapshot.jar 117 SxfTestClass.enclosing_method()nonbankcard-persist-0.0.1-snapshot.jar 118 SxfTestClass.enclosing_method()fastjson-1.2.8.sec01.jar 119 SxfTestUtils.formatList()ddd 120 SxfTestUtils.formatList()28 121 SxfTestUtils.formatList()学些写java代码 122 SxfTestUtils.formatList()eee 123 SxfTestUtils.formatList()28 124 SxfTestUtils.formatList()打篮球 125 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] 126 ================================ 127 SxfTestUtils.formatList()ddd 128 SxfTestUtils.formatList()28 129 SxfTestUtils.formatList()学些写java代码 130 SxfTestUtils.formatList()eee 131 SxfTestUtils.formatList()28 132 SxfTestUtils.formatList()打篮球 133 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] 134 ================================ 135 SxfTestUtils.sxf(aaaaaaaaaaaaaaaaaaaaaaaaaaaa) 136 SxfTestClass.testclassLoader()记载======>东 137 138 */ 139 140 141 }
【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
