# 동적 Jar loading 프로그램 #### 동적 jar 로딩 및 동적 method 호출 - ``` 1 package com.exec; 2 3 import java.io.File; 4 import java.io.FileFilter; 5 import java.io.FilenameFilter; 6 import java.lang.reflect.InvocationTargetException; 7 import java.lang.reflect.Method; 8 import java.net.URL; 9 import java.net.URLClassLoader; 10 import java.util.Arrays; 11 12 public class ExecTest { 13 14 public static void main(String[] args) throws NoSuchMethodException, SecurityException, ClassNotFoundException, InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException { 15 16 // 코리안리 EAI customer function 위치 (고정 값) 17 String dir = "C:\\eclipse-workspace\\com.exec\\src\\main\\resources\\deployFilder"; 18 // 코리안리 EAI customer function prefix (고정 값) 19 String jarName = "kr.co.koreanre.eai"; 20 // 코리안리 EAI customer function Class 명 분류 할 수도 있다. 21 String className = "kr.co.koreanre.eai.execEaiFunctionClass"; 22 // 코리안리 EAI customer function method 명은 고정 예정 23 String methodName = "execMathod"; 24 // 코리안리 EAI customer function method에 전달되는 문자열 전달 25 String param = "Call method ,"; 26 27 ExecTest ex = new ExecTest(); 28 29 30 // kr.co.koreanre.eai-202110280920.jar의 include 여부를 확인, include되어도 최신 버전이 아닌 경우는 false로 return 31 if(!ex.checkLoadedJarList(dir,jarName)) 32 { 33 System.out.println(" > Do not include : " + jarName ); 34 // 최신 버전으로 include 35 ex.loadJar(dir); 36 } 37 38 String returnString = ex.execMethod(className, methodName, param); 39 System.out.println(" > Return Value : " + returnString); 40 ex.checkLoadedJarList(dir, jarName); 41 } 42 43 44 45 46 /* =================================================================================== */ 47 48 49 50 51 52 /** 53 * kr.co.koreanre.eai-202110280920.jar의 로드 여부를 확인 54 * 55 * @param jarName 56 * @return boolean 57 */ 58 private boolean checkLoadedJarList(String dir, String jarName) { 59 System.out.println("\n>> Start Check loaded Jar list " ); 60 boolean includJar = false; 61 62 ClassLoader classLoader = ClassLoader.getSystemClassLoader(); 63 URL[] urls = ((URLClassLoader)classLoader).getURLs(); 64 65 for(URL url: urls){ 66 if( url.getFile().toLowerCase().contains(".jar") ) { 67 System.out.println(" > Included Jar : " + url.getFile()); 68 if(url.getFile().toLowerCase().contains(jarName)) 69 { 70 if(isLoadNewVersionJar(dir, url.getFile())) 71 { 72 includJar = true; 73 }else { 74 includJar = false; 75 } 76 }else { 77 includJar = false; 78 } 79 } 80 } 81 return includJar; 82 } 83 84 /** 85 * 디렉토리 안에서 파라메터로 전달한 jar 파일이 최신인지 여부를 판단 86 * @param dir 검토 폴더 87 * @param jarName 비교 jar 88 * @return boolean 89 */ 90 private boolean isLoadNewVersionJar(String dir, String jarName) { 91 boolean isNweVersion = false; 92 93 File file = new File(dir); 94 File[] fileNameList = file.listFiles(new FilenameFilter() { 95 public boolean accept(File dir, String name) { 96 return name.endsWith("jar"); 97 } 98 }); 99 100 if(fileNameList.length==0) { 101 throw new NoClassDefFoundError("Koreanre EAI jar not exist ! "); 102 }else { 103 Arrays.sort(fileNameList); 104 String oldVersion = jarName.replace("\\", "/").substring(jarName.replace("\\", "/").lastIndexOf('/') + 1); 105 String newVersion = fileNameList[fileNameList.length-1].getPath().replace("\\", "/"); 106 System.out.println(" > OLD : " + oldVersion ); 107 System.out.println(" > NEW : " + newVersion.substring(newVersion.lastIndexOf('/') + 1)); 108 if(oldVersion.equals(newVersion.substring(newVersion.lastIndexOf('/') + 1))) 109 { 110 System.out.println(" > is New Version"); 111 isNweVersion = true; 112 }else { 113 System.out.println(" > is Not New Version"); 114 isNweVersion = false; 115 } 116 } 117 118 return isNweVersion; 119 } 120 121 /** 122 * Method를 실행 123 * @param className 124 * @param methodName 125 * @param param 126 * @return 127 * @throws ClassNotFoundException 128 * @throws NoSuchMethodException 129 * @throws SecurityException 130 * @throws InstantiationException 131 * @throws IllegalAccessException 132 * @throws IllegalArgumentException 133 * @throws InvocationTargetException 134 */ 135 private String execMethod(String className, String methodName, String param) throws ClassNotFoundException, NoSuchMethodException, SecurityException, InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException { 136 System.out.println("\n>> Start exec method ! " ); 137 138 ClassLoader cl = Thread.currentThread().getContextClassLoader(); 139 Class clazz = cl.loadClass(className); 140 141 Method m = clazz.getMethod(methodName, param.getClass() ); 142 m.setAccessible(true); 143 144 System.out.println(" > Classd Name : " + className); 145 System.out.println(" > Method Name : " + methodName); 146 System.out.println(" > Params Value : " + param); 147 System.out.println(" > Return Type : " + m.getReturnType()); 148 149 if (m.getReturnType() != String.class) { 150 System.out.println(" > Return type Stirng only : " + m.getReturnType() ); 151 throw new NoSuchMethodException(methodName); 152 } 153 154 if (m.getModifiers() == 9) { 155 System.out.println(" > Not allowed Static method : " + m.getModifiers() ); 156 throw new NoSuchMethodException(methodName); 157 } 158 159 if (m.getModifiers() != 1) { 160 System.out.println(" > Public method only : " + m.getModifiers() ); 161 throw new NoSuchMethodException(methodName); 162 } 163 164 Object bbb = clazz.newInstance(); 165 String returnMsg = ""; 166 returnMsg = (String)m.invoke(bbb , new Object[] { param }); 167 168 return returnMsg; 169 170 } 171 172 173 /** 174 * 해당 디렉토리의 최신 버전의 jar를 적용한다. 175 * @param dir 176 * @throws NoSuchMethodException 177 * @throws SecurityException 178 */ 179 private void loadJar(final String dir) throws NoSuchMethodException, SecurityException { 180 System.out.println("\n>> LoadJar "); 181 final URLClassLoader loader = (URLClassLoader)Thread.currentThread().getContextClassLoader(); 182 final Method method = URLClassLoader.class.getDeclaredMethod("addURL", new Class[]{URL.class}); 183 method.setAccessible(true); 184 185 new File(dir).listFiles(new FileFilter() { 186 public boolean accept(File jar) { 187 if( jar.toString().toLowerCase().contains(".jar") ){ 188 try{ 189 if(isLoadNewVersionJar(dir, jar.toString())) { 190 method.invoke(loader, new Object[]{jar.toURI().toURL()}); 191 System.out.println(" > " + jar.toURI() + " is loaded."); 192 } 193 194 }catch(Exception e){ 195 System.out.println(jar.toURI() + " can't load."); 196 } 197 } 198 return false; 199 } 200 }); 201 } 202 203 } ``` - 호출을 받는 소스

[줄 번호 보이기/숨기기](http://web.joang.com:9000/jcook/DynamicJarLoading)

``` 1 package kr.co.koreanre.eai; 2 3 public class execEaiFunctionClass { 4 5 public execEaiFunctionClass() { 6 System.out.println(" > Init #1" ); 7 } 8 9 public String execMathod( String obj ) { 10 11 String reString = new String(); 12 13 return reString + "= called test1"; 14 15 } 16 17 } ``` - 호출을 받는 곳 pom.xml

``` 1 2 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 3 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> 4 4.0.0 5 kr.co.koreanre.eai 6 kr.co.koreanre.eai 7 202110280920 8 Test1 9 10 11 12 13 14 org.apache.maven.plugins 15 maven-resources-plugin 16 2.3 17 18 19 maven-resources-plugin 20 3.0.2 21 22 23 copy-resource-one 24 install 25 26 copy-resources 27 28 29 ${basedir}/../com.exec/src/main/resources/deployFilder 30 31 32 ${basedir}/target 33 34 *.jar 35 36 37 38 39 40 41 42 43 44 45 46 ```