手動部署jar包,太low!動態(tài)上傳熱部署真爽!
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2024-04-19 13:00
本文來源:https://blog.csdn.net/zhangzhiqiang_0912
近期開發(fā)系統(tǒng)過程中遇到的一個需求,系統(tǒng)給定一個接口,用戶可以自定義開發(fā)該接口的實現(xiàn),并將實現(xiàn)打成jar包,上傳到系統(tǒng)中。系統(tǒng)完成熱部署,并切換該接口的實現(xiàn)。
定義簡單的接口
public interface Calculator {
int calculate(int a, int b);
int add(int a, int b);
}
該接口的一個簡單的實現(xiàn)
calculate方法對應注解方式,add方法對應反射方式。計算器接口實現(xiàn)類的代碼如下:
@Service
public class CalculatorImpl implements Calculator {
@Autowired
CalculatorCore calculatorCore;
/**
* 注解方式
*/
@Override
public int calculate(int a, int b) {
int c = calculatorCore.add(a, b);
return c;
}
/**
* 反射方式
*/
@Override
public int add(int a, int b) {
return new CalculatorCore().add(a, b);
}
}
CalculatorCore的目的是為了驗證在注解模式下,系統(tǒng)可以完整的構造出bean的依賴體系,并注冊到當前spring容器中。CalculatorCore的代碼如下:
@Service
public class CalculatorCore {
public int add(int a, int b) {
return a+b;
}
}
反射方式熱部署
private static String jarAddress = "E:/zzq/IDEA_WS/CalculatorTest/lib/Calculator.jar";
private static String jarPath = "file:/" + jarAddress;
/**
* 熱加載Calculator接口的實現(xiàn) 反射方式
*/
public static void hotDeployWithReflect() throws Exception {
URLClassLoader urlClassLoader = new URLClassLoader(new URL[]{new URL(jarPath)}, Thread.currentThread().getContextClassLoader());
Class clazz = urlClassLoader.loadClass("com.nci.cetc15.calculator.impl.CalculatorImpl");
Calculator calculator = (Calculator) clazz.newInstance();
int result = calculator.add(1, 2);
System.out.println(result);
}
注解方式熱部署
/**
* 加入jar包后 動態(tài)注冊bean到spring容器,包括bean的依賴
*/
public static void hotDeployWithSpring() throws Exception {
Set<String> classNameSet = DeployUtils.readJarFile(jarAddress);
URLClassLoader urlClassLoader = new URLClassLoader(new URL[]{new URL(jarPath)}, Thread.currentThread().getContextClassLoader());
for (String className : classNameSet) {
Class clazz = urlClassLoader.loadClass(className);
if (DeployUtils.isSpringBeanClass(clazz)) {
BeanDefinitionBuilder beanDefinitionBuilder = BeanDefinitionBuilder.genericBeanDefinition(clazz);
defaultListableBeanFactory.registerBeanDefinition(DeployUtils.transformName(className), beanDefinitionBuilder.getBeanDefinition());
}
}
}
/**
* 讀取jar包中所有類文件
*/
public static Set<String> readJarFile(String jarAddress) throws IOException {
Set<String> classNameSet = new HashSet<>();
JarFile jarFile = new JarFile(jarAddress);
Enumeration<JarEntry> entries = jarFile.entries();//遍歷整個jar文件
while (entries.hasMoreElements()) {
JarEntry jarEntry = entries.nextElement();
String name = jarEntry.getName();
if (name.endsWith(".class")) {
String className = name.replace(".class", "").replaceAll("/", ".");
classNameSet.add(className);
}
}
return classNameSet;
}
/**
* 方法描述 判斷class對象是否帶有spring的注解
*/
public static boolean isSpringBeanClass(Class<?> cla) {
if (cla == null) {
return false;
}
//是否是接口
if (cla.isInterface()) {
return false;
}
//是否是抽象類
if (Modifier.isAbstract(cla.getModifiers())) {
return false;
}
if (cla.getAnnotation(Component.class) != null) {
return true;
}
if (cla.getAnnotation(Repository.class) != null) {
return true;
}
if (cla.getAnnotation(Service.class) != null) {
return true;
}
return false;
}
/**
* 類名首字母小寫 作為spring容器beanMap的key
*/
public static String transformName(String className) {
String tmpstr = className.substring(className.lastIndexOf(".") + 1);
return tmpstr.substring(0, 1).toLowerCase() + tmpstr.substring(1);
}
刪除jar時,需要同時刪除spring容器中注冊的bean
/**
* 刪除jar包時 需要在spring容器刪除注入
*/
public static void delete() throws Exception {
Set<String> classNameSet = DeployUtils.readJarFile(jarAddress);
URLClassLoader urlClassLoader = new URLClassLoader(new URL[]{new URL(jarPath)}, Thread.currentThread().getContextClassLoader());
for (String className : classNameSet) {
Class clazz = urlClassLoader.loadClass(className);
if (DeployUtils.isSpringBeanClass(clazz)) {
defaultListableBeanFactory.removeBeanDefinition(DeployUtils.transformName(className));
}
}
}
測試
ApplicationContext applicationContext = new ClassPathXmlApplicationContext("applicationContext.xml");
DefaultListableBeanFactory defaultListableBeanFactory = (DefaultListableBeanFactory) applicationContext.getAutowireCapableBeanFactory();
while (true) {
try {
hotDeployWithReflect();
// hotDeployWithSpring();
// delete();
} catch (Exception e) {
e.printStackTrace();
Thread.sleep(1000 * 10);
}
}
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