java url jar包_Java绝对路径读取jar包 | 学步园

方法一：

package com.demo.action;

import java.lang.reflect.Method;

import java.net.URL;

import java.net.URLClassLoader;

public class Test {

public static void main(String[] args) {

// TODO Auto-generated method stub

try {

URL url = new URL("file:/D:/maven_web.jar");

@SuppressWarnings("resource")

URLClassLoader myClassLoader = new URLClassLoader( new URL[] { url } );

Class> myClass = myClassLoader.loadClass("com.huahua.inter.impl.UserImpl");

Method[] methods = myClass.getDeclaredMethods();

for (Method method : methods) {

System.out.println(method.getName());

}

} catch (Exception e) {

// TODO: handle exception

e.printStackTrace();

}

}

}

方法二：

package com.demo.action;

import java.io.File;

import java.lang.annotation.Annotation;

import java.lang.reflect.Method;

import java.net.URL;

import java.net.URLClassLoader;

import java.util.Enumeration;

import java.util.HashMap;

import java.util.LinkedHashSet;

import java.util.Map;

import java.util.Set;

import java.util.jar.JarEntry;

import java.util.jar.JarFile;

public class test1 {

public static void main(String[] args) {

String path = "D:\\maven_web.jar";//外部jar包的路径

Set> classes = new LinkedHashSet>();//所有的Class对象

Map, Annotation[]> classAnnotationMap = new HashMap, Annotation[]>();//每个Class对象上的注释对象

Map, Map> classMethodAnnoMap = new HashMap, Map >();//每个Class对象中每个方法上的注释对象

try {

@SuppressWarnings("resource")

JarFile jarFile = new JarFile(new File(path));

URL url = new URL("file:" + path);

@SuppressWarnings("resource")

ClassLoader loader = new URLClassLoader(new URL[]{url});//自己定义的classLoader类，把外部路径也加到load路径里，使系统去该路经load对象

Enumeration es = jarFile.entries();

while (es.hasMoreElements()) {

JarEntry jarEntry = (JarEntry) es.nextElement();

String name = jarEntry.getName();

//System.out.println(name);

if(name != null && name.endsWith(".class")){//只解析了.class文件，没有解析里面的jar包

//默认去系统已经定义的路径查找对象，针对外部jar包不能用

//Class> c = Thread.currentThread().getContextClassLoader().loadClass(name.replace("/", ".").substring(0,name.length() - 6));

Class> c = loader.loadClass(name.replace("/", ".").substring(0,name.length() - 6));//自己定义的loader路径可以找到

if(c.isInterface()) continue; //排除接口类

System.out.println(c);

classes.add(c);

Annotation[] classAnnos = c.getDeclaredAnnotations();

classAnnotationMap.put(c, classAnnos);

Method[] classMethods = c.getDeclaredMethods();

for (Method method : classMethods) {

System.out.println(method.getName());//打印所有自定义的方法

}

Map methodAnnoMap = new HashMap();

for(int i = 0;i

Annotation[] a = classMethods[i].getDeclaredAnnotations();

methodAnnoMap.put(classMethods[i], a);

}

classMethodAnnoMap.put(c, methodAnnoMap);

}

}

System.out.println(classes.size());

} catch (Exception e) {

e.printStackTrace();

}

}

}