classloader getresource jar包资源冲突情况，父亲为大，兄弟之间，谁先加载谁牛逼（二）

getResources一起加载,URL.openStream

 

public class LcProperty {

    public static void main(String [] x) throws IOException {

    }

    public static String read(String conf) throws IOException {
        ..
    }

    public static String reads(String conf) throws IOException {
        System.out.println(LcProperty.class.getClassLoader().getResources(conf));
        Enumeration<URL> urlEnumeration = LcProperty.class.getClassLoader().getResources(conf);
        while(urlEnumeration.hasMoreElements()){
            URL url = urlEnumeration.nextElement();
            System.out.println(url);
            InputStream inputStream = url.openStream();
            byte [] bytes = new byte[20];
            inputStream.read(bytes);
            String out = new String(bytes);
            System.out.println(out);
        }
        return urlEnumeration.toString();

    }
}

 

/*
        故意让brother在前面，以此证明即使在sub.jar中调用getresource也不会优先查
        sub中的资源或类，而会去查被优先加载的brother.jar
        这个加载顺序取决于操作系统
        */

//        ////
        Method method3 = c1.getMethod("reads", String.class);
        System.out.println("start reads father.conf");
        method3.invoke(null, "father.conf");
        System.out.println("start reads self.conf");
        method3.invoke(null, "self.conf");
        System.out.println("start reads brother.conf");
        method3.invoke(null, "brother.conf");

        Method method4 = c2.getMethod("reads", String.class);
        System.out.println("start reads father.conf");
        method4.invoke(null, "father.conf");
        System.out.println("start reads self.conf");
        method4.invoke(null, "self.conf");
        System.out.println("start reads brother.conf");
        method4.invoke(null, "brother.conf");

 

start reads father.conf
sun.misc.CompoundEnumeration@34c45dca
file:/Users/joyce/work/MyTest/MyMain/target/classes/father.conf
father
jar:file:/Users/sunyuming/Documents/tool/jars//MySub-1.0.0-jar-with-dependencies.jar!/father.conf
self
jar:file:/Users/sunyuming/Documents/tool/jars//MySubBrother-1.0.0-jar-with-dependencies.jar!/father.conf
brother
start reads self.conf
sun.misc.CompoundEnumeration@27bc2616
jar:file:/Users/sunyuming/Documents/tool/jars//MySub-1.0.0-jar-with-dependencies.jar!/self.conf
self
jar:file:/Users/sunyuming/Documents/tool/jars//MySubBrother-1.0.0-jar-with-dependencies.jar!/self.conf
brother
start reads brother.conf
sun.misc.CompoundEnumeration@1ddc4ec2
jar:file:/Users/sunyuming/Documents/tool/jars//MySubBrother-1.0.0-jar-with-dependencies.jar!/brother.conf
brother

 

 

 

 

JDBC SPI 类加载机制 JDBC就使用了这种方式遍历当前线程类加载器中所有resources/META-INF/services/下的java.sql.Driver文件