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
