@@ -27,8 +27,11 @@
***** END LICENSE BLOCK *****/
package org .jruby .runtime .load ;
import jnr .posix .JavaSecuredFile ;
import org .jruby .Ruby ;
import java .net .URL ;
/**
* The ClassExtensionLibrary wraps a class which implements BasicLibraryService,
* and when asked to load the service, does a basicLoad of the BasicLibraryService.
@@ -41,40 +44,121 @@ public class ClassExtensionLibrary implements Library {
private final Class theClass ;
private final String name ;
/**
* Try to locate an extension service in the current classloader resources. This happens
* after the jar has been added to JRuby's URLClassLoader (JRubyClassLoader) and is how
* extensions can magically load.
*
* The basic logic is to use the require name (@param searchName) to build the name of
* a class ending in "Service", and then invoke that class to boot the extension.
*
* The looping logic here was in response to a RubyGems change that started absolutizing
* the path to the extension jar under some circumstances, leading to an incorrect
* package/class name for the service contained therein. The new logic will try
* successively more trailing elements until one of them is not a valid package
* name or all elements have been exhausted.
*
* @param runtime the current JRuby runtime
* @param searchName the name passed to `require`
* @return a ClassExtensionLibrary that will boot the ext, or null if none was found
*/
static ClassExtensionLibrary tryFind (Ruby runtime , String searchName ) {
// Create package name, by splitting on / and joining all but the last elements with a ".", and downcasing them.
String [] all = searchName .split ("/" );
StringBuilder finName = new StringBuilder ();
for (int i =0 , j =(all .length -1 ); i <j ; i ++) {
finName .append (all [i ].toLowerCase ()).append ("." );
}
try {
// Make the class name look nice, by splitting on _ and capitalize each segment, then joining
// the, together without anything separating them, and last put on "Service" at the end.
String [] last = all [all .length -1 ].split ("_" );
for (int i =0 , j =last .length ; i <j ; i ++) {
if ("" .equals (last [i ])) break ;
finName .append (Character .toUpperCase (last [i ].charAt (0 ))).append (last [i ].substring (1 ));
// Create package name, by splitting on / and successively accumulating elements to form a class name
String [] elts = searchName .split ("/" );
boolean isAbsolute = new JavaSecuredFile (searchName ).isAbsolute ();
String simpleName = buildSimpleName (elts [elts .length - 1 ]);
int firstElement = isAbsolute ? elts .length - 1 : 0 ;
for (; firstElement >= 0 ; firstElement --) {
String className = buildClassName (elts , firstElement , elts .length - 1 , simpleName );
ClassExtensionLibrary library = tryServiceLoad (runtime , className );
if (library != null ) return library ;
}
return null ;
}
/**
* Build the "simple" part of a service class name from the given require path element
* by splitting on "_" and concatenating as CamelCase, plus "Service" suffix.
*
* @param element the element from which to build a simple service class name
* @return the resulting simple service class name
*/
private static String buildSimpleName (String element ) {
StringBuilder nameBuilder = new StringBuilder (element .length () + "Service" .length ());
String [] last = element .split ("_" );
for (String part : last ) {
if (part .isEmpty ()) break ;
nameBuilder
.append (Character .toUpperCase (part .charAt (0 )))
.append (part , 1 , part .length ());
}
nameBuilder .append ("Service" );
return nameBuilder .toString ();
}
/**
* Build the full class name for a service by joining the specified package elements
* with '.' and appending the given simple class name.
*
* @param elts the array from which to retrieve the package elements
* @param firstElement the first element to use
* @param end the end index at which to stop building the package name
* @param simpleName the simple class name for the service
* @return the full class name for the service
*/
private static String buildClassName (String [] elts , int firstElement , int end , String simpleName ) {
StringBuilder nameBuilder = new StringBuilder ();
for (int offset = firstElement ; offset < end ; offset ++) {
// avoid blank elements from leading or double slashes
if (elts [offset ].isEmpty ()) continue ;
nameBuilder
.append (elts [offset ].toLowerCase ())
.append ('.' );
}
finName .append ("Service" );
// We don't want a package name beginning with dots, so we remove them
String className = finName .toString ().replaceAll ("^\\.*" ,"" );
nameBuilder .append (simpleName );
// quietly try to load the class
Class theClass = runtime .getJavaSupport ().loadJavaClass (className );
return new ClassExtensionLibrary (className + ".java" , theClass );
} catch (ClassNotFoundException cnfe ) {
if (runtime .isDebug ()) cnfe .printStackTrace ();
return nameBuilder .toString ();
}
/**
* Try loading the given service class. Rather than raise ClassNotFoundException for
* jars that do not contain any service class, we require that the service class be a
* "normal" .class file accessible as a classloader resource. If it can be found
* using ClassLoader.getResource, we proceed to attempt to load it as a class.
*
* @param runtime the Ruby runtime into which the extension service will load
* @param className the class name of the service class
* @return a ClassExtensionLibrary if the service class was found; null otherwise.
*/
private static ClassExtensionLibrary tryServiceLoad (Ruby runtime , String className ) {
String classFile = className .replaceAll ("\\." , "/" ) + ".class" ;
try {
// quietly try to load the class, which must be reachable as a .class resource
URL resource = runtime .getJRubyClassLoader ().getResource (classFile );
if (resource != null ) {
Class theClass = runtime .getJavaSupport ().loadJavaClass (className );
return new ClassExtensionLibrary (className + ".java" , theClass );
}
} catch (ClassNotFoundException cnfe ) {
if (runtime .isDebug ()) cnfe .printStackTrace ();
} catch (UnsupportedClassVersionError ucve ) {
if (runtime .isDebug ()) ucve .printStackTrace ();
throw runtime .newLoadError ("JRuby ext built for wrong Java version in `" + className + "': " + ucve , className );
}
// So apparently the class doesn't exist
// The class doesn't exist
return null ;
} catch (UnsupportedClassVersionError ucve ) {
if (runtime .isDebug ()) ucve .printStackTrace ();
throw runtime .newLoadError ("JRuby ext built for wrong Java version in `" + finName + "': " + ucve , finName .toString ());
}
}
public ClassExtensionLibrary (String name , Class extension ) {
