HHH-15412 Cleanup: remove reflection keeping JDK8 compatibility afloat in AggregatedServiceLoader

This commit is contained in:
Sanne Grinovero 2022-07-21 11:41:02 +01:00 committed by Sanne Grinovero
parent 83ea2e8f42
commit 68dc79a87a
1 changed files with 7 additions and 98 deletions

View File

@ -6,8 +6,6 @@
*/
package org.hibernate.boot.registry.classloading.internal;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
@ -18,10 +16,8 @@ import java.util.List;
import java.util.ServiceConfigurationError;
import java.util.ServiceLoader;
import java.util.Set;
import java.util.function.Supplier;
import java.util.stream.Stream;
import org.hibernate.AssertionFailure;
import org.hibernate.internal.CoreLogging;
import org.hibernate.internal.CoreMessageLogger;
@ -33,46 +29,9 @@ abstract class AggregatedServiceLoader<S> {
private static final CoreMessageLogger log = CoreLogging.messageLogger( AggregatedServiceLoader.class );
private static final Method SERVICE_LOADER_STREAM_METHOD;
private static final Method PROVIDER_TYPE_METHOD;
static {
Class<?> serviceLoaderClass = ServiceLoader.class;
Method serviceLoaderStreamMethod = null;
Method providerTypeMethod = null;
try {
/*
* JDK 9 introduced the stream() method on ServiceLoader,
* which we need in order to avoid duplicate service instantiation.
* See ClassPathAndModulePathAggregatedServiceLoader.
*/
serviceLoaderStreamMethod = serviceLoaderClass.getMethod( "stream" );
Class<?> providerClass = Class.forName( serviceLoaderClass.getName() + "$Provider" );
providerTypeMethod = providerClass.getMethod( "type" );
}
catch (NoSuchMethodException | ClassNotFoundException e) {
/*
* Probably Java 8.
* Leave the method constants null,
* we will automatically use a service loader implementation that doesn't rely on them.
* See create(...).
*/
}
SERVICE_LOADER_STREAM_METHOD = serviceLoaderStreamMethod;
PROVIDER_TYPE_METHOD = providerTypeMethod;
}
static <S> AggregatedServiceLoader<S> create(AggregatedClassLoader aggregatedClassLoader,
Class<S> serviceContract) {
if ( SERVICE_LOADER_STREAM_METHOD != null ) {
// Java 9+
return new ClassPathAndModulePathAggregatedServiceLoader<>( aggregatedClassLoader, serviceContract );
}
else {
// Java 8
return new ClassPathOnlyAggregatedServiceLoader<>( aggregatedClassLoader, serviceContract );
}
}
/**
@ -85,44 +44,10 @@ abstract class AggregatedServiceLoader<S> {
*/
public abstract void close();
/**
* An {@link AggregatedServiceLoader} that will only detect services defined in the class path,
* not in the module path,
* because it passes the aggregated classloader directly to the service loader.
* <p>
* This implementation is best when running Hibernate ORM on Java 8.
* On Java 9 and above, {@link ClassPathAndModulePathAggregatedServiceLoader} should be used.
*
* @param <S> The type of loaded services.
*/
private static class ClassPathOnlyAggregatedServiceLoader<S> extends AggregatedServiceLoader<S> {
private final ServiceLoader<S> delegate;
private ClassPathOnlyAggregatedServiceLoader(AggregatedClassLoader aggregatedClassLoader, Class<S> serviceContract) {
this.delegate = ServiceLoader.load( serviceContract, aggregatedClassLoader );
}
@Override
public Collection<S> getAll() {
final Set<S> services = new LinkedHashSet<>();
for ( S service : delegate ) {
services.add( service );
}
return services;
}
@Override
public void close() {
// Clear service providers
delegate.reload();
}
}
/**
* An {@link AggregatedServiceLoader} that will detect services defined in the class path or in the module path.
* <p>
* This implementation only works when running Hibernate ORM on Java 9 and above.
* On Java 8, {@link ClassPathOnlyAggregatedServiceLoader} must be used.
* <p>
* When retrieving services from providers in the module path,
* the service loader internally uses a map from classloader to service catalog.
@ -182,7 +107,7 @@ abstract class AggregatedServiceLoader<S> {
* as well as the close() method,
* and also the service loader map in ClassLoaderServiceImpl,
* and we can simply call .reload() on the service loader after we load services
* in ClassPathOnlyAggregatedServiceLoader.getAll().
* in ClassPathAndModulePathAggregatedServiceLoader.getAll().
*/
cache = Collections.unmodifiableCollection( loadAll() );
}
@ -194,9 +119,9 @@ abstract class AggregatedServiceLoader<S> {
Set<S> result = new LinkedHashSet<>();
// Always try the aggregated class loader first
Iterator<? extends Supplier<S>> providerIterator = providerStream( aggregatedClassLoaderServiceLoader ).iterator();
Iterator<ServiceLoader.Provider<S>> providerIterator = aggregatedClassLoaderServiceLoader.stream().iterator();
while ( providerIterator.hasNext() ) {
Supplier<S> provider = providerIterator.next();
ServiceLoader.Provider<S> provider = providerIterator.next();
collectServiceIfNotDuplicate( result, alreadyEncountered, provider );
}
@ -205,7 +130,7 @@ abstract class AggregatedServiceLoader<S> {
* because only them can instantiate services provided by jars in the module path.
*/
for ( ServiceLoader<S> delegate : delegates ) {
providerIterator = providerStream( delegate ).iterator();
providerIterator = delegate.stream().iterator();
/*
* Note that advancing the stream itself can lead to (arguably) "legitimate" errors,
* where we fail to load the service,
@ -216,7 +141,7 @@ abstract class AggregatedServiceLoader<S> {
* See https://hibernate.atlassian.net/browse/HHH-13551.
*/
while ( hasNextIgnoringServiceConfigurationError( providerIterator ) ) {
Supplier<S> provider = providerIterator.next();
ServiceLoader.Provider<S> provider = providerIterator.next();
collectServiceIfNotDuplicate( result, alreadyEncountered, provider );
}
}
@ -224,16 +149,6 @@ abstract class AggregatedServiceLoader<S> {
return result;
}
@SuppressWarnings("unchecked")
private Stream<? extends Supplier<S>> providerStream(ServiceLoader<S> serviceLoader) {
try {
return ( (Stream<? extends Supplier<S>>) SERVICE_LOADER_STREAM_METHOD.invoke( serviceLoader ) );
}
catch (RuntimeException | IllegalAccessException | InvocationTargetException e) {
throw new AssertionFailure( "Error calling ServiceLoader.stream()", e );
}
}
private boolean hasNextIgnoringServiceConfigurationError(Iterator<?> iterator) {
while ( true ) {
try {
@ -262,14 +177,8 @@ abstract class AggregatedServiceLoader<S> {
* and one provider may return different types of services
* depending on conditions known only to itself.
*/
private void collectServiceIfNotDuplicate(Set<S> result, Set<String> alreadyEncountered, Supplier<S> provider) {
Class<?> type;
try {
type = (Class<?>) PROVIDER_TYPE_METHOD.invoke( provider );
}
catch (RuntimeException | IllegalAccessException | InvocationTargetException e) {
throw new AssertionFailure( "Error calling ServiceLoader.Provider.type()", e );
}
private void collectServiceIfNotDuplicate(Set<S> result, Set<String> alreadyEncountered, ServiceLoader.Provider<S> provider) {
final Class<? extends S> type = provider.type();
String typeName = type.getName();
if ( alreadyEncountered.add( typeName ) ) {
result.add( provider.get() );