ExceptionMapperFactory.java
/*
* Copyright (c) 2010, 2023 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
package org.glassfish.jersey.internal;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Proxy;
import java.lang.reflect.Type;
import java.lang.reflect.TypeVariable;
import java.util.Collection;
import java.util.LinkedHashSet;
import java.util.Set;
import java.util.SortedSet;
import java.util.TreeSet;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.ws.rs.Priorities;
import javax.ws.rs.ProcessingException;
import javax.ws.rs.ext.ExceptionMapper;
import org.glassfish.jersey.JerseyPriorities;
import org.glassfish.jersey.internal.inject.Bindings;
import org.glassfish.jersey.internal.inject.InjectionManager;
import org.glassfish.jersey.internal.inject.InstanceBinding;
import org.glassfish.jersey.internal.inject.Providers;
import org.glassfish.jersey.internal.inject.ServiceHolder;
import org.glassfish.jersey.internal.util.ReflectionHelper;
import org.glassfish.jersey.internal.util.collection.ClassTypePair;
import org.glassfish.jersey.internal.util.collection.LazyValue;
import org.glassfish.jersey.internal.util.collection.Value;
import org.glassfish.jersey.internal.util.collection.Values;
import org.glassfish.jersey.spi.ExceptionMappers;
import org.glassfish.jersey.spi.ExtendedExceptionMapper;
/**
* {@link ExceptionMappers Exception mappers} implementation that aggregates
* exception mappers and server as the main entry point for exception mapper
* instance lookup.
*
* @author Paul Sandoz
* @author Santiago Pericas-Geertsen (Santiago.PericasGeertsen at oracle.com)
* @author Marek Potociar
* @author Jakub Podlesak
*/
public class ExceptionMapperFactory implements ExceptionMappers {
private static final Logger LOGGER = Logger.getLogger(ExceptionMapperFactory.class.getName());
/**
* Configurator which initializes and register {@link ExceptionMappers} instance into {@link InjectionManager} and
* {@link BootstrapBag}.
*
* @author Petr Bouda
*/
public static class ExceptionMappersConfigurator implements BootstrapConfigurator {
private ExceptionMapperFactory exceptionMapperFactory;
@Override
public void init(InjectionManager injectionManager, BootstrapBag bootstrapBag) {
exceptionMapperFactory = new ExceptionMapperFactory(injectionManager);
InstanceBinding<ExceptionMapperFactory> binding =
Bindings.service(exceptionMapperFactory)
.to(ExceptionMappers.class);
injectionManager.register(binding);
}
@Override
public void postInit(InjectionManager injectionManager, BootstrapBag bootstrapBag) {
bootstrapBag.setExceptionMappers(exceptionMapperFactory);
}
}
private static class ExceptionMapperType {
ServiceHolder<ExceptionMapper> mapper;
Class<? extends Throwable> exceptionType;
public ExceptionMapperType(final ServiceHolder<ExceptionMapper> mapper, final Class<? extends Throwable> exceptionType) {
this.mapper = mapper;
this.exceptionType = exceptionType;
}
}
private final Value<Set<ExceptionMapperType>> exceptionMapperTypes;
@Override
@SuppressWarnings("unchecked")
public <T extends Throwable> ExceptionMapper<T> findMapping(final T exceptionInstance) {
return find((Class<T>) exceptionInstance.getClass(), exceptionInstance);
}
@Override
public <T extends Throwable> ExceptionMapper<T> find(final Class<T> type) {
return find(type, null);
}
@SuppressWarnings("unchecked")
private <T extends Throwable> ExceptionMapper<T> find(final Class<T> type, final T exceptionInstance) {
ExceptionMapper<T> mapper = null;
int minDistance = Integer.MAX_VALUE;
int priority = Priorities.USER;
for (final ExceptionMapperType mapperType : exceptionMapperTypes.get()) {
final int d = distance(type, mapperType.exceptionType);
if (d >= 0 && d <= minDistance) {
final ExceptionMapper<T> candidate = mapperType.mapper.getInstance();
final int p = mapperType.mapper.getRank() > 0 ? mapperType.mapper.getRank() : Priorities.USER;
if (isPreferredCandidate(exceptionInstance, candidate, d == minDistance && p >= priority)) {
mapper = candidate;
minDistance = d;
priority = p;
}
}
}
return mapper;
}
/**
* Determines whether the currently considered candidate should be preferred over the previous one.
*
* @param exceptionInstance exception to be mapped.
* @param candidate mapper able to map given exception type.
* @param sameDistance flag indicating whether this and the previously considered candidate are in the same distance.
* @param <T> exception type.
* @return {@code true} if the given candidate is preferred over the previous one with the same or lower distance,
* {@code false} otherwise.
*/
private <T extends Throwable> boolean isPreferredCandidate(final T exceptionInstance, final ExceptionMapper<T> candidate,
final boolean sameDistance) {
if (exceptionInstance == null) {
return true;
}
if (candidate instanceof ExtendedExceptionMapper) {
return !sameDistance
&& ((ExtendedExceptionMapper<T>) candidate).isMappable(exceptionInstance);
} else {
return !sameDistance;
}
}
/**
* Create new exception mapper factory initialized with {@link InjectionManager injection manager}
* instance that will be used to look up all providers implementing {@link ExceptionMapper} interface.
*
* @param injectionManager injection manager.
*/
public ExceptionMapperFactory(InjectionManager injectionManager) {
exceptionMapperTypes = createLazyExceptionMappers(injectionManager);
}
/**
* Returns {@link LazyValue} of exception mappers that delays their creation to the first use. The exception mappers won't be
* created during bootstrap but at the time of the first call.
*
* @param injectionManager injection manager that may not be fully populated at the time of a function call therefore the
* result is wrapped to lazy value.
* @return lazy value of exception mappers.
*/
private LazyValue<Set<ExceptionMapperType>> createLazyExceptionMappers(InjectionManager injectionManager) {
return Values.lazy((Value<Set<ExceptionMapperType>>) () -> {
Collection<ServiceHolder<ExceptionMapper>> mapperHandles =
Providers.getAllServiceHolders(injectionManager, ExceptionMapper.class);
Set<ExceptionMapperType> exceptionMapperTypes = new LinkedHashSet<>();
for (ServiceHolder<ExceptionMapper> mapperHandle: mapperHandles) {
ExceptionMapper mapper = mapperHandle.getInstance();
if (Proxy.isProxyClass(mapper.getClass())) {
SortedSet<Class<? extends ExceptionMapper>> mapperTypes =
new TreeSet<>((o1, o2) -> o1.isAssignableFrom(o2) ? -1 : 1);
Set<Type> contracts = mapperHandle.getContractTypes();
for (final Type contract : contracts) {
if (contract instanceof Class
&& ExceptionMapper.class.isAssignableFrom((Class<?>) contract)
&& contract != ExceptionMapper.class) {
//noinspection unchecked
mapperTypes.add((Class<? extends ExceptionMapper>) contract);
}
}
if (!mapperTypes.isEmpty()) {
final Class<? extends Throwable> c = getExceptionType(mapperTypes.first());
if (c != null) {
exceptionMapperTypes.add(new ExceptionMapperType(mapperHandle, c));
}
}
} else {
final Class<? extends Throwable> c = getExceptionType(mapper.getClass());
if (c != null) {
exceptionMapperTypes.add(new ExceptionMapperType(mapperHandle, c));
}
}
}
return exceptionMapperTypes;
});
}
private int distance(Class<?> c, final Class<?> emtc) {
int distance = 0;
if (!emtc.isAssignableFrom(c)) {
return -1;
}
while (c != emtc) {
c = c.getSuperclass();
distance++;
}
return distance;
}
@SuppressWarnings("unchecked")
private Class<? extends Throwable> getExceptionType(final Class<? extends ExceptionMapper> c) {
final Class<?> t = getType(c);
if (Throwable.class.isAssignableFrom(t)) {
return (Class<? extends Throwable>) t;
}
if (LOGGER.isLoggable(Level.WARNING)) {
LOGGER.warning(LocalizationMessages.EXCEPTION_MAPPER_SUPPORTED_TYPE_UNKNOWN(c.getName()));
}
return null;
}
/**
* Get exception type for given exception mapper class.
*
* @param clazz class to get exception type for.
* @return exception type for given class.
*/
private Class getType(final Class<? extends ExceptionMapper> clazz) {
Class clazzHolder = clazz;
while (clazzHolder != Object.class) {
final Class type = getTypeFromInterface(clazzHolder, clazz);
if (type != null) {
return type;
}
clazzHolder = clazzHolder.getSuperclass();
}
throw new ProcessingException(LocalizationMessages.ERROR_FINDING_EXCEPTION_MAPPER_TYPE(clazz));
}
/**
* Iterate through interface hierarchy of {@code clazz} and get exception type for given class.
*
* @param clazz class to inspect.
* @return exception type for given class or {@code null} if the class doesn't implement {@code ExceptionMapper}.
*/
private Class getTypeFromInterface(Class<?> clazz, final Class<? extends ExceptionMapper> original) {
final Type[] types = clazz.getGenericInterfaces();
for (final Type type : types) {
if (type instanceof ParameterizedType) {
final ParameterizedType pt = (ParameterizedType) type;
if (pt.getRawType() == ExceptionMapper.class
|| pt.getRawType() == ExtendedExceptionMapper.class) {
return getResolvedType(pt.getActualTypeArguments()[0], original, clazz);
}
} else if (type instanceof Class<?>) {
clazz = (Class<?>) type;
if (ExceptionMapper.class.isAssignableFrom(clazz)) {
return getTypeFromInterface(clazz, original);
}
}
}
return null;
}
private Class getResolvedType(final Type t, final Class c, final Class dc) {
if (t instanceof Class) {
return (Class) t;
} else if (t instanceof TypeVariable) {
final ClassTypePair ct = ReflectionHelper.resolveTypeVariable(c, dc, (TypeVariable) t);
if (ct != null) {
return ct.rawClass();
} else {
return null;
}
} else if (t instanceof ParameterizedType) {
final ParameterizedType pt = (ParameterizedType) t;
return (Class) pt.getRawType();
} else {
return null;
}
}
}