/*
* Minecraft Forge
* Copyright (c) 2016.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation version 2.1
* of the License.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
package net.minecraftforge.common.capabilities;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.IdentityHashMap;
import java.util.List;
import java.util.concurrent.Callable;
import org.apache.logging.log4j.Level;
import org.objectweb.asm.Type;
import com.google.common.base.Function;
import com.google.common.base.Preconditions;
import com.google.common.base.Throwables;
import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
import net.minecraftforge.common.util.EnumHelper;
import net.minecraftforge.fml.common.FMLLog;
import net.minecraftforge.fml.common.discovery.ASMDataTable;
import javax.annotation.Nullable;
public enum CapabilityManager
{
INSTANCE;
/**
* Registers a capability to be consumed by others.
* APIs who define the capability should call this.
* To retrieve the Capability instance, use the @CapabilityInject annotation.
*
* @param type The Interface to be registered
* @param storage A default implementation of the storage handler.
* @param implementation A default implementation of the interface.
*/
public <T> void register(Class<T> type, Capability.IStorage<T> storage, final Class<? extends T> implementation)
{
Preconditions.checkArgument(implementation != null, "Attempted to register a capability with no default implementation");
register(type, storage, new Callable<T>()
{
@Override
public T call() throws Exception
{
try {
return implementation.newInstance();
} catch (InstantiationException e) {
throw Throwables.propagate(e);
} catch (IllegalAccessException e) {
throw Throwables.propagate(e);
}
}
});
}
/**
* Registers a capability to be consumed by others.
* APIs who define the capability should call this.
* To retrieve the Capability instance, use the @CapabilityInject annotation.
*
* @param type The Interface to be registered
* @param storage A default implementation of the storage handler.
* @param factory A Factory that will produce new instances of the default implementation.
*/
public <T> void register(Class<T> type, Capability.IStorage<T> storage, Callable<? extends T> factory)
{
Preconditions.checkArgument(type != null, "Attempted to register a capability with invalid type");
Preconditions.checkArgument(storage != null, "Attempted to register a capability with no storage implementation");
Preconditions.checkArgument(factory != null, "Attempted to register a capability with no default implementation factory");
String realName = type.getName().intern();
Preconditions.checkState(!providers.containsKey(realName), "Can not register a capability implementation multiple times: %s", realName);
Capability<T> cap = new Capability<T>(realName, storage, factory);
providers.put(realName, cap);
List<Function<Capability<?>, Object>> list = callbacks.get(realName);
if (list != null)
{
for (Function<Capability<?>, Object> func : list)
{
func.apply(cap);
}
}
}
// INTERNAL
private IdentityHashMap<String, Capability<?>> providers = Maps.newIdentityHashMap();
private IdentityHashMap<String, List<Function<Capability<?>, Object>>> callbacks = Maps.newIdentityHashMap();
public void injectCapabilities(ASMDataTable data)
{
for (ASMDataTable.ASMData entry : data.getAll(CapabilityInject.class.getName()))
{
final String targetClass = entry.getClassName();
final String targetName = entry.getObjectName();
Type type = (Type)entry.getAnnotationInfo().get("value");
if (type == null)
{
FMLLog.log(Level.WARN, "Unable to inject capability at %s.%s (Invalid Annotation)", targetClass, targetName);
continue;
}
final String capabilityName = type.getInternalName().replace('/', '.').intern();
List<Function<Capability<?>, Object>> list = callbacks.get(capabilityName);
if (list == null)
{
list = Lists.newArrayList();
callbacks.put(capabilityName, list);
}
if (entry.getObjectName().indexOf('(') > 0)
{
list.add(new Function<Capability<?>, Object>()
{
@Override
public Object apply(Capability<?> input)
{
try
{
for (Method mtd : Class.forName(targetClass).getDeclaredMethods())
{
if (targetName.equals(mtd.getName() + Type.getMethodDescriptor(mtd)))
{
if ((mtd.getModifiers() & Modifier.STATIC) != Modifier.STATIC)
{
FMLLog.log(Level.WARN, "Unable to inject capability %s at %s.%s (Non-Static)", capabilityName, targetClass, targetName);
return null;
}
mtd.setAccessible(true);
mtd.invoke(null, input);
return null;
}
}
FMLLog.log(Level.WARN, "Unable to inject capability %s at %s.%s (Method Not Found)", capabilityName, targetClass, targetName);
}
catch (Exception e)
{
FMLLog.log(Level.WARN, e, "Unable to inject capability %s at %s.%s", capabilityName, targetClass, targetName);
}
return null;
}
});
}
else
{
list.add(new Function<Capability<?>, Object>()
{
@Override
public Object apply(Capability<?> input)
{
try
{
Field field = Class.forName(targetClass).getDeclaredField(targetName);
if ((field.getModifiers() & Modifier.STATIC) != Modifier.STATIC)
{
FMLLog.log(Level.WARN, "Unable to inject capability %s at %s.%s (Non-Static)", capabilityName, targetClass, targetName);
return null;
}
EnumHelper.setFailsafeFieldValue(field, null, input);
}
catch (Exception e)
{
FMLLog.log(Level.WARN, e, "Unable to inject capability %s at %s.%s", capabilityName, targetClass, targetName);
}
return null;
}
});
}
}
}
}