/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.facebook.presto.sql.analyzer;
import com.facebook.presto.spi.type.Type;
import com.facebook.presto.spi.type.TypeSignature;
import com.google.common.collect.ImmutableList;
import java.util.List;
import java.util.function.Function;
import static com.google.common.base.Preconditions.checkState;
import static com.google.common.collect.ImmutableList.toImmutableList;
import static java.util.Objects.requireNonNull;
public class TypeSignatureProvider
{
// hasDependency field exists primarily to make manipulating types without dependencies easy,
// and to make toString more friendly.
private final boolean hasDependency;
private final Function<List<Type>, TypeSignature> typeSignatureResolver;
public TypeSignatureProvider(TypeSignature typeSignature)
{
this.hasDependency = false;
this.typeSignatureResolver = ignored -> typeSignature;
}
public TypeSignatureProvider(Function<List<Type>, TypeSignature> typeSignatureResolver)
{
this.hasDependency = true;
this.typeSignatureResolver = requireNonNull(typeSignatureResolver, "typeSignatureResolver is null");
}
public boolean hasDependency()
{
return hasDependency;
}
public TypeSignature getTypeSignature()
{
checkState(!hasDependency);
return typeSignatureResolver.apply(ImmutableList.of());
}
public TypeSignature getTypeSignature(List<Type> boundTypeParameters)
{
checkState(hasDependency);
return typeSignatureResolver.apply(boundTypeParameters);
}
public static List<TypeSignatureProvider> fromTypes(List<? extends Type> types)
{
return types.stream()
.map(Type::getTypeSignature)
.map(TypeSignatureProvider::new)
.collect(toImmutableList());
}
public static List<TypeSignatureProvider> fromTypeSignatures(List<? extends TypeSignature> typeSignatures)
{
return typeSignatures.stream()
.map(TypeSignatureProvider::new)
.collect(toImmutableList());
}
@Override
public String toString()
{
if (hasDependency) {
return super.toString();
}
return getTypeSignature().toString();
}
}