org.apache.cassandra.schema.Types Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of cassandra-all Show documentation
Show all versions of cassandra-all Show documentation
The Apache Cassandra Project develops a highly scalable second-generation distributed database, bringing together Dynamo's fully distributed design and Bigtable's ColumnFamily-based data model.
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.cassandra.schema;
import java.nio.ByteBuffer;
import java.util.*;
import java.util.function.Predicate;
import java.util.stream.Stream;
import java.util.stream.StreamSupport;
import javax.annotation.Nullable;
import com.google.common.collect.*;
import org.apache.cassandra.cql3.FieldIdentifier;
import org.apache.cassandra.cql3.CQL3Type;
import org.apache.cassandra.db.marshal.AbstractType;
import org.apache.cassandra.db.marshal.UserType;
import org.apache.cassandra.exceptions.ConfigurationException;
import static java.lang.String.format;
import static java.util.stream.Collectors.toList;
import static com.google.common.collect.Iterables.any;
import static com.google.common.collect.Iterables.transform;
import static org.apache.cassandra.utils.ByteBufferUtil.bytes;
/**
* An immutable container for a keyspace's UDTs.
*/
public final class Types implements Iterable
{
private static final Types NONE = new Types(ImmutableMap.of());
private final Map types;
private Types(Builder builder)
{
types = builder.types.build();
}
/*
* For use in RawBuilder::build only.
*/
private Types(Map types)
{
this.types = types;
}
public static Builder builder()
{
return new Builder();
}
public static RawBuilder rawBuilder(String keyspace)
{
return new RawBuilder(keyspace);
}
public static Types none()
{
return NONE;
}
public static Types of(UserType... types)
{
return builder().add(types).build();
}
public Iterator iterator()
{
return types.values().iterator();
}
public Stream stream()
{
return StreamSupport.stream(spliterator(), false);
}
/**
* Returns a stream of user types sorted by dependencies
* @return a stream of user types sorted by dependencies
*/
public Stream sortedStream()
{
Set sorted = new LinkedHashSet<>();
types.values().forEach(t -> addUserTypes(t, sorted));
return sorted.stream().map(n -> types.get(n));
}
public Iterable referencingUserType(ByteBuffer name)
{
return Iterables.filter(types.values(), t -> t.referencesUserType(name) && !t.name.equals(name));
}
/**
* Get the type with the specified name
*
* @param name a non-qualified type name
* @return an empty {@link Optional} if the type name is not found; a non-empty optional of {@link UserType} otherwise
*/
public Optional get(ByteBuffer name)
{
return Optional.ofNullable(types.get(name));
}
/**
* Get the type with the specified name
*
* @param name a non-qualified type name
* @return null if the type name is not found; the found {@link UserType} otherwise
*/
@Nullable
public UserType getNullable(ByteBuffer name)
{
return types.get(name);
}
boolean containsType(ByteBuffer name)
{
return types.containsKey(name);
}
Types filter(Predicate predicate)
{
Builder builder = builder();
types.values().stream().filter(predicate).forEach(builder::add);
return builder.build();
}
/**
* Create a Types instance with the provided type added
*/
public Types with(UserType type)
{
if (get(type.name).isPresent())
throw new IllegalStateException(format("Type %s already exists", type.name));
return builder().add(this).add(type).build();
}
/**
* Creates a Types instance with the type with the provided name removed
*/
public Types without(ByteBuffer name)
{
UserType type =
get(name).orElseThrow(() -> new IllegalStateException(format("Type %s doesn't exists", name)));
return without(type);
}
public Types without(UserType type)
{
return filter(t -> t != type);
}
public Types withUpdatedUserType(UserType udt)
{
return any(this, t -> t.referencesUserType(udt.name))
? builder().add(transform(this, t -> t.withUpdatedUserType(udt))).build()
: this;
}
@Override
public boolean equals(Object o)
{
if (this == o)
return true;
if (!(o instanceof Types))
return false;
Types other = (Types) o;
if (types.size() != other.types.size())
return false;
Iterator> thisIter = this.types.entrySet().iterator();
Iterator> otherIter = other.types.entrySet().iterator();
while (thisIter.hasNext())
{
Map.Entry thisNext = thisIter.next();
Map.Entry otherNext = otherIter.next();
if (!thisNext.getKey().equals(otherNext.getKey()))
return false;
if (!thisNext.getValue().equals(otherNext.getValue()))
return false;
}
return true;
}
@Override
public int hashCode()
{
return types.hashCode();
}
@Override
public String toString()
{
return types.values().toString();
}
/**
* Sorts the types by dependencies.
*
* @param types the types to sort
* @return the types sorted by dependencies and names
*/
private static Set sortByDependencies(Collection types)
{
Set sorted = new LinkedHashSet<>();
types.stream().forEach(t -> addUserTypes(t, sorted));
return sorted;
}
/**
* Find all user types used by the specified type and add them to the set.
*
* @param type the type to check for user types.
* @param types the set of UDT names to which to add new user types found in {@code type}. Note that the
* insertion ordering is important and ensures that if a user type A uses another user type B, then B will appear
* before A in iteration order.
*/
private static void addUserTypes(AbstractType type, Set types)
{
// Reach into subtypes first, so that if the type is a UDT, it's dependencies are recreated first.
type.subTypes().forEach(t -> addUserTypes(t, types));
if (type.isUDT())
types.add(((UserType) type).name);
}
public static final class Builder
{
final ImmutableSortedMap.Builder types = ImmutableSortedMap.naturalOrder();
private Builder()
{
}
public Types build()
{
return new Types(this);
}
public Builder add(UserType type)
{
assert type.isMultiCell();
types.put(type.name, type);
return this;
}
public Builder add(UserType... types)
{
for (UserType type : types)
add(type);
return this;
}
public Builder add(Iterable types)
{
types.forEach(this::add);
return this;
}
}
public static final class RawBuilder
{
final String keyspace;
final List definitions;
private RawBuilder(String keyspace)
{
this.keyspace = keyspace;
this.definitions = new ArrayList<>();
}
/**
* Build a Types instance from Raw definitions.
*
* Constructs a DAG of graph dependencies and resolves them 1 by 1 in topological order.
*/
public Types build()
{
if (definitions.isEmpty())
return Types.none();
/*
* build a DAG of UDT dependencies
*/
Map vertices = Maps.newHashMapWithExpectedSize(definitions.size()); // map values are numbers of referenced types
for (RawUDT udt : definitions)
vertices.put(udt, 0);
Multimap adjacencyList = HashMultimap.create();
for (RawUDT udt1 : definitions)
for (RawUDT udt2 : definitions)
if (udt1 != udt2 && udt1.referencesUserType(udt2))
adjacencyList.put(udt2, udt1);
/*
* resolve dependencies in topological order, using Kahn's algorithm
*/
adjacencyList.values().forEach(vertex -> vertices.put(vertex, vertices.get(vertex) + 1));
Queue resolvableTypes = new LinkedList<>(); // UDTs with 0 dependencies
for (Map.Entry entry : vertices.entrySet())
if (entry.getValue() == 0)
resolvableTypes.add(entry.getKey());
Types types = new Types(new HashMap<>());
while (!resolvableTypes.isEmpty())
{
RawUDT vertex = resolvableTypes.remove();
for (RawUDT dependentType : adjacencyList.get(vertex))
if (vertices.replace(dependentType, vertices.get(dependentType) - 1) == 1)
resolvableTypes.add(dependentType);
UserType udt = vertex.prepare(keyspace, types);
types.types.put(udt.name, udt);
}
if (types.types.size() != definitions.size())
throw new ConfigurationException(format("Cannot resolve UDTs for keyspace %s: some types are missing", keyspace));
/*
* return an immutable copy
*/
return Types.builder().add(types).build();
}
public void add(String name, List fieldNames, List fieldTypes)
{
List rawFieldTypes =
fieldTypes.stream()
.map(CQLTypeParser::parseRaw)
.collect(toList());
definitions.add(new RawUDT(name, fieldNames, rawFieldTypes));
}
private static final class RawUDT
{
final String name;
final List fieldNames;
final List fieldTypes;
RawUDT(String name, List fieldNames, List fieldTypes)
{
this.name = name;
this.fieldNames = fieldNames;
this.fieldTypes = fieldTypes;
}
boolean referencesUserType(RawUDT other)
{
return fieldTypes.stream().anyMatch(t -> t.referencesUserType(other.name));
}
UserType prepare(String keyspace, Types types)
{
List preparedFieldNames =
fieldNames.stream()
.map(FieldIdentifier::forInternalString)
.collect(toList());
List> preparedFieldTypes =
fieldTypes.stream()
.map(t -> t.prepareInternal(keyspace, types).getType())
.collect(toList());
return new UserType(keyspace, bytes(name), preparedFieldNames, preparedFieldTypes, true);
}
@Override
public int hashCode()
{
return name.hashCode();
}
@Override
public boolean equals(Object other)
{
return name.equals(((RawUDT) other).name);
}
}
}
static TypesDiff diff(Types before, Types after)
{
return TypesDiff.diff(before, after);
}
static final class TypesDiff extends Diff
{
private static final TypesDiff NONE = new TypesDiff(Types.none(), Types.none(), ImmutableList.of());
private TypesDiff(Types created, Types dropped, ImmutableCollection> altered)
{
super(created, dropped, altered);
}
private static TypesDiff diff(Types before, Types after)
{
if (before == after)
return NONE;
Types created = after.filter(t -> !before.containsType(t.name));
Types dropped = before.filter(t -> !after.containsType(t.name));
ImmutableList.Builder> altered = ImmutableList.builder();
before.forEach(typeBefore ->
{
UserType typeAfter = after.getNullable(typeBefore.name);
if (null != typeAfter)
typeBefore.compare(typeAfter).ifPresent(kind -> altered.add(new Altered<>(typeBefore, typeAfter, kind)));
});
return new TypesDiff(created, dropped, altered.build());
}
}
}