content: /*
   * 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.calcite.adapter.jdbc;
  
  import org.apache.calcite.linq4j.tree.Expression;
  import org.apache.calcite.rel.type.RelProtoDataType;
  import org.apache.calcite.schema.Function;
  import org.apache.calcite.schema.Schema;
  import org.apache.calcite.schema.SchemaPlus;
  import org.apache.calcite.schema.SchemaVersion;
  import org.apache.calcite.schema.Schemas;
  import org.apache.calcite.schema.Table;
  import org.apache.calcite.schema.lookup.LikePattern;
  import org.apache.calcite.schema.lookup.Lookup;
  
  import org.checkerframework.checker.nullness.qual.Nullable;
  
  import java.util.Collection;
  import java.util.Collections;
  import java.util.Set;
  
  import static java.util.Objects.requireNonNull;
  
  /**
   * Base class for JDBC schemas.
   */
  public abstract class JdbcBaseSchema implements Schema {
  
    @Override public abstract Lookup<Table> tables();
  
  
    @Deprecated @Override public @Nullable Table getTable(String name) {
      return tables().get(name);
    }
  
    @Deprecated @Override public Set<String> getTableNames() {
      return tables().getNames(LikePattern.any());
    }
  
    @Override public abstract Lookup<? extends Schema> subSchemas();
  
    @Deprecated @Override public @Nullable Schema getSubSchema(String name) {
      return subSchemas().get(name);
    }
  
    @Deprecated @Override public Set<String> getSubSchemaNames() {
      return subSchemas().getNames(LikePattern.any());
    }
  
  
    @Override public @Nullable RelProtoDataType getType(String name) {
      return null;
    }
  
    @Override public Set<String> getTypeNames() {
      return Collections.emptySet();
    }
  
    @Override public final Collection<Function> getFunctions(String name) {
      return Collections.emptyList();
    }
  
    @Override public final Set<String> getFunctionNames() {
      return Collections.emptySet();
    }
  
    @Override public Expression getExpression(final @Nullable SchemaPlus parentSchema,
        final String name) {
      requireNonNull(parentSchema, "parentSchema");
      return Schemas.subSchemaExpression(parentSchema, name, getClass());
    }
  
    @Override public boolean isMutable() {
      return false;
    }
  
    @Override public Schema snapshot(final SchemaVersion version) {
      return this;
    }
  }
  