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.beam.sdk.extensions.sql.meta.provider;
  
  import java.util.Map;
  import org.apache.beam.sdk.extensions.sql.meta.BeamSqlTable;
  import org.apache.beam.sdk.extensions.sql.meta.Table;
  import org.apache.beam.sdk.schemas.Schema;
  import org.apache.beam.vendor.guava.v32_1_2_jre.com.google.common.collect.ImmutableMap;
  
  /**
   * A {@code ReadOnlyTableProvider} provides in-memory read only set of {@code BeamSqlTable
   * BeamSqlTables}.
   */
  @SuppressWarnings({
    "nullness" // TODO(https://github.com/apache/beam/issues/20497)
  })
  public class ReadOnlyTableProvider implements TableProvider {
    private final String typeName;
    private final Map<String, BeamSqlTable> tables;
  
    public ReadOnlyTableProvider(String typeName, Map<String, BeamSqlTable> tables) {
      this.typeName = typeName;
      this.tables = tables;
    }
  
    @Override
    public String getTableType() {
      return typeName;
    }
  
    @Override
    public void createTable(Table table) {
      throw new UnsupportedOperationException(
          "ReadOnlyTableProvider does not support table creation");
    }
  
    @Override
    public void dropTable(String tableName) {
      throw new UnsupportedOperationException(
          "ReadOnlyTableProvider does not support table deletion");
    }
  
    @Override
    public Map<String, Table> getTables() {
      ImmutableMap.Builder<String, Table> map = ImmutableMap.builder();
      for (Map.Entry<String, BeamSqlTable> table : tables.entrySet()) {
        map.put(
            table.getKey(),
            Table.builder()
                .type(getTableType())
                .name(table.getKey())
                .schema(Schema.builder().build())
                .build());
      }
      return map.build();
    }
  
    @Override
    public BeamSqlTable buildBeamSqlTable(Table table) {
      return tables.get(table.getName());
    }
  }
  