com.hazelcast.org.apache.calcite.adapter.jdbc.JdbcCatalogSchema Maven / Gradle / Ivy
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* 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 com.hazelcast.org.apache.calcite.adapter.jdbc;
import com.hazelcast.org.apache.calcite.DataContext;
import com.hazelcast.org.apache.calcite.linq4j.tree.Expression;
import com.hazelcast.org.apache.calcite.linq4j.tree.Expressions;
import com.hazelcast.org.apache.calcite.schema.Schema;
import com.hazelcast.org.apache.calcite.schema.SchemaPlus;
import com.hazelcast.org.apache.calcite.schema.Schemas;
import com.hazelcast.org.apache.calcite.schema.impl.AbstractSchema;
import com.hazelcast.org.apache.calcite.sql.SqlDialect;
import com.hazelcast.org.apache.calcite.sql.SqlDialectFactory;
import com.hazelcast.org.apache.calcite.sql.SqlDialectFactoryImpl;
import com.hazelcast.org.apache.calcite.util.BuiltInMethod;
import com.hazelcast.com.google.common.base.Supplier;
import com.hazelcast.com.google.common.base.Suppliers;
import com.hazelcast.com.google.common.collect.ImmutableMap;
import com.hazelcast.org.checkerframework.checker.nullness.qual.Nullable;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Map;
import javax.sql.DataSource;
import static java.util.Objects.requireNonNull;
/**
* Schema based upon a JDBC catalog (database).
*
* This schema does not directly contain tables, but contains a sub-schema
* for each schema in the catalog in the back-end. Each of those sub-schemas is
* an instance of {@link JdbcSchema}.
*
*
This schema is lazy: it does not compute the list of schema names until
* the first call to {@link #getSubSchemaMap()}. Then it creates a
* {@link JdbcSchema} for each schema name. Each JdbcSchema will populate its
* tables on demand.
*/
public class JdbcCatalogSchema extends AbstractSchema {
final DataSource dataSource;
public final SqlDialect dialect;
final JdbcConvention convention;
final String catalog;
/** Sub-schemas by name, lazily initialized. */
@SuppressWarnings("method.invocation.invalid")
final Supplier subSchemaMapSupplier =
Suppliers.memoize(() -> computeSubSchemaMap());
/** Creates a JdbcCatalogSchema. */
public JdbcCatalogSchema(DataSource dataSource, SqlDialect dialect,
JdbcConvention convention, String catalog) {
this.dataSource = requireNonNull(dataSource, "dataSource");
this.dialect = requireNonNull(dialect, "dialect");
this.convention = requireNonNull(convention, "convention");
this.catalog = catalog;
}
public static JdbcCatalogSchema create(
@Nullable SchemaPlus parentSchema,
String name,
DataSource dataSource,
String catalog) {
return create(parentSchema, name, dataSource,
SqlDialectFactoryImpl.INSTANCE, catalog);
}
public static JdbcCatalogSchema create(
@Nullable SchemaPlus parentSchema,
String name,
DataSource dataSource,
SqlDialectFactory dialectFactory,
String catalog) {
final Expression expression =
parentSchema != null
? Schemas.subSchemaExpression(parentSchema, name,
JdbcCatalogSchema.class)
: Expressions.call(DataContext.ROOT,
BuiltInMethod.DATA_CONTEXT_GET_ROOT_SCHEMA.method);
final SqlDialect dialect =
JdbcSchema.createDialect(dialectFactory, dataSource);
final JdbcConvention convention =
JdbcConvention.of(dialect, expression, name);
return new JdbcCatalogSchema(dataSource, dialect, convention, catalog);
}
private SubSchemaMap computeSubSchemaMap() {
final ImmutableMap.Builder builder =
ImmutableMap.builder();
String defaultSchemaName;
try (Connection connection = dataSource.getConnection();
ResultSet resultSet =
connection.getMetaData().getSchemas(catalog, null)) {
defaultSchemaName = connection.getSchema();
while (resultSet.next()) {
final String schemaName = requireNonNull(
resultSet.getString(1),
() -> "got null schemaName from the database");
builder.put(schemaName,
new JdbcSchema(dataSource, dialect, convention, catalog, schemaName));
}
} catch (SQLException e) {
throw new RuntimeException(e);
}
return new SubSchemaMap(defaultSchemaName, builder.build());
}
@Override protected Map getSubSchemaMap() {
return subSchemaMapSupplier.get().map;
}
/** Returns the name of the default sub-schema. */
public String getDefaultSubSchemaName() {
return subSchemaMapSupplier.get().defaultSchemaName;
}
/** Returns the data source. */
public DataSource getDataSource() {
return dataSource;
}
/** Contains sub-schemas by name, and the name of the default schema. */
private static class SubSchemaMap {
final String defaultSchemaName;
final ImmutableMap map;
private SubSchemaMap(String defaultSchemaName,
ImmutableMap map) {
this.defaultSchemaName = defaultSchemaName;
this.map = map;
}
}
}