/*
* Copyright 2013-2014 the original author or authors.
*
* 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 org.springframework.cassandra.core.cql.generator;
import static org.springframework.cassandra.core.cql.CqlStringUtils.*;
import java.util.Map;
import org.springframework.cassandra.core.keyspace.AddColumnSpecification;
import org.springframework.cassandra.core.keyspace.AlterColumnSpecification;
import org.springframework.cassandra.core.keyspace.AlterTableSpecification;
import org.springframework.cassandra.core.keyspace.ColumnChangeSpecification;
import org.springframework.cassandra.core.keyspace.DropColumnSpecification;
import org.springframework.cassandra.core.keyspace.Option;
import org.springframework.cassandra.core.keyspace.RenameColumnSpecification;
import org.springframework.cassandra.core.keyspace.TableOption;
/**
* CQL generator for generating {@code ALTER TABLE} statements.
*
* @author Matthew T. Adams
* @author Mark Paluch
* @see AlterTableSpecification
* @see TableOptionsCqlGenerator
*/
public class AlterTableCqlGenerator extends TableOptionsCqlGenerator<AlterTableSpecification> {
/**
* Generates a CQL statement from the given {@code specification}.
*
* @param specification must not be {@literal null}.
* @return the generated CQL statement.
*/
public static String toCql(AlterTableSpecification specification) {
return new AlterTableCqlGenerator(specification).toCql();
}
/**
* Create a new {@literal {@link AlterTableCqlGenerator}.
*
* @param specification must not be {@literal null}.
*/
public AlterTableCqlGenerator(AlterTableSpecification specification) {
super(specification);
}
@Override
public StringBuilder toCql(StringBuilder cql) {
cql = noNull(cql);
preambleCql(cql);
if (!spec().getChanges().isEmpty()) {
cql.append(' ');
changesCql(cql);
}
if (!spec().getOptions().isEmpty()) {
cql.append(' ');
optionsCql(cql);
}
cql.append(";");
return cql;
}
protected StringBuilder preambleCql(StringBuilder cql) {
return noNull(cql).append("ALTER TABLE ").append(spec().getName());
}
protected StringBuilder changesCql(StringBuilder cql) {
cql = noNull(cql);
boolean first = true;
for (ColumnChangeSpecification change : spec().getChanges()) {
if (first) {
first = false;
} else {
cql.append(" ");
}
getCqlGeneratorFor(change).toCql(cql);
}
return cql;
}
protected ColumnChangeCqlGenerator<?> getCqlGeneratorFor(ColumnChangeSpecification change) {
if (change instanceof AddColumnSpecification) {
return new AddColumnCqlGenerator((AddColumnSpecification) change);
}
if (change instanceof DropColumnSpecification) {
return new DropColumnCqlGenerator((DropColumnSpecification) change);
}
if (change instanceof AlterColumnSpecification) {
return new AlterColumnCqlGenerator((AlterColumnSpecification) change);
}
if (change instanceof RenameColumnSpecification) {
return new RenameColumnCqlGenerator((RenameColumnSpecification) change);
}
throw new IllegalArgumentException("unknown ColumnChangeSpecification type: " + change.getClass().getName());
}
@SuppressWarnings("unchecked")
protected StringBuilder optionsCql(StringBuilder cql) {
cql = noNull(cql);
Map<String, Object> options = spec().getOptions();
if (options == null || options.isEmpty()) {
return cql;
}
cql.append("WITH ");
boolean first = true;
for (String key : options.keySet()) {
/*
* Compact storage is illegal on alter table.
* TODO - Is there a way to handle this in the specification?
*/
if (key.equals(TableOption.COMPACT_STORAGE.getName())) {
throw new IllegalArgumentException("Alter table cannot contain the COMPACT STORAGE option");
}
if (first) {
first = false;
} else {
cql.append(" AND ");
}
cql.append(key);
Object value = options.get(key);
if (value == null) {
continue;
}
cql.append(" = ");
if (value instanceof Map) {
optionValueMap((Map<Option, Object>) value, cql);
continue;
}
// else just use value as string
cql.append(value.toString());
}
return cql;
}
}