/*
* Copyright 2002-2008 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.jdbc.support;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import org.springframework.dao.DataRetrievalFailureException;
import org.springframework.dao.InvalidDataAccessApiUsageException;
/**
* Default implementation of the {@link KeyHolder} interface, to be used for
* holding auto-generated keys (as potentially returned by JDBC insert statements).
*
* <p>Create an instance of this class for each insert operation, and pass
* it to the corresponding {@link org.springframework.jdbc.core.JdbcTemplate}
* or {org.springframework.jdbc.object.SqlUpdate} methods.
*
* @author Thomas Risberg
* @author Juergen Hoeller
* @since 1.1
*/
public class GeneratedKeyHolder implements KeyHolder {
private final List<Map<String, Object>> keyList;
/**
* Create a new GeneratedKeyHolder with a default list.
*/
public GeneratedKeyHolder() {
this.keyList = new LinkedList<Map<String, Object>>();
}
/**
* Create a new GeneratedKeyHolder with a given list.
* @param keyList a list to hold maps of keys
*/
public GeneratedKeyHolder(List<Map<String, Object>> keyList) {
this.keyList = keyList;
}
public Number getKey() throws InvalidDataAccessApiUsageException, DataRetrievalFailureException {
if (this.keyList.size() == 0) {
return null;
}
if (this.keyList.size() > 1 || this.keyList.get(0).size() > 1) {
throw new InvalidDataAccessApiUsageException(
"The getKey method should only be used when a single key is returned. " +
"The current key entry contains multiple keys: " + this.keyList);
}
Iterator<Object> keyIter = this.keyList.get(0).values().iterator();
if (keyIter.hasNext()) {
Object key = keyIter.next();
if (!(key instanceof Number)) {
throw new DataRetrievalFailureException(
"The generated key is not of a supported numeric type. " +
"Unable to cast [" + (key != null ? key.getClass().getName() : null) +
"] to [" + Number.class.getName() + "]");
}
return (Number) key;
}
else {
throw new DataRetrievalFailureException("Unable to retrieve the generated key. " +
"Check that the table has an identity column enabled.");
}
}
public Map<String, Object> getKeys() throws InvalidDataAccessApiUsageException {
if (this.keyList.size() == 0) {
return null;
}
if (this.keyList.size() > 1)
throw new InvalidDataAccessApiUsageException(
"The getKeys method should only be used when keys for a single row are returned. " +
"The current key list contains keys for multiple rows: " + this.keyList);
return this.keyList.get(0);
}
public List<Map<String, Object>> getKeyList() {
return this.keyList;
}
}
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