org.springframework.batch.item.database.builder.HibernatePagingItemReaderBuilder Maven / Gradle / Ivy
/*
* Copyright 2017-2018 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
*
* https://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.batch.item.database.builder;
import java.util.Map;
import org.hibernate.SessionFactory;
import org.springframework.batch.item.database.HibernatePagingItemReader;
import org.springframework.batch.item.database.orm.HibernateQueryProvider;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;
/**
* A builder for the {@link HibernatePagingItemReader}. When configuring, only one of the
* following should be provided:
*
* - {@link #queryString(String)}
* - {@link #queryName(String)}
* - {@link #queryProvider(HibernateQueryProvider)}
*
*
* @author Michael Minella
* @author Glenn Renfro
* @author Mahmoud Ben Hassine
* @since 4.0
* @see HibernatePagingItemReader
*/
public class HibernatePagingItemReaderBuilder {
private int pageSize = 10;
private Map parameterValues;
private String queryName;
private int fetchSize;
private HibernateQueryProvider queryProvider;
private String queryString;
private SessionFactory sessionFactory;
private boolean statelessSession = true;
private boolean saveState = true;
private String name;
private int maxItemCount = Integer.MAX_VALUE;
private int currentItemCount;
/**
* Configure if the state of the {@link org.springframework.batch.item.ItemStreamSupport}
* should be persisted within the {@link org.springframework.batch.item.ExecutionContext}
* for restart purposes.
*
* @param saveState defaults to true
* @return The current instance of the builder.
*/
public HibernatePagingItemReaderBuilder saveState(boolean saveState) {
this.saveState = saveState;
return this;
}
/**
* The name used to calculate the key within the
* {@link org.springframework.batch.item.ExecutionContext}. Required if
* {@link #saveState(boolean)} is set to true.
*
* @param name name of the reader instance
* @return The current instance of the builder.
* @see org.springframework.batch.item.ItemStreamSupport#setName(String)
*/
public HibernatePagingItemReaderBuilder name(String name) {
this.name = name;
return this;
}
/**
* Configure the max number of items to be read.
*
* @param maxItemCount the max items to be read
* @return The current instance of the builder.
* @see org.springframework.batch.item.support.AbstractItemCountingItemStreamItemReader#setMaxItemCount(int)
*/
public HibernatePagingItemReaderBuilder maxItemCount(int maxItemCount) {
this.maxItemCount = maxItemCount;
return this;
}
/**
* Index for the current item. Used on restarts to indicate where to start from.
*
* @param currentItemCount current index
* @return this instance for method chaining
* @see org.springframework.batch.item.support.AbstractItemCountingItemStreamItemReader#setCurrentItemCount(int)
*/
public HibernatePagingItemReaderBuilder currentItemCount(int currentItemCount) {
this.currentItemCount = currentItemCount;
return this;
}
/**
* The number of records to request per page/query. Defaults to 10. Must be greater
* than zero.
*
* @param pageSize number of items
* @return this instance for method chaining
* @see HibernatePagingItemReader#setPageSize(int)
*/
public HibernatePagingItemReaderBuilder pageSize(int pageSize) {
this.pageSize = pageSize;
return this;
}
/**
* A map of parameter values to be set on the query. The key of the map is the name
* of the parameter to be set with the value being the value to be set.
*
* @param parameterValues map of values
* @return this instance for method chaining
* @see HibernatePagingItemReader#setParameterValues(Map)
*/
public HibernatePagingItemReaderBuilder parameterValues(Map parameterValues) {
this.parameterValues = parameterValues;
return this;
}
/**
* The name of the Hibernate named query to be executed for this reader.
*
* @param queryName name of the query to execute
* @return this instance for method chaining
* @see HibernatePagingItemReader#setQueryName(String)
*/
public HibernatePagingItemReaderBuilder queryName(String queryName) {
this.queryName = queryName;
return this;
}
/**
* Fetch size used internally by Hibernate to limit amount of data fetched
* from database per round trip.
*
* @param fetchSize number of records
* @return this instance for method chaining
* @see HibernatePagingItemReader#setFetchSize(int)
*/
public HibernatePagingItemReaderBuilder fetchSize(int fetchSize) {
this.fetchSize = fetchSize;
return this;
}
/**
* A query provider. This should be set only if {@link #queryString(String)} and
* {@link #queryName(String)} have not been set.
*
* @param queryProvider the query provider
* @return this instance for method chaining
* @see HibernatePagingItemReader#setQueryProvider(HibernateQueryProvider)
*/
public HibernatePagingItemReaderBuilder queryProvider(HibernateQueryProvider queryProvider) {
this.queryProvider = queryProvider;
return this;
}
/**
* The HQL query string to execute. This should only be set if
* {@link #queryProvider(HibernateQueryProvider)} and {@link #queryName(String)} have
* not been set.
*
* @param queryString the HQL query
* @return this instance for method chaining
* @see HibernatePagingItemReader#setQueryString(String)
*/
public HibernatePagingItemReaderBuilder queryString(String queryString) {
this.queryString = queryString;
return this;
}
/**
* The Hibernate {@link SessionFactory} to execute the query against.
*
* @param sessionFactory the session factory
* @return this instance for method chaining
* @see HibernatePagingItemReader#setSessionFactory(SessionFactory)
*/
public HibernatePagingItemReaderBuilder sessionFactory(SessionFactory sessionFactory) {
this.sessionFactory = sessionFactory;
return this;
}
/**
* Indicator for whether to use a {@link org.hibernate.StatelessSession}
* (true) or a {@link org.hibernate.Session} (false).
*
* @param useStatelessSession Defaults to false
* @return this instance for method chaining
* @see HibernatePagingItemReader#setUseStatelessSession(boolean)
* @deprecated This method is deprecated in favor of
* {@link HibernatePagingItemReaderBuilder#useStatelessSession} and will be
* removed in a future version.
*/
@Deprecated
public HibernatePagingItemReaderBuilder useSatelessSession(boolean useStatelessSession) {
return useStatelessSession(useStatelessSession);
}
/**
* Indicator for whether to use a {@link org.hibernate.StatelessSession}
* (true) or a {@link org.hibernate.Session} (false).
*
* @param useStatelessSession Defaults to false
* @return this instance for method chaining
* @see HibernatePagingItemReader#setUseStatelessSession(boolean)
*/
public HibernatePagingItemReaderBuilder useStatelessSession(boolean useStatelessSession) {
this.statelessSession = useStatelessSession;
return this;
}
/**
* Returns a fully constructed {@link HibernatePagingItemReader}.
*
* @return a new {@link HibernatePagingItemReader}
*/
public HibernatePagingItemReader build() {
Assert.notNull(this.sessionFactory, "A SessionFactory must be provided");
Assert.state(this.fetchSize >= 0, "fetchSize must not be negative");
if(this.saveState) {
Assert.hasText(this.name,
"A name is required when saveState is set to true");
}
if(this.queryProvider == null) {
Assert.state(StringUtils.hasText(queryString) ^ StringUtils.hasText(queryName),
"queryString or queryName must be set");
}
HibernatePagingItemReader reader = new HibernatePagingItemReader<>();
reader.setSessionFactory(this.sessionFactory);
reader.setSaveState(this.saveState);
reader.setMaxItemCount(this.maxItemCount);
reader.setCurrentItemCount(this.currentItemCount);
reader.setName(this.name);
reader.setFetchSize(this.fetchSize);
reader.setParameterValues(this.parameterValues);
reader.setQueryName(this.queryName);
reader.setQueryProvider(this.queryProvider);
reader.setQueryString(this.queryString);
reader.setPageSize(this.pageSize);
reader.setUseStatelessSession(this.statelessSession);
return reader;
}
}