/*
* Copyright 2017 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.batch.item.xml.builder;
import java.util.Map;
import org.springframework.batch.item.xml.StaxEventItemWriter;
import org.springframework.batch.item.xml.StaxWriterCallback;
import org.springframework.core.io.Resource;
import org.springframework.oxm.Marshaller;
import org.springframework.util.Assert;
/**
* A builder for the {@link StaxEventItemWriter}.
*
* @author Michael Minella
* @since 4.0
* @see StaxEventItemWriter
*/
public class StaxEventItemWriterBuilder<T> {
private Resource resource;
private Marshaller marshaller;
private StaxWriterCallback headerCallback;
private StaxWriterCallback footerCallback;
private boolean transactional = true;
private boolean forceSync = false;
private boolean shouldDeleteIfEmpty = false;
private String encoding = StaxEventItemWriter.DEFAULT_ENCODING;
private String version = StaxEventItemWriter.DEFAULT_XML_VERSION;
private String rootTagName = StaxEventItemWriter.DEFAULT_ROOT_TAG_NAME;
private Map<String, String> rootElementAttributes;
private boolean overwriteOutput = true;
private boolean saveState = true;
private String name;
/**
* The name used to calculate the key within the
* {@link org.springframework.batch.item.ExecutionContext}. Required if
* {@link StaxEventItemWriterBuilder#saveState(boolean)} is set to true.
*
* @param name name of the reader instance
* @return The current instance of the builder.
* @see StaxEventItemWriter#setName(String)
*/
public StaxEventItemWriterBuilder<T> name(String name) {
this.name = name;
return this;
}
/**
* The {@link Resource} to be used as output.
*
* @param resource the output from the writer
* @return the current instance of the builder.
* @see StaxEventItemWriter#setResource(Resource)
*/
public StaxEventItemWriterBuilder<T> resource(Resource resource) {
this.resource = resource;
return this;
}
/**
* The {@link Marshaller} implementation responsible for the serialization of the
* items to XML. This field is required.
*
* @param marshaller the component used to generate XML
* @return the current instance of the builder.
* @see StaxEventItemWriter#setMarshaller(Marshaller)
*/
public StaxEventItemWriterBuilder<T> marshaller(Marshaller marshaller) {
this.marshaller = marshaller;
return this;
}
/**
* A {@link StaxWriterCallback} to provide any header elements
*
* @param headerCallback a {@link StaxWriterCallback}
* @return the current instance of the builder.
* @see StaxEventItemWriter#setHeaderCallback(StaxWriterCallback)
*/
public StaxEventItemWriterBuilder<T> headerCallback(StaxWriterCallback headerCallback) {
this.headerCallback = headerCallback;
return this;
}
/**
* A {@link StaxWriterCallback} to provide any footer elements
*
* @param footerCallback a {@link StaxWriterCallback}
* @return the current instance of the builder.
* @see StaxEventItemWriter#setFooterCallback(StaxWriterCallback)
*/
public StaxEventItemWriterBuilder<T> footerCallback(StaxWriterCallback footerCallback) {
this.footerCallback = footerCallback;
return this;
}
/**
* The resulting writer is participating in a transaction and writes should be delayed
* as late as possible.
*
* @param transactional indicates that the writer is transactional. Defaults to false.
* @return the current instance of the builder
* @see StaxEventItemWriter#setTransactional(boolean)
*/
public StaxEventItemWriterBuilder<T> transactional(boolean transactional) {
this.transactional = transactional;
return this;
}
/**
* Flag to indicate that changes should be force-synced to disk on flush.
*
* @param forceSync indicates if force sync should occur. Defaults to false.
* @return the current instance of the builder
* @see StaxEventItemWriter#setForceSync(boolean)
*/
public StaxEventItemWriterBuilder<T> forceSync(boolean forceSync) {
this.forceSync = forceSync;
return this;
}
/**
* Flag to indicate that the output file should be deleted if no results were written
* to it. Defaults to false.
*
* @param shouldDelete indicator
* @return the current instance of the builder
* @see StaxEventItemWriter#setShouldDeleteIfEmpty(boolean)
*/
public StaxEventItemWriterBuilder<T> shouldDeleteIfEmpty(boolean shouldDelete) {
this.shouldDeleteIfEmpty = shouldDelete;
return this;
}
/**
* Encoding for the file. Defaults to UTF-8.
*
* @param encoding String encoding algorithm
* @return the current instance of the builder
* @see StaxEventItemWriter#setEncoding(String)
*/
public StaxEventItemWriterBuilder<T> encoding(String encoding) {
this.encoding = encoding;
return this;
}
/**
* Version of XML to be generated. Must be supported by the {@link Marshaller}
* provided.
*
* @param version XML version
* @return the current instance of the builder
* @see StaxEventItemWriter#version
*/
public StaxEventItemWriterBuilder<T> version(String version) {
this.version = version;
return this;
}
/**
* The name of the root tag for the output document.
*
* @param rootTagName tag name
* @return the current instance of the builder
* @see StaxEventItemWriter#setRootTagName(String)
*/
public StaxEventItemWriterBuilder<T> rootTagName(String rootTagName) {
this.rootTagName = rootTagName;
return this;
}
/**
* A Map of attributes to be included in the document's root element.
*
* @param rootElementAttributes map fo attributes
* @return the current instance of the builder.
* @see StaxEventItemWriter#setRootElementAttributes(Map)
*/
public StaxEventItemWriterBuilder<T> rootElementAttributes(Map<String, String> rootElementAttributes) {
this.rootElementAttributes = rootElementAttributes;
return this;
}
/**
* Indicates if an existing file should be overwritten if found. Defaults to true.
*
* @param overwriteOutput indicator
* @return the current instance of the builder.
* @see StaxEventItemWriter#setOverwriteOutput(boolean)
*/
public StaxEventItemWriterBuilder<T> overwriteOutput(boolean overwriteOutput) {
this.overwriteOutput = overwriteOutput;
return this;
}
/**
* Indicates if the state of the writer should be saved in the
* {@link org.springframework.batch.item.ExecutionContext}. Setting this to false
* will impact restartability. Defaults to true.
*
* @param saveState indicator
* @return the current instance of the builder
* @see StaxEventItemWriter#setSaveState(boolean)
*/
public StaxEventItemWriterBuilder<T> saveState(boolean saveState) {
this.saveState = saveState;
return this;
}
/**
* Returns a configured {@link StaxEventItemWriter}
*
* @return a StaxEventItemWriter
*/
public StaxEventItemWriter<T> build() {
Assert.notNull(this.marshaller, "A marshaller is required");
if(this.saveState) {
Assert.notNull(this.name, "A name is required");
}
StaxEventItemWriter<T> writer = new StaxEventItemWriter<>();
writer.setEncoding(this.encoding);
writer.setFooterCallback(this.footerCallback);
writer.setForceSync(this.forceSync);
writer.setHeaderCallback(this.headerCallback);
writer.setMarshaller(this.marshaller);
writer.setOverwriteOutput(this.overwriteOutput);
writer.setResource(this.resource);
writer.setRootElementAttributes(this.rootElementAttributes);
writer.setRootTagName(this.rootTagName);
writer.setSaveState(this.saveState);
writer.setShouldDeleteIfEmpty(this.shouldDeleteIfEmpty);
writer.setTransactional(this.transactional);
writer.setVersion(this.version);
writer.setName(this.name);
return writer;
}
}