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/* * 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 * * 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.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; } }