org.springframework.batch.item.json.builder.JsonFileItemWriterBuilder Maven / Gradle / Ivy
/*
* Copyright 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.json.builder;
import org.springframework.batch.item.file.FlatFileFooterCallback;
import org.springframework.batch.item.file.FlatFileHeaderCallback;
import org.springframework.batch.item.json.JsonFileItemWriter;
import org.springframework.batch.item.json.JsonObjectMarshaller;
import org.springframework.core.io.Resource;
import org.springframework.util.Assert;
/**
* Builder for {@link JsonFileItemWriter}.
*
* @param type of objects to write as Json output.
* @author Mahmoud Ben Hassine
* @since 4.1
*/
public class JsonFileItemWriterBuilder {
private Resource resource;
private JsonObjectMarshaller jsonObjectMarshaller;
private FlatFileHeaderCallback headerCallback;
private FlatFileFooterCallback footerCallback;
private String name;
private String encoding = JsonFileItemWriter.DEFAULT_CHARSET;
private String lineSeparator = JsonFileItemWriter.DEFAULT_LINE_SEPARATOR;
private boolean append = false;
private boolean forceSync = false;
private boolean saveState = true;
private boolean shouldDeleteIfExists = true;
private boolean shouldDeleteIfEmpty = false;
private boolean transactional = JsonFileItemWriter.DEFAULT_TRANSACTIONAL;
/**
* 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 JsonFileItemWriterBuilder 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 JsonFileItemWriterBuilder name(String name) {
this.name = name;
return this;
}
/**
* A flag indicating that changes should be force-synced to disk on flush. Defaults
* to false.
*
* @param forceSync value to set the flag to
* @return The current instance of the builder.
* @see JsonFileItemWriter#setForceSync(boolean)
*/
public JsonFileItemWriterBuilder forceSync(boolean forceSync) {
this.forceSync = forceSync;
return this;
}
/**
* String used to separate lines in output. Defaults to the System property
* line.separator.
*
* @param lineSeparator value to use for a line separator
* @return The current instance of the builder.
* @see JsonFileItemWriter#setLineSeparator(String)
*/
public JsonFileItemWriterBuilder lineSeparator(String lineSeparator) {
this.lineSeparator = lineSeparator;
return this;
}
/**
* Set the {@link JsonObjectMarshaller} to use to marshal objects to json.
*
* @param jsonObjectMarshaller to use
* @return The current instance of the builder.
* @see JsonFileItemWriter#setJsonObjectMarshaller(JsonObjectMarshaller)
*/
public JsonFileItemWriterBuilder jsonObjectMarshaller(JsonObjectMarshaller jsonObjectMarshaller) {
this.jsonObjectMarshaller = jsonObjectMarshaller;
return this;
}
/**
* The {@link Resource} to be used as output.
*
* @param resource the output of the writer.
* @return The current instance of the builder.
* @see JsonFileItemWriter#setResource(Resource)
*/
public JsonFileItemWriterBuilder resource(Resource resource) {
this.resource = resource;
return this;
}
/**
* Encoding used for output.
*
* @param encoding encoding type.
* @return The current instance of the builder.
* @see JsonFileItemWriter#setEncoding(String)
*/
public JsonFileItemWriterBuilder encoding(String encoding) {
this.encoding = encoding;
return this;
}
/**
* If set to true, once the step is complete, if the resource previously provided is
* empty, it will be deleted.
*
* @param shouldDelete defaults to false
* @return The current instance of the builder
* @see JsonFileItemWriter#setShouldDeleteIfEmpty(boolean)
*/
public JsonFileItemWriterBuilder shouldDeleteIfEmpty(boolean shouldDelete) {
this.shouldDeleteIfEmpty = shouldDelete;
return this;
}
/**
* If set to true, upon the start of the step, if the resource already exists, it will
* be deleted and recreated.
*
* @param shouldDelete defaults to true
* @return The current instance of the builder
* @see JsonFileItemWriter#setShouldDeleteIfExists(boolean)
*/
public JsonFileItemWriterBuilder shouldDeleteIfExists(boolean shouldDelete) {
this.shouldDeleteIfExists = shouldDelete;
return this;
}
/**
* If set to true and the file exists, the output will be appended to the existing
* file.
*
* @param append defaults to false
* @return The current instance of the builder
* @see JsonFileItemWriter#setAppendAllowed(boolean)
*/
public JsonFileItemWriterBuilder append(boolean append) {
this.append = append;
return this;
}
/**
* A callback for header processing.
*
* @param callback {@link FlatFileHeaderCallback} implementation
* @return The current instance of the builder
* @see JsonFileItemWriter#setHeaderCallback(FlatFileHeaderCallback)
*/
public JsonFileItemWriterBuilder headerCallback(FlatFileHeaderCallback callback) {
this.headerCallback = callback;
return this;
}
/**
* A callback for footer processing.
*
* @param callback {@link FlatFileFooterCallback} implementation
* @return The current instance of the builder
* @see JsonFileItemWriter#setFooterCallback(FlatFileFooterCallback)
*/
public JsonFileItemWriterBuilder footerCallback(FlatFileFooterCallback callback) {
this.footerCallback = callback;
return this;
}
/**
* If set to true, the flushing of the buffer is delayed while a transaction is active.
*
* @param transactional defaults to true
* @return The current instance of the builder
* @see JsonFileItemWriter#setTransactional(boolean)
*/
public JsonFileItemWriterBuilder transactional(boolean transactional) {
this.transactional = transactional;
return this;
}
/**
* Validate the configuration and build a new {@link JsonFileItemWriter}.
*
* @return a new instance of the {@link JsonFileItemWriter}
*/
public JsonFileItemWriter build() {
Assert.notNull(this.resource, "A resource is required.");
Assert.notNull(this.jsonObjectMarshaller, "A json object marshaller is required.");
if (this.saveState) {
Assert.hasText(this.name, "A name is required when saveState is true");
}
JsonFileItemWriter jsonFileItemWriter = new JsonFileItemWriter<>(this.resource, this.jsonObjectMarshaller);
jsonFileItemWriter.setName(this.name);
jsonFileItemWriter.setAppendAllowed(this.append);
jsonFileItemWriter.setEncoding(this.encoding);
if (this.headerCallback != null) {
jsonFileItemWriter.setHeaderCallback(this.headerCallback);
}
if (this.footerCallback != null) {
jsonFileItemWriter.setFooterCallback(this.footerCallback);
}
jsonFileItemWriter.setForceSync(this.forceSync);
jsonFileItemWriter.setLineSeparator(this.lineSeparator);
jsonFileItemWriter.setSaveState(this.saveState);
jsonFileItemWriter.setShouldDeleteIfEmpty(this.shouldDeleteIfEmpty);
jsonFileItemWriter.setShouldDeleteIfExists(this.shouldDeleteIfExists);
jsonFileItemWriter.setTransactional(this.transactional);
return jsonFileItemWriter;
}
}