JsonFileItemWriter (Spring Batch 4.1.4.RELEASE API)

java.lang.Object
- org.springframework.batch.item.ItemStreamSupport
- - org.springframework.batch.item.support.AbstractItemStreamItemWriter<T>
  - - org.springframework.batch.item.support.AbstractFileItemWriter<T>
    - - org.springframework.batch.item.json.JsonFileItemWriter<T>

Type Parameters:
T - type of object to write as json representation
All Implemented Interfaces:
ResourceAwareItemWriterItemStream<T>, ItemStream, ItemStreamWriter<T>, ItemWriter<T>, org.springframework.beans.factory.InitializingBean
```
public class JsonFileItemWriter<T>
extends AbstractFileItemWriter<T>
```
Item writer that writes data in json format to an output file. The location of the output file is defined by a Resource and must represent a writable file. Items are transformed to json format using a JsonObjectMarshaller. Items will be enclosed in a json array as follows:
[ {json object}, {json object}, {json object} ]
The implementation is not thread-safe.
Since:
4.1
Author:
Mahmoud Ben Hassine
See Also:
GsonJsonObjectMarshaller, JacksonJsonObjectMarshaller

Nested Class Summary
- Nested classes/interfaces inherited from class org.springframework.batch.item.support.AbstractFileItemWriter
  AbstractFileItemWriter.OutputState

Field Summary
- Fields inherited from class org.springframework.batch.item.support.AbstractFileItemWriter
  append, DEFAULT_CHARSET, DEFAULT_LINE_SEPARATOR, DEFAULT_TRANSACTIONAL, lineSeparator, logger, shouldDeleteIfExists, state

Constructor Summary
Constructors
Constructor Description
JsonFileItemWriter(org.springframework.core.io.Resource resource, JsonObjectMarshaller<T> jsonObjectMarshaller)
Create a new JsonFileItemWriter instance.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`afterPropertiesSet()`	Assert that mandatory properties (jsonObjectMarshaller) are set.
`java.lang.String`	`doWrite(java.util.List<? extends T> items)`	Write out a string of items followed by a "new line", where the format of the new line separator is determined by the underlying operating system.
`void`	`setJsonObjectMarshaller(JsonObjectMarshaller<T> jsonObjectMarshaller)`	Set the `JsonObjectMarshaller` to use to marshal object to json.

Methods inherited from class org.springframework.batch.item.support.AbstractFileItemWriter
close, getOutputState, open, setAppendAllowed, setEncoding, setFooterCallback, setForceSync, setHeaderCallback, setLineSeparator, setResource, setSaveState, setShouldDeleteIfEmpty, setShouldDeleteIfExists, setTransactional, update, write

Methods inherited from class org.springframework.batch.item.ItemStreamSupport
getExecutionContextKey, setExecutionContextName, setName

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - JsonFileItemWriter
```
public JsonFileItemWriter(org.springframework.core.io.Resource resource,
                          JsonObjectMarshaller<T> jsonObjectMarshaller)
```
    Create a new JsonFileItemWriter instance.
    Parameters:
    resource - to write json data to
    jsonObjectMarshaller - used to marshal object into json representation
- Method Detail
  - afterPropertiesSet
```
public void afterPropertiesSet()
                        throws java.lang.Exception
```
    Assert that mandatory properties (jsonObjectMarshaller) are set.
    Throws:
    java.lang.Exception
    See Also:
    InitializingBean.afterPropertiesSet()
  - setJsonObjectMarshaller
```
public void setJsonObjectMarshaller(JsonObjectMarshaller<T> jsonObjectMarshaller)
```
    Set the JsonObjectMarshaller to use to marshal object to json.
    Parameters:
    jsonObjectMarshaller - the marshaller to use
  - doWrite
```
public java.lang.String doWrite(java.util.List<? extends T> items)
```
    Description copied from class: AbstractFileItemWriter
    Write out a string of items followed by a "new line", where the format of the new line separator is determined by the underlying operating system.
    Specified by:
    doWrite in class AbstractFileItemWriter<T>
    Parameters:
    items - to be written
    Returns:
    written lines