StreamJsonSerializer.java
/*
** Module : StreamJsonSerializer.java
** Abstract : Json stream serialization.
**
** Copyright (c) 2019-2023, Golden Code Development Corporation.
**
** -#- -I- --Date-- ----------------------------------------Description---------------------------------------
** 001 HC 20190707 Initial version.
** OM 20190709 The backing stream can now be flushed and closed. Fixed decimal formatting.
** 002 CA 20190724 Fixed rawDecimalValue - it needs to write a value, and not 'raw'.
** CA 20190812 rawDecimalValue - removed the '.0' - not clear why this was added in the first
** place.
** 003 CA 20210709 Force non-scientific format for BigDecimal numbers.
** 004 GBB 20230512 Logging methods replaced by CentralLogger/ConversionStatus.
*/
/*
** This program is free software: you can redistribute it and/or modify
** it under the terms of the GNU Affero General Public License as
** published by the Free Software Foundation, either version 3 of the
** License, or (at your option) any later version.
**
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
** GNU Affero General Public License for more details.
**
** You may find a copy of the GNU Affero GPL version 3 at the following
** location: https://www.gnu.org/licenses/agpl-3.0.en.html
**
** Additional terms under GNU Affero GPL version 3 section 7:
**
** Under Section 7 of the GNU Affero GPL version 3, the following additional
** terms apply to the works covered under the License. These additional terms
** are non-permissive additional terms allowed under Section 7 of the GNU
** Affero GPL version 3 and may not be removed by you.
**
** 0. Attribution Requirement.
**
** You must preserve all legal notices or author attributions in the covered
** work or Appropriate Legal Notices displayed by works containing the covered
** work. You may not remove from the covered work any author or developer
** credit already included within the covered work.
**
** 1. No License To Use Trademarks.
**
** This license does not grant any license or rights to use the trademarks
** Golden Code, FWD, any Golden Code or FWD logo, or any other trademarks
** of Golden Code Development Corporation. You are not authorized to use the
** name Golden Code, FWD, or the names of any author or contributor, for
** publicity purposes without written authorization.
**
** 2. No Misrepresentation of Affiliation.
**
** You may not represent yourself as Golden Code Development Corporation or FWD.
**
** You may not represent yourself for publicity purposes as associated with
** Golden Code Development Corporation, FWD, or any author or contributor to
** the covered work, without written authorization.
**
** 3. No Misrepresentation of Source or Origin.
**
** You may not represent the covered work as solely your work. All modified
** versions of the covered work must be marked in a reasonable way to make it
** clear that the modified work is not originating from Golden Code Development
** Corporation or FWD. All modified versions must contain the notices of
** attribution required in this license.
*/
package com.goldencode.p2j.persist.serial;
import com.fasterxml.jackson.core.*;
import com.fasterxml.jackson.core.JsonGenerator.Feature;
import com.fasterxml.jackson.core.util.*;
import com.fasterxml.jackson.databind.*;
import com.goldencode.p2j.util.logging.*;
import java.io.*;
import java.math.*;
/**
* Serializes json structure to a stream.
*/
public class StreamJsonSerializer
implements JsonStructureCallback
{
/** Logger */
private static final CentralLogger LOG = CentralLogger.get(StreamJsonSerializer.class);
/** Jackson json generator */
private JsonGenerator gen;
/**
* Constructor.
*
* @param out
* Output stream.
* @param encoding
* Character encoding.
* @param pretty
* Pretty print flag.
*
* @throws IOException
* when IO error occurs.
*/
public StreamJsonSerializer(OutputStream out, JsonEncoding encoding, boolean pretty)
throws IOException
{
ObjectMapper mapper = new ObjectMapper();
mapper.configure(Feature.WRITE_BIGDECIMAL_AS_PLAIN, true);
JsonFactory factory = mapper.getFactory();
gen = factory.createGenerator(out, encoding);
if (pretty)
{
// The way 4GL formats JSON is really strange. This small change makes it a bit easy to
// spot changes allowing at least records on consecutive lines to be identically as 4GL
gen.setPrettyPrinter(new DefaultPrettyPrinter()
{
/**
* Method called after an object field has been output, but before the value is
* output.
*/
public void writeObjectFieldValueSeparator(JsonGenerator jg)
throws IOException
{
jg.writeRaw(": ");
}
});
}
else
{
gen.setPrettyPrinter(new MinimalPrettyPrinter());
}
}
/**
* Close the stream. Closes the internal stream.
*
* @throws IOException
* when IO error occurs.
*/
public void closeStream()
throws IOException
{
gen.close();
}
/**
* Called when json object start is encountered.
*/
@Override
public void startObject()
{
try
{
gen.writeStartObject();
}
catch (IOException e)
{
LOG.info("", e);
}
}
/**
* Called when json object end is encountered.
*/
@Override
public void endObject()
{
try
{
gen.writeEndObject();
}
catch (IOException e)
{
LOG.info("", e);
}
}
/**
* Called when json array start is encountered.
*/
@Override
public void startArray()
{
try
{
gen.writeStartArray();
}
catch (IOException e)
{
LOG.info("", e);
}
}
/**
* Called when json array end is encountered.
*/
@Override
public void endArray()
{
try
{
gen.writeEndArray();
}
catch (IOException e)
{
LOG.info("", e);
}
}
/**
* Called when json field is encountered.
*
* @param name
* Field name.
*/
@Override
public void fieldName(String name)
{
try
{
gen.writeFieldName(name);
}
catch (IOException e)
{
LOG.info("", e);
}
}
/**
* Called when json boolean value is encountered.
*
* @param value
* The value.
*/
@Override
public void booleanValue(boolean value)
{
try
{
gen.writeBoolean(value);
}
catch (IOException e)
{
LOG.info("", e);
}
}
/**
* Called when json string value is encountered.
*
* @param value
* The value.
*/
@Override
public void stringValue(String value)
{
try
{
gen.writeString(value);
}
catch (IOException e)
{
LOG.info("", e);
}
}
/**
* Called when json number value is encountered.
*
* @param value
* The value.
*/
@Override
public void numberValue(Number value)
{
try
{
if (value == null)
{
gen.writeNull();
}
else if (value instanceof Short)
{
gen.writeNumber((Short) value);
}
else if (value instanceof Integer)
{
gen.writeNumber((Integer) value);
}
else if (value instanceof Long)
{
gen.writeNumber((Long) value);
}
else if (value instanceof Double)
{
gen.writeNumber((Double) value);
}
else if (value instanceof Float)
{
gen.writeNumber((Float) value);
}
else if (value instanceof BigInteger)
{
gen.writeNumber((BigInteger) value);
}
else if (value instanceof BigDecimal)
{
gen.writeNumber((BigDecimal) value);
}
else
{
throw new RuntimeException("Unsupported number type " + value.getClass());
}
}
catch (IOException e)
{
LOG.info("", e);
}
}
/**
* Called when json null value is encountered.
*/
@Override
public void nullValue()
{
try
{
gen.writeNull();
}
catch (IOException e)
{
LOG.severe("", e);
}
}
/**
* Called when json raw decimal value is encountered.
*
* @param value
* The value.
*/
@Override
public void rawDecimalValue(String value)
{
try
{
if (value.indexOf('.') == -1)
{
// CA: why is this here? what specific case does this solve?
// OM: the decimal numbers serialize by ABL always have the decimal point '.' (Ex: "42.0").
// the [BigDecimal] that we use will drop it if the decimals are null (Ex: "42").
value += ".0";
}
gen.writeRawValue(value);
}
catch (IOException e)
{
LOG.info("", e);
}
}
}