/*******************************************************************************
* Copyright (c) 2014, 2015 Oracle and/or its affiliates. All rights reserved.
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
* which accompanies this distribution.
* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
* and the Eclipse Distribution License is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* Contributors:
* Iaroslav Savytskyi - 2.6 - initial implementation
******************************************************************************/
package org.eclipse.persistence.internal.oxm.record.json;
import org.eclipse.persistence.exceptions.XMLMarshalException;
import org.eclipse.persistence.internal.oxm.Constants;
import org.eclipse.persistence.internal.oxm.ConversionManager;
import org.eclipse.persistence.internal.oxm.MediaType;
import org.eclipse.persistence.internal.oxm.Unmarshaller;
import org.eclipse.persistence.internal.oxm.mappings.Field;
import org.eclipse.persistence.internal.oxm.record.AbstractUnmarshalRecord;
import org.eclipse.persistence.internal.oxm.record.ExtendedContentHandler;
import org.eclipse.persistence.internal.oxm.record.XMLReaderAdapter;
import org.eclipse.persistence.oxm.mappings.nullpolicy.AbstractNullPolicy;
import org.xml.sax.ContentHandler;
import org.xml.sax.ErrorHandler;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import javax.json.Json;
import javax.json.JsonArrayBuilder;
import javax.json.JsonException;
import javax.json.JsonObjectBuilder;
import javax.json.JsonStructure;
import javax.json.JsonValue;
import javax.json.stream.JsonParser;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.math.BigDecimal;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayDeque;
import java.util.Deque;
/**
* Reader for JSR-353 stream (StAX) parser.
* <p/>
* Could be instantiated with {@link JsonParserReader.JsonParserReaderBuilder#build()};
*/
public final class JsonParserReader extends XMLReaderAdapter {
private final JsonParser parser;
private final JsonStructureReader structureReader;
/**
* Parsing stack
*/
private final Deque<JsonStructureBuilder> stack = new ArrayDeque<>();
/**
* Private constructor
* Use {@link JsonParserReader.JsonParserReaderBuilder} to instantiate the class;
*/
private JsonParserReader(JsonParserReaderBuilder b) {
this.parser = b.parser;
if (b.resultClass == null)
this.structureReader = new JsonStructureReader(b.um);
else
this.structureReader = new JsonStructureReader(b.um, b.resultClass);
}
@Override
public void parse(InputSource input) throws IOException, SAXException {
if (null == input) {
doParsing(parser);
return;
}
if (null != input.getCharacterStream()) {
doParsing(Json.createParser(input.getCharacterStream()));
return;
}
InputStream inputStream = null;
try {
if (null != (inputStream = input.getByteStream())) {
doParsing(Json.createParser(inputStream));
return;
}
try {
URL url = new URL(input.getSystemId());
inputStream = url.openStream();
} catch (MalformedURLException malformedURLException) {
try {
inputStream = new FileInputStream(input.getSystemId());
} catch (FileNotFoundException fileNotFoundException) {
throw malformedURLException;
}
}
doParsing(Json.createParser(inputStream));
} catch (JsonException je) {
throw XMLMarshalException.unmarshalException(je);
} finally {
if (null != inputStream) {
inputStream.close();
}
}
}
@Override
public void parse(String systemId) {
try {
parse(new InputSource(systemId));
} catch (IOException | SAXException e) {
throw XMLMarshalException.unmarshalException(e);
}
}
private void doParsing(JsonParser parser) throws SAXException, IOException {
JsonStructureBuilder builder = null;
while (parser.hasNext()) {
builder = parseEvent(parser);
}
assert builder != null;
JsonStructure jsonStructure = builder.build();
structureReader.parseRoot(jsonStructure);
}
private JsonStructureBuilder parseEvent(JsonParser jp) throws SAXException {
JsonParser.Event e = jp.next();
JsonStructureBuilder top = stack.peek();
switch (e) {
case START_ARRAY: {
JsonStructureBuilder b = new ArrayBuilder(Json.createArrayBuilder());
stack.push(b);
break;
}
case START_OBJECT: {
JsonStructureBuilder b = new ObjectBuilder(Json.createObjectBuilder());
stack.push(b);
break;
}
case KEY_NAME: {
top.setKey(jp.getString());
break;
}
case VALUE_STRING: {
top.add(jp.getString());
break;
}
case VALUE_NUMBER: {
top.add(jp.getBigDecimal());
break;
}
case VALUE_TRUE: {
top.add(Boolean.TRUE);
break;
}
case VALUE_FALSE: {
top.add(Boolean.FALSE);
break;
}
case VALUE_NULL: {
top.addNull();
break;
}
case END_ARRAY:
case END_OBJECT: { // adding build element to the upper one
JsonStructureBuilder b = stack.pop();
top = stack.peek();
if (top != null)
top.add(b.build());
return b;
}
default:
throw new IllegalStateException("Unhandled event: " + e);
}
return null;
}
// ******************************** Redirecting requests to JsonStructureReader *******************************
public boolean isNullRepresentedByXsiNil(AbstractNullPolicy nullPolicy) {
return true;
}
@Override
public Object convertValueBasedOnSchemaType(Field xmlField, Object value, ConversionManager conversionManager, AbstractUnmarshalRecord record) {
return structureReader.convertValueBasedOnSchemaType(xmlField, value, conversionManager, record);
}
@Override
public char getNamespaceSeparator() {
return structureReader.getNamespaceSeparator();
}
@Override
public ErrorHandler getErrorHandler() {
return structureReader.getErrorHandler();
}
@Override
public ExtendedContentHandler getContentHandler() {
return structureReader.getContentHandler();
}
@Override
public void setContentHandler(ContentHandler contentHandler) {
structureReader.setContentHandler(contentHandler);
}
@Override
public boolean isInCollection() {
return structureReader.isInCollection();
}
@Override
public MediaType getMediaType() {
return Constants.APPLICATION_JSON;
}
@Override
public boolean isNamespaceAware() {
return structureReader.isNamespaceAware();
}
// ************************************************************************************************************
/**
* JsonStructure builder
*/
private static interface JsonStructureBuilder {
JsonStructure build();
void add(JsonValue value);
void add(String value);
void add(BigDecimal value);
void add(boolean value);
void addNull();
void setKey(String key);
}
/**
* Builder for JsonParserReader
*/
public static final class JsonParserReaderBuilder {
private final JsonParser parser;
private Unmarshaller um;
private Class resultClass;
public JsonParserReaderBuilder(JsonParser parser) {
this.parser = parser;
}
public JsonParserReaderBuilder setUnmarshaller(Unmarshaller um) {
this.um = um;
return this;
}
public JsonParserReaderBuilder setResultClass(Class resultClass) {
this.resultClass = resultClass;
return this;
}
public JsonParserReader build() {
if (parser == null)
throw new NullPointerException("JsonParser can't be null");
return new JsonParserReader(this);
}
}
private static final class ObjectBuilder implements JsonStructureBuilder {
private final JsonObjectBuilder b;
private String key;
public ObjectBuilder(JsonObjectBuilder b) {
this.b = b;
}
@Override
public JsonStructure build() {
return b.build();
}
@Override
public void add(JsonValue value) {
b.add(key, value);
}
@Override
public void add(String value) {
b.add(key, value);
}
@Override
public void add(BigDecimal value) {
b.add(key, value);
}
@Override
public void add(boolean value) {
b.add(key, value);
}
@Override
public void addNull() {
b.addNull(key);
}
@Override
public void setKey(String key) {
this.key = key;
}
}
private static final class ArrayBuilder implements JsonStructureBuilder {
private final JsonArrayBuilder b;
public ArrayBuilder(JsonArrayBuilder b) {
this.b = b;
}
@Override
public JsonStructure build() {
return b.build();
}
@Override
public void add(JsonValue value) {
b.add(value);
}
@Override
public void add(String value) {
b.add(value);
}
@Override
public void add(BigDecimal value) {
b.add(value);
}
@Override
public void add(boolean value) {
b.add(value);
}
@Override
public void addNull() {
b.addNull();
}
@Override
public void setKey(String key) {
// noop
}
}
}