org.apache.axis2.json.AbstractJSONDataSource Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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
*
* http://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.apache.axis2.json;
import org.apache.axiom.om.OMDataSource;
import org.apache.axiom.om.OMException;
import org.apache.axiom.om.OMOutputFormat;
import javax.xml.stream.XMLStreamConstants;
import javax.xml.stream.XMLStreamReader;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamWriter;
import java.io.IOException;
import java.io.OutputStream;
import java.io.Reader;
import java.io.Writer;
import java.io.BufferedReader;
/**
* JSONDataSource keeps the JSON String inside and consumes it when needed. This is to be kept in
* the OMSourcedElement and can be used either to expand the tree or get the JSON String
* directly without expanding. This uses the "Mapped" JSON convention.
*/
public abstract class AbstractJSONDataSource implements OMDataSource {
private Reader jsonReader;
private String jsonString;
private boolean isRead = false;
protected String localName;
public AbstractJSONDataSource(Reader jsonReader, String localName) {
this.jsonReader = jsonReader;
this.localName = localName;
}
/**
* Writes JSON into the output stream. As this should write JSON, it directly gets the JSON
* string and writes it without expanding the tree.
*
* @param outputStream the stream to be written into
* @param omOutputFormat format of the message, this is ignored.
* @throws javax.xml.stream.XMLStreamException
* if there is an error while writing the message in to the output stream.
*/
public void serialize(OutputStream outputStream, OMOutputFormat omOutputFormat)
throws XMLStreamException {
try {
outputStream.write(getCompleteJOSNString().getBytes());
} catch (IOException e) {
throw new OMException();
}
}
/**
* Writes JSON through the writer. As this should write JSON, it directly gets the JSON string
* and writes it without expanding the tree.
*
* @param writer Writer to be written into
* @param omOutputFormat format of the message, this is ignored.
* @throws javax.xml.stream.XMLStreamException
* if there is an error while writing the message through the writer.
*/
public void serialize(Writer writer, OMOutputFormat omOutputFormat)
throws XMLStreamException {
try {
writer.write(getCompleteJOSNString());
} catch (IOException e) {
throw new OMException();
}
}
/**
* Writes XML through the XMLStreamWriter. As the input data source is JSON, this method needs
* to get a StAX reader from that JSON String. Therefore this uses the getReader() method to get
* the StAX reader writes the events into the XMLStreamWriter.
*
* @param xmlStreamWriter StAX writer to be written into
* @throws javax.xml.stream.XMLStreamException
* if there is an error while writing the message through the StAX writer.
*/
public void serialize(XMLStreamWriter xmlStreamWriter) throws XMLStreamException {
XMLStreamReader reader = getReader();
xmlStreamWriter.writeStartDocument();
while (reader.hasNext()) {
int x = reader.next();
switch (x) {
case XMLStreamConstants.START_ELEMENT:
xmlStreamWriter.writeStartElement(reader.getPrefix(), reader.getLocalName(),
reader.getNamespaceURI());
int namespaceCount = reader.getNamespaceCount();
for (int i = namespaceCount - 1; i >= 0; i--) {
xmlStreamWriter.writeNamespace(reader.getNamespacePrefix(i),
reader.getNamespaceURI(i));
}
int attributeCount = reader.getAttributeCount();
for (int i = 0; i < attributeCount; i++) {
xmlStreamWriter.writeAttribute(reader.getAttributePrefix(i),
reader.getAttributeNamespace(i),
reader.getAttributeLocalName(i),
reader.getAttributeValue(i));
}
break;
case XMLStreamConstants.START_DOCUMENT:
break;
case XMLStreamConstants.CHARACTERS:
xmlStreamWriter.writeCharacters(reader.getText());
break;
case XMLStreamConstants.CDATA:
xmlStreamWriter.writeCData(reader.getText());
break;
case XMLStreamConstants.END_ELEMENT:
xmlStreamWriter.writeEndElement();
break;
case XMLStreamConstants.END_DOCUMENT:
xmlStreamWriter.writeEndDocument();
break;
case XMLStreamConstants.SPACE:
break;
case XMLStreamConstants.COMMENT:
xmlStreamWriter.writeComment(reader.getText());
break;
case XMLStreamConstants.DTD:
xmlStreamWriter.writeDTD(reader.getText());
break;
case XMLStreamConstants.PROCESSING_INSTRUCTION:
xmlStreamWriter
.writeProcessingInstruction(reader.getPITarget(), reader.getPIData());
break;
case XMLStreamConstants.ENTITY_REFERENCE:
xmlStreamWriter.writeEntityRef(reader.getLocalName());
break;
default :
throw new OMException();
}
}
xmlStreamWriter.writeEndDocument();
}
/**
* Gives the StAX reader using the "Mapped" formatted input JSON String.
*
* @return The XMLStreamReader according to the JSON String.
* @throws javax.xml.stream.XMLStreamException
* if there is an error while making the StAX reader.
*/
public abstract XMLStreamReader getReader() throws XMLStreamException;
//returns the json string by consuming the JSON input stream.
protected String getJSONString() {
if (isRead) {
return jsonString;
} else {
try {
BufferedReader br = new BufferedReader(jsonReader);
StringBuilder sb = new StringBuilder(512);
char[] tempBuf = new char[512];
int readLen;
while((readLen = br.read(tempBuf)) != -1) {
sb.append(tempBuf, 0, readLen);
}
jsonString = sb.toString();
} catch (IOException e) {
throw new OMException();
}
isRead = true;
return jsonString;
}
}
public String getCompleteJOSNString() {
return "{" + localName + ":" + getJSONString();
}
}