/**
* Copyright Microsoft Corporation
*
* 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
* 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 com.microsoft.azure.storage.blob;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Stack;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;
import com.microsoft.azure.storage.Constants;
import com.microsoft.azure.storage.core.SR;
import com.microsoft.azure.storage.core.Utility;
/**
* RESERVED FOR INTERNAL USE. A class used to deserialize a list of blocks.
*/
class BlockListHandler extends DefaultHandler {
private final Stack<String> elementStack = new Stack<String>();
private StringBuilder bld = new StringBuilder();
private final ArrayList<BlockEntry> blocks = new ArrayList<BlockEntry>();
private BlockSearchMode searchMode;
private String blockName;
private Long blockSize;
/**
* Parses a list of {@link BlockEntry} items from the given XML stream.
*
* @throws SAXException
* @throws ParserConfigurationException
* @throws IOException
*/
public static ArrayList<BlockEntry> getBlockList(InputStream streamRef) throws ParserConfigurationException,
SAXException, IOException {
SAXParser saxParser = Utility.getSAXParser();
BlockListHandler handler = new BlockListHandler();
saxParser.parse(streamRef, handler);
return handler.blocks;
}
@Override
public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
this.elementStack.push(localName);
if (BlobConstants.UNCOMMITTED_BLOCKS_ELEMENT.equals(localName)) {
this.searchMode = BlockSearchMode.UNCOMMITTED;
}
else if (BlobConstants.COMMITTED_BLOCKS_ELEMENT.equals(localName)) {
this.searchMode = BlockSearchMode.COMMITTED;
}
}
@Override
public void endElement(String uri, String localName, String qName) throws SAXException {
String currentNode = this.elementStack.pop();
// if the node popped from the stack and the localName don't match, the xml document is improperly formatted
if (!localName.equals(currentNode)) {
throw new SAXException(SR.INVALID_RESPONSE_RECEIVED);
}
String value = this.bld.toString();
if (value.isEmpty()) {
value = null;
}
if (BlobConstants.BLOCK_ELEMENT.equals(currentNode)) {
final BlockEntry newBlock = new BlockEntry(this.blockName, this.searchMode);
newBlock.setSize(this.blockSize);
this.blocks.add(newBlock);
}
else if (Constants.NAME_ELEMENT.equals(currentNode)) {
this.blockName = value;
}
else if (BlobConstants.SIZE_ELEMENT.equals(currentNode)) {
this.blockSize = Long.parseLong(value);
}
this.bld = new StringBuilder();
}
@Override
public void characters(char ch[], int start, int length) throws SAXException {
this.bld.append(ch, start, length);
}
}