/*
* 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.thrift;
import java.io.ByteArrayInputStream;
import java.io.UnsupportedEncodingException;
import org.apache.thrift.protocol.TBinaryProtocol;
import org.apache.thrift.protocol.TField;
import org.apache.thrift.protocol.TProtocol;
import org.apache.thrift.protocol.TProtocolFactory;
import org.apache.thrift.protocol.TProtocolUtil;
import org.apache.thrift.protocol.TType;
import org.apache.thrift.transport.TIOStreamTransport;
import org.apache.thrift.TFieldIdEnum;
/**
* Generic utility for easily deserializing objects from a byte array or Java
* String.
*
*/
public class TDeserializer {
private final TProtocolFactory protocolFactory_;
/**
* Create a new TDeserializer that uses the TBinaryProtocol by default.
*/
public TDeserializer() {
this(new TBinaryProtocol.Factory());
}
/**
* Create a new TDeserializer. It will use the TProtocol specified by the
* factory that is passed in.
*
* @param protocolFactory Factory to create a protocol
*/
public TDeserializer(TProtocolFactory protocolFactory) {
protocolFactory_ = protocolFactory;
}
/**
* Deserialize the Thrift object from a byte array.
*
* @param base The object to read into
* @param bytes The array to read from
*/
public void deserialize(TBase base, byte[] bytes) throws TException {
base.read(
protocolFactory_.getProtocol(
new TIOStreamTransport(
new ByteArrayInputStream(bytes))));
}
/**
* Deserialize the Thrift object from a Java string, using a specified
* character set for decoding.
*
* @param base The object to read into
* @param data The string to read from
* @param charset Valid JVM charset
*/
public void deserialize(TBase base, String data, String charset) throws TException {
try {
deserialize(base, data.getBytes(charset));
} catch (UnsupportedEncodingException uex) {
throw new TException("JVM DOES NOT SUPPORT ENCODING: " + charset);
}
}
/**
* Deserialize only a single Thrift object (addressed by recursively using field id)
* from a byte record.
* @param record The object to read from
* @param tb The object to read into
* @param fieldIdPath The FieldId's that define a path tb
* @throws TException
*/
public void partialDeserialize(TBase tb, byte[] bytes, TFieldIdEnum ... fieldIdPath) throws TException {
// if there are no elements in the path, then the user is looking for the
// regular deserialize method
// TODO: it might be nice not to have to do this check every time to save
// some performance.
if (fieldIdPath.length == 0) {
deserialize(tb, bytes);
return;
}
TProtocol iprot = protocolFactory_.getProtocol(
new TIOStreamTransport(
new ByteArrayInputStream(bytes)));
// index into field ID path being currently searched for
int curPathIndex = 0;
iprot.readStructBegin();
while (curPathIndex < fieldIdPath.length) {
TField field = iprot.readFieldBegin();
// we can stop searching if we either see a stop or we go past the field
// id we're looking for (since fields should now be serialized in asc
// order).
if (field.type == TType.STOP || field.id > fieldIdPath[curPathIndex].getThriftFieldId()) {
return;
}
if (field.id != fieldIdPath[curPathIndex].getThriftFieldId()) {
// Not the field we're looking for. Skip field.
TProtocolUtil.skip(iprot, field.type);
iprot.readFieldEnd();
} else {
// This field is the next step in the path. Step into field.
curPathIndex++;
if (curPathIndex < fieldIdPath.length) {
iprot.readStructBegin();
}
}
}
// when this line is reached, iprot will be positioned at the start of tb.
tb.read(iprot);
}
/**
* Deserialize the Thrift object from a Java string, using the default JVM
* charset encoding.
*
* @param base The object to read into
* @param data The string to read from
*/
public void toString(TBase base, String data) throws TException {
deserialize(base, data.getBytes());
}
}