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Thrift is a software framework for scalable cross-language services development.
/*
* 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 org.apache.thrift.meta_data.EnumMetaData;
import org.apache.thrift.meta_data.StructMetaData;
import org.apache.thrift.partial.TFieldData;
import org.apache.thrift.partial.ThriftFieldValueProcessor;
import org.apache.thrift.partial.ThriftMetadata;
import org.apache.thrift.partial.ThriftStructProcessor;
import org.apache.thrift.partial.Validate;
import org.apache.thrift.protocol.TBinaryProtocol;
import org.apache.thrift.protocol.TField;
import org.apache.thrift.protocol.TList;
import org.apache.thrift.protocol.TMap;
import org.apache.thrift.protocol.TProtocol;
import org.apache.thrift.protocol.TProtocolFactory;
import org.apache.thrift.protocol.TProtocolUtil;
import org.apache.thrift.protocol.TSet;
import org.apache.thrift.protocol.TType;
import org.apache.thrift.transport.TMemoryInputTransport;
import org.apache.thrift.transport.TTransportException;
import java.io.UnsupportedEncodingException;
import java.nio.ByteBuffer;
import java.util.Collection;
/**
* Generic utility for easily deserializing objects from a byte array or Java
* String.
*
*/
public class TDeserializer {
private final TProtocol protocol_;
private final TMemoryInputTransport trans_;
// Metadata that describes fields to deserialize during partial deserialization.
private ThriftMetadata.ThriftStruct metadata_ = null;
// Processor that handles deserialized field values during partial deserialization.
private ThriftFieldValueProcessor processor_ = null;
/**
* Create a new TDeserializer that uses the TBinaryProtocol by default.
*
* @throws TTransportException if there an error initializing the underlying transport.
*/
public TDeserializer() throws TTransportException {
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
* @throws TTransportException if there an error initializing the underlying transport.
*/
public TDeserializer(TProtocolFactory protocolFactory) throws TTransportException {
trans_ = new TMemoryInputTransport(new TConfiguration());
protocol_ = protocolFactory.getProtocol(trans_);
}
/**
* Construct a new TDeserializer that supports partial deserialization
* that outputs instances of type controlled by the given {@code processor}.
*
* @param thriftClass a TBase derived class.
* @param fieldNames list of fields to deserialize.
* @param processor the Processor that handles deserialized field values.
* @param protocolFactory the Factory to create a protocol.
*/
public TDeserializer(
Class thriftClass,
Collection fieldNames,
ThriftFieldValueProcessor processor,
TProtocolFactory protocolFactory) throws TTransportException {
this(protocolFactory);
Validate.checkNotNull(thriftClass, "thriftClass");
Validate.checkNotNull(fieldNames, "fieldNames");
Validate.checkNotNull(processor, "processor");
metadata_ = ThriftMetadata.ThriftStruct.fromFieldNames(thriftClass, fieldNames);
processor_ = processor;
}
/**
* Construct a new TDeserializer that supports partial deserialization
* that outputs {@code TBase} instances.
*
* @param thriftClass a TBase derived class.
* @param fieldNames list of fields to deserialize.
* @param protocolFactory the Factory to create a protocol.
*/
public TDeserializer(
Class thriftClass,
Collection fieldNames,
TProtocolFactory protocolFactory) throws TTransportException {
this(thriftClass, fieldNames, new ThriftStructProcessor(), protocolFactory);
}
/**
* Gets the metadata used for partial deserialization.
*
* @return the metadata used for partial deserialization.
*/
public ThriftMetadata.ThriftStruct getMetadata() {
return metadata_;
}
/**
* Deserialize the Thrift object from a byte array.
*
* @param base The object to read into
* @param bytes The array to read from
* @throws TException if an error is encountered during deserialization.
*/
public void deserialize(TBase base, byte[] bytes) throws TException {
deserialize(base, bytes, 0, bytes.length);
}
/**
* Deserialize the Thrift object from a byte array.
*
* @param base The object to read into
* @param bytes The array to read from
* @param offset The offset into {@code bytes}
* @param length The length to read from {@code bytes}
* @throws TException if an error is encountered during deserialization.
*/
public void deserialize(TBase base, byte[] bytes, int offset, int length) throws TException {
if (this.isPartialDeserializationMode()) {
this.partialDeserializeThriftObject(base, bytes, offset, length);
} else {
try {
trans_.reset(bytes, offset, length);
base.read(protocol_);
} finally {
trans_.clear();
protocol_.reset();
}
}
}
/**
* 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
* @throws TException if an error is encountered during deserialization.
*/
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);
} finally {
protocol_.reset();
}
}
/**
* Deserialize only a single Thrift object (addressed by recursively using field id)
* from a byte record.
* @param tb The object to read into
* @param bytes The serialized object to read from
* @param fieldIdPathFirst First of the FieldId's that define a path tb
* @param fieldIdPathRest The rest FieldId's that define a path tb
* @throws TException if an error is encountered during deserialization.
*/
public void partialDeserialize(TBase tb, byte[] bytes, TFieldIdEnum fieldIdPathFirst, TFieldIdEnum ... fieldIdPathRest) throws TException {
try {
if (locateField(bytes, fieldIdPathFirst, fieldIdPathRest) != null) {
// if this line is reached, iprot will be positioned at the start of tb.
tb.read(protocol_);
}
} catch (Exception e) {
throw new TException(e);
} finally {
trans_.clear();
protocol_.reset();
}
}
/**
* Deserialize only a boolean field (addressed by recursively using field id)
* from a byte record.
* @param bytes The serialized object to read from
* @param fieldIdPathFirst First of the FieldId's that define a path to a boolean field
* @param fieldIdPathRest The rest FieldId's that define a path to a boolean field
* @return the deserialized value.
* @throws TException if an error is encountered during deserialization.
*/
public Boolean partialDeserializeBool(byte[] bytes, TFieldIdEnum fieldIdPathFirst, TFieldIdEnum ... fieldIdPathRest) throws TException {
return (Boolean) partialDeserializeField(TType.BOOL, bytes, fieldIdPathFirst, fieldIdPathRest);
}
/**
* Deserialize only a byte field (addressed by recursively using field id)
* from a byte record.
* @param bytes The serialized object to read from
* @param fieldIdPathFirst First of the FieldId's that define a path to a byte field
* @param fieldIdPathRest The rest FieldId's that define a path to a byte field
* @return the deserialized value.
* @throws TException if an error is encountered during deserialization.
*/
public Byte partialDeserializeByte(byte[] bytes, TFieldIdEnum fieldIdPathFirst, TFieldIdEnum ... fieldIdPathRest) throws TException {
return (Byte) partialDeserializeField(TType.BYTE, bytes, fieldIdPathFirst, fieldIdPathRest);
}
/**
* Deserialize only a double field (addressed by recursively using field id)
* from a byte record.
* @param bytes The serialized object to read from
* @param fieldIdPathFirst First of the FieldId's that define a path to a double field
* @param fieldIdPathRest The rest FieldId's that define a path to a double field
* @return the deserialized value.
* @throws TException if an error is encountered during deserialization.
*/
public Double partialDeserializeDouble(byte[] bytes, TFieldIdEnum fieldIdPathFirst, TFieldIdEnum ... fieldIdPathRest) throws TException {
return (Double) partialDeserializeField(TType.DOUBLE, bytes, fieldIdPathFirst, fieldIdPathRest);
}
/**
* Deserialize only an i16 field (addressed by recursively using field id)
* from a byte record.
* @param bytes The serialized object to read from
* @param fieldIdPathFirst First of the FieldId's that define a path to an i16 field
* @param fieldIdPathRest The rest FieldId's that define a path to an i16 field
* @return the deserialized value.
* @throws TException if an error is encountered during deserialization.
*/
public Short partialDeserializeI16(byte[] bytes, TFieldIdEnum fieldIdPathFirst, TFieldIdEnum ... fieldIdPathRest) throws TException {
return (Short) partialDeserializeField(TType.I16, bytes, fieldIdPathFirst, fieldIdPathRest);
}
/**
* Deserialize only an i32 field (addressed by recursively using field id)
* from a byte record.
* @param bytes The serialized object to read from
* @param fieldIdPathFirst First of the FieldId's that define a path to an i32 field
* @param fieldIdPathRest The rest FieldId's that define a path to an i32 field
* @return the deserialized value.
* @throws TException if an error is encountered during deserialization.
*/
public Integer partialDeserializeI32(byte[] bytes, TFieldIdEnum fieldIdPathFirst, TFieldIdEnum ... fieldIdPathRest) throws TException {
return (Integer) partialDeserializeField(TType.I32, bytes, fieldIdPathFirst, fieldIdPathRest);
}
/**
* Deserialize only an i64 field (addressed by recursively using field id)
* from a byte record.
* @param bytes The serialized object to read from
* @param fieldIdPathFirst First of the FieldId's that define a path to an i64 field
* @param fieldIdPathRest The rest FieldId's that define a path to an i64 field
* @return the deserialized value.
* @throws TException if an error is encountered during deserialization.
*/
public Long partialDeserializeI64(byte[] bytes, TFieldIdEnum fieldIdPathFirst, TFieldIdEnum ... fieldIdPathRest) throws TException {
return (Long) partialDeserializeField(TType.I64, bytes, fieldIdPathFirst, fieldIdPathRest);
}
/**
* Deserialize only a string field (addressed by recursively using field id)
* from a byte record.
* @param bytes The serialized object to read from
* @param fieldIdPathFirst First of the FieldId's that define a path to a string field
* @param fieldIdPathRest The rest FieldId's that define a path to a string field
* @return the deserialized value.
* @throws TException if an error is encountered during deserialization.
*/
public String partialDeserializeString(byte[] bytes, TFieldIdEnum fieldIdPathFirst, TFieldIdEnum ... fieldIdPathRest) throws TException {
return (String) partialDeserializeField(TType.STRING, bytes, fieldIdPathFirst, fieldIdPathRest);
}
/**
* Deserialize only a binary field (addressed by recursively using field id)
* from a byte record.
* @param bytes The serialized object to read from
* @param fieldIdPathFirst First of the FieldId's that define a path to a binary field
* @param fieldIdPathRest The rest FieldId's that define a path to a binary field
* @return the deserialized value.
* @throws TException if an error is encountered during deserialization.
*/
public ByteBuffer partialDeserializeByteArray(byte[] bytes, TFieldIdEnum fieldIdPathFirst, TFieldIdEnum ... fieldIdPathRest) throws TException {
// TType does not have binary, so we use the arbitrary num 100
return (ByteBuffer) partialDeserializeField((byte)100, bytes, fieldIdPathFirst, fieldIdPathRest);
}
/**
* Deserialize only the id of the field set in a TUnion (addressed by recursively using field id)
* from a byte record.
* @param bytes The serialized object to read from
* @param fieldIdPathFirst First of the FieldId's that define a path to a TUnion
* @param fieldIdPathRest The rest FieldId's that define a path to a TUnion
* @return the deserialized value.
* @throws TException if an error is encountered during deserialization.
*/
public Short partialDeserializeSetFieldIdInUnion(byte[] bytes, TFieldIdEnum fieldIdPathFirst, TFieldIdEnum ... fieldIdPathRest) throws TException {
try {
TField field = locateField(bytes, fieldIdPathFirst, fieldIdPathRest);
if (field != null){
protocol_.readStructBegin(); // The Union
return protocol_.readFieldBegin().id; // The field set in the union
}
return null;
} catch (Exception e) {
throw new TException(e);
} finally {
trans_.clear();
protocol_.reset();
}
}
private Object partialDeserializeField(byte ttype, byte[] bytes, TFieldIdEnum fieldIdPathFirst, TFieldIdEnum ... fieldIdPathRest) throws TException {
try {
TField field = locateField(bytes, fieldIdPathFirst, fieldIdPathRest);
if (field != null) {
if (ttype == field.type) {
// if this point is reached, iprot will be positioned at the start of
// the field
switch (ttype) {
case TType.BOOL:
return protocol_.readBool();
case TType.BYTE:
return protocol_.readByte();
case TType.DOUBLE:
return protocol_.readDouble();
case TType.I16:
return protocol_.readI16();
case TType.I32:
return protocol_.readI32();
case TType.I64:
return protocol_.readI64();
case TType.STRING:
return protocol_.readString();
default:
return null;
}
}
// hack to differentiate between string and binary
if (ttype == 100 && field.type == TType.STRING) {
return protocol_.readBinary();
}
}
return null;
} catch (Exception e) {
throw new TException(e);
} finally {
trans_.clear();
protocol_.reset();
}
}
private TField locateField(byte[] bytes, TFieldIdEnum fieldIdPathFirst, TFieldIdEnum ... fieldIdPathRest) throws TException {
trans_.reset(bytes);
TFieldIdEnum[] fieldIdPath = new TFieldIdEnum[fieldIdPathRest.length + 1];
fieldIdPath[0] = fieldIdPathFirst;
System.arraycopy(fieldIdPathRest, 0, fieldIdPath, 1, fieldIdPathRest.length);
// index into field ID path being currently searched for
int curPathIndex = 0;
// this will be the located field, or null if it is not located
TField field = null;
protocol_.readStructBegin();
while (curPathIndex < fieldIdPath.length) {
field = protocol_.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 null;
}
if (field.id != fieldIdPath[curPathIndex].getThriftFieldId()) {
// Not the field we're looking for. Skip field.
TProtocolUtil.skip(protocol_, field.type);
protocol_.readFieldEnd();
} else {
// This field is the next step in the path. Step into field.
curPathIndex++;
if (curPathIndex < fieldIdPath.length) {
protocol_.readStructBegin();
}
}
}
return field;
}
/**
* 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
* @throws TException if an error is encountered during deserialization.
*/
public void fromString(TBase base, String data) throws TException {
deserialize(base, data.getBytes());
}
// ----------------------------------------------------------------------
// Methods related to partial deserialization.
/**
* Partially deserializes the given serialized blob.
*
* @param bytes the serialized blob.
* @return deserialized instance.
* @throws TException if an error is encountered during deserialization.
*/
public Object partialDeserializeObject(byte[] bytes) throws TException {
return this.partialDeserializeObject(bytes, 0, bytes.length);
}
/**
* Partially deserializes the given serialized blob into the given {@code TBase} instance.
*
* @param base the instance into which the given blob is deserialized.
* @param bytes the serialized blob.
* @param offset the blob is read starting at this offset.
* @param length the size of blob read (in number of bytes).
* @return deserialized instance.
* @throws TException if an error is encountered during deserialization.
*/
public Object partialDeserializeThriftObject(TBase base, byte[] bytes, int offset, int length)
throws TException {
ensurePartialThriftDeserializationMode();
return this.partialDeserializeObject(base, bytes, offset, length);
}
/**
* Partially deserializes the given serialized blob.
*
* @param bytes the serialized blob.
* @param offset the blob is read starting at this offset.
* @param length the size of blob read (in number of bytes).
* @return deserialized instance.
* @throws TException if an error is encountered during deserialization.
*/
public Object partialDeserializeObject(byte[] bytes, int offset, int length) throws TException {
ensurePartialDeserializationMode();
return this.partialDeserializeObject(null, bytes, offset, length);
}
/**
* Partially deserializes the given serialized blob.
*
* @param instance the instance into which the given blob is deserialized.
* @param bytes the serialized blob.
* @param offset the blob is read starting at this offset.
* @param length the size of blob read (in number of bytes).
* @return deserialized instance.
* @throws TException if an error is encountered during deserialization.
*/
private Object partialDeserializeObject(Object instance, byte[] bytes, int offset, int length)
throws TException {
ensurePartialDeserializationMode();
this.trans_.reset(bytes, offset, length);
this.protocol_.reset();
return this.deserializeStruct(instance, this.metadata_);
}
private Object deserialize(ThriftMetadata.ThriftObject data) throws TException {
Object value;
byte fieldType = data.data.valueMetaData.type;
switch (fieldType) {
case TType.STRUCT:
return this.deserializeStruct(null, (ThriftMetadata.ThriftStruct) data);
case TType.LIST:
return this.deserializeList((ThriftMetadata.ThriftList) data);
case TType.MAP:
return this.deserializeMap((ThriftMetadata.ThriftMap) data);
case TType.SET:
return this.deserializeSet((ThriftMetadata.ThriftSet) data);
case TType.ENUM:
return this.deserializeEnum((ThriftMetadata.ThriftEnum) data);
case TType.BOOL:
return this.protocol_.readBool();
case TType.BYTE:
return this.protocol_.readByte();
case TType.I16:
return this.protocol_.readI16();
case TType.I32:
return this.protocol_.readI32();
case TType.I64:
return this.protocol_.readI64();
case TType.DOUBLE:
return this.protocol_.readDouble();
case TType.STRING:
if (((ThriftMetadata.ThriftPrimitive) data).isBinary()) {
return this.processor_.prepareBinary(this.protocol_.readBinary());
} else {
return this.processor_.prepareString(this.protocol_.readBinary());
}
default:
throw unsupportedFieldTypeException(fieldType);
}
}
private Object deserializeStruct(Object instance, ThriftMetadata.ThriftStruct data)
throws TException {
if (instance == null) {
instance = this.processor_.createNewStruct(data);
}
this.protocol_.readStructBegin();
while (true) {
int tfieldData = this.protocol_.readFieldBeginData();
byte tfieldType = TFieldData.getType(tfieldData);
if (tfieldType == TType.STOP) {
break;
}
Integer id = (int) TFieldData.getId(tfieldData);
ThriftMetadata.ThriftObject field = (ThriftMetadata.ThriftObject) data.fields.get(id);
if (field != null) {
this.deserializeStructField(instance, field.fieldId, field);
} else {
this.protocol_.skip(tfieldType);
}
this.protocol_.readFieldEnd();
}
this.protocol_.readStructEnd();
return this.processor_.prepareStruct(instance);
}
private void deserializeStructField(
Object instance,
TFieldIdEnum fieldId,
ThriftMetadata.ThriftObject data) throws TException {
byte fieldType = data.data.valueMetaData.type;
Object value;
switch (fieldType) {
case TType.BOOL:
this.processor_.setBool(instance, fieldId, this.protocol_.readBool());
break;
case TType.BYTE:
this.processor_.setByte(instance, fieldId, this.protocol_.readByte());
break;
case TType.I16:
this.processor_.setInt16(instance, fieldId, this.protocol_.readI16());
break;
case TType.I32:
this.processor_.setInt32(instance, fieldId, this.protocol_.readI32());
break;
case TType.I64:
this.processor_.setInt64(instance, fieldId, this.protocol_.readI64());
break;
case TType.DOUBLE:
this.processor_.setDouble(instance, fieldId, this.protocol_.readDouble());
break;
case TType.STRING:
if (((ThriftMetadata.ThriftPrimitive) data).isBinary()) {
this.processor_.setBinary(instance, fieldId, this.protocol_.readBinary());
} else {
this.processor_.setString(instance, fieldId, this.protocol_.readBinary());
}
break;
case TType.STRUCT:
value = this.deserializeStruct(null, (ThriftMetadata.ThriftStruct) data);
this.processor_.setStructField(instance, fieldId, value);
break;
case TType.LIST:
value = this.deserializeList((ThriftMetadata.ThriftList) data);
this.processor_.setListField(instance, fieldId, value);
break;
case TType.MAP:
value = this.deserializeMap((ThriftMetadata.ThriftMap) data);
this.processor_.setMapField(instance, fieldId, value);
break;
case TType.SET:
value = this.deserializeSet((ThriftMetadata.ThriftSet) data);
this.processor_.setSetField(instance, fieldId, value);
break;
case TType.ENUM:
value = this.deserializeEnum((ThriftMetadata.ThriftEnum) data);
this.processor_.setEnumField(instance, fieldId, value);
break;
default:
throw new RuntimeException("Unsupported field type: " + fieldId.toString());
}
}
private Object deserializeList(ThriftMetadata.ThriftList data) throws TException {
TList tlist = this.protocol_.readListBegin();
Object instance = this.processor_.createNewList(tlist.size);
for (int i = 0; i < tlist.size; i++) {
Object value = this.deserialize(data.elementData);
this.processor_.setListElement(instance, i, value);
}
this.protocol_.readListEnd();
return this.processor_.prepareList(instance);
}
private Object deserializeMap(ThriftMetadata.ThriftMap data) throws TException {
TMap tmap = this.protocol_.readMapBegin();
Object instance = this.processor_.createNewMap(tmap.size);
for (int i = 0; i < tmap.size; i++) {
Object key = this.deserialize(data.keyData);
Object val = this.deserialize(data.valueData);
this.processor_.setMapElement(instance, i, key, val);
}
this.protocol_.readMapEnd();
return this.processor_.prepareMap(instance);
}
private Object deserializeSet(ThriftMetadata.ThriftSet data) throws TException {
TSet tset = this.protocol_.readSetBegin();
Object instance = this.processor_.createNewSet(tset.size);
for (int i = 0; i < tset.size; i++) {
Object eltValue = this.deserialize(data.elementData);
this.processor_.setSetElement(instance, i, eltValue);
}
this.protocol_.readSetEnd();
return this.processor_.prepareSet(instance);
}
private Object deserializeEnum(ThriftMetadata.ThriftEnum data) throws TException {
int ordinal = this.protocol_.readI32();
Class enumClass = ((EnumMetaData) data.data.valueMetaData).enumClass;
return this.processor_.prepareEnum(enumClass, ordinal);
}
private Class getStructClass(ThriftMetadata.ThriftStruct data) {
return (Class) ((StructMetaData) data.data.valueMetaData).structClass;
}
private static UnsupportedOperationException unsupportedFieldTypeException(byte fieldType) {
return new UnsupportedOperationException("field type not supported: " + fieldType);
}
private boolean isPartialDeserializationMode() {
return (this.metadata_ != null) && (this.processor_ != null);
}
private void ensurePartialDeserializationMode() throws IllegalStateException {
if (!this.isPartialDeserializationMode()) {
throw new IllegalStateException(
"Members metadata and processor must be correctly initialized in order to use this method"
);
}
}
private void ensurePartialThriftDeserializationMode() throws IllegalStateException {
this.ensurePartialDeserializationMode();
if (!(this.processor_ instanceof ThriftStructProcessor)) {
throw new IllegalStateException(
"processor must be an instance of ThriftStructProcessor to use this method"
);
}
}
}