org.apache.hadoop.record.meta.RecordTypeInfo Maven / Gradle / Ivy
/**
* 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.hadoop.record.meta;
import java.io.IOException;
import java.util.*;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.record.RecordInput;
import org.apache.hadoop.record.RecordOutput;
/**
* A record's Type Information object which can read/write itself.
*
* Type information for a record comprises metadata about the record,
* as well as a collection of type information for each field in the record.
*
* @deprecated Replaced by Avro.
*/
@Deprecated
@InterfaceAudience.Public
@InterfaceStability.Stable
public class RecordTypeInfo extends org.apache.hadoop.record.Record
{
private String name;
// A RecordTypeInfo is really just a wrapper around StructTypeID
StructTypeID sTid;
// A RecordTypeInfo object is just a collection of TypeInfo objects for each of its fields.
//private ArrayList typeInfos = new ArrayList();
// we keep a hashmap of struct/record names and their type information, as we need it to
// set filters when reading nested structs. This map is used during deserialization.
//private Map structRTIs = new HashMap();
/**
* Create an empty RecordTypeInfo object.
*/
public RecordTypeInfo() {
sTid = new StructTypeID();
}
/**
* Create a RecordTypeInfo object representing a record with the given name
* @param name Name of the record
*/
public RecordTypeInfo(String name) {
this.name = name;
sTid = new StructTypeID();
}
/*
* private constructor
*/
private RecordTypeInfo(String name, StructTypeID stid) {
this.sTid = stid;
this.name = name;
}
/**
* return the name of the record
*/
public String getName() {
return name;
}
/**
* set the name of the record
*/
public void setName(String name) {
this.name = name;
}
/**
* Add a field.
* @param fieldName Name of the field
* @param tid Type ID of the field
*/
public void addField(String fieldName, TypeID tid) {
sTid.getFieldTypeInfos().add(new FieldTypeInfo(fieldName, tid));
}
private void addAll(Collection tis) {
sTid.getFieldTypeInfos().addAll(tis);
}
/**
* Return a collection of field type infos
*/
public Collection getFieldTypeInfos() {
return sTid.getFieldTypeInfos();
}
/**
* Return the type info of a nested record. We only consider nesting
* to one level.
* @param name Name of the nested record
*/
public RecordTypeInfo getNestedStructTypeInfo(String name) {
StructTypeID stid = sTid.findStruct(name);
if (null == stid) return null;
return new RecordTypeInfo(name, stid);
}
/**
* Serialize the type information for a record
*/
@Override
public void serialize(RecordOutput rout, String tag) throws IOException {
// write out any header, version info, here
rout.startRecord(this, tag);
rout.writeString(name, tag);
sTid.writeRest(rout, tag);
rout.endRecord(this, tag);
}
/**
* Deserialize the type information for a record
*/
@Override
public void deserialize(RecordInput rin, String tag) throws IOException {
// read in any header, version info
rin.startRecord(tag);
// name
this.name = rin.readString(tag);
sTid.read(rin, tag);
rin.endRecord(tag);
}
/**
* This class doesn't implement Comparable as it's not meant to be used
* for anything besides de/serializing.
* So we always throw an exception.
* Not implemented. Always returns 0 if another RecordTypeInfo is passed in.
*/
@Override
public int compareTo (final Object peer_) throws ClassCastException {
if (!(peer_ instanceof RecordTypeInfo)) {
throw new ClassCastException("Comparing different types of records.");
}
throw new UnsupportedOperationException("compareTo() is not supported");
}
}