| /** |
| * 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.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. |
| */ |
| 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<FieldTypeInfo> typeInfos = new ArrayList<FieldTypeInfo>(); |
| // 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<String, RecordTypeInfo> structRTIs = new HashMap<String, RecordTypeInfo>(); |
| |
| /** |
| * 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<FieldTypeInfo> tis) { |
| sTid.getFieldTypeInfos().addAll(tis); |
| } |
| |
| /** |
| * Return a collection of field type infos |
| */ |
| public Collection<FieldTypeInfo> 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 |
| */ |
| 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 |
| */ |
| 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. |
| */ |
| 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"); |
| } |
| } |
| |