Java tutorial
/** * 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.hive.metastore.messaging.json; import java.util.ArrayList; import java.util.Iterator; import java.util.LinkedHashMap; import java.util.List; import java.util.Map; import javax.annotation.Nullable; import org.apache.hadoop.hive.metastore.api.Database; import org.apache.hadoop.hive.metastore.api.Function; import org.apache.hadoop.hive.metastore.api.Index; import org.apache.hadoop.hive.metastore.api.NotificationEvent; import org.apache.hadoop.hive.metastore.api.Partition; import org.apache.hadoop.hive.metastore.api.Table; import org.apache.hadoop.hive.metastore.messaging.AddPartitionMessage; import org.apache.hadoop.hive.metastore.messaging.AlterIndexMessage; import org.apache.hadoop.hive.metastore.messaging.AlterPartitionMessage; import org.apache.hadoop.hive.metastore.messaging.AlterTableMessage; import org.apache.hadoop.hive.metastore.messaging.CreateDatabaseMessage; import org.apache.hadoop.hive.metastore.messaging.CreateFunctionMessage; import org.apache.hadoop.hive.metastore.messaging.CreateIndexMessage; import org.apache.hadoop.hive.metastore.messaging.CreateTableMessage; import org.apache.hadoop.hive.metastore.messaging.DropDatabaseMessage; import org.apache.hadoop.hive.metastore.messaging.DropFunctionMessage; import org.apache.hadoop.hive.metastore.messaging.DropIndexMessage; import org.apache.hadoop.hive.metastore.messaging.DropPartitionMessage; import org.apache.hadoop.hive.metastore.messaging.DropTableMessage; import org.apache.hadoop.hive.metastore.messaging.InsertMessage; import org.apache.hadoop.hive.metastore.messaging.MessageDeserializer; import org.apache.hadoop.hive.metastore.messaging.MessageFactory; import org.apache.thrift.TDeserializer; import org.apache.thrift.TException; import org.apache.thrift.TSerializer; import org.apache.thrift.protocol.TJSONProtocol; import org.codehaus.jackson.JsonFactory; import org.codehaus.jackson.JsonNode; import org.codehaus.jackson.JsonParser; import org.codehaus.jackson.map.ObjectMapper; import org.codehaus.jackson.node.ObjectNode; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.google.common.collect.Iterators; import com.google.common.collect.Lists; /** * The JSON implementation of the MessageFactory. Constructs JSON implementations of each * message-type. */ public class JSONMessageFactory extends MessageFactory { private static final Logger LOG = LoggerFactory.getLogger(JSONMessageFactory.class.getName()); private static JSONMessageDeserializer deserializer = new JSONMessageDeserializer(); @Override public MessageDeserializer getDeserializer() { return deserializer; } @Override public String getVersion() { return "0.1"; } @Override public String getMessageFormat() { return "json"; } @Override public CreateDatabaseMessage buildCreateDatabaseMessage(Database db) { return new JSONCreateDatabaseMessage(MS_SERVER_URL, MS_SERVICE_PRINCIPAL, db.getName(), now()); } @Override public DropDatabaseMessage buildDropDatabaseMessage(Database db) { return new JSONDropDatabaseMessage(MS_SERVER_URL, MS_SERVICE_PRINCIPAL, db.getName(), now()); } @Override public CreateTableMessage buildCreateTableMessage(Table table) { return new JSONCreateTableMessage(MS_SERVER_URL, MS_SERVICE_PRINCIPAL, table, now()); } @Override public AlterTableMessage buildAlterTableMessage(Table before, Table after) { return new JSONAlterTableMessage(MS_SERVER_URL, MS_SERVICE_PRINCIPAL, after, now()); } @Override public DropTableMessage buildDropTableMessage(Table table) { return new JSONDropTableMessage(MS_SERVER_URL, MS_SERVICE_PRINCIPAL, table.getDbName(), table.getTableName(), now()); } @Override public AddPartitionMessage buildAddPartitionMessage(Table table, Iterator<Partition> partitionsIterator) { return new JSONAddPartitionMessage(MS_SERVER_URL, MS_SERVICE_PRINCIPAL, table, partitionsIterator, now()); } @Override public AlterPartitionMessage buildAlterPartitionMessage(Table table, Partition before, Partition after) { return new JSONAlterPartitionMessage(MS_SERVER_URL, MS_SERVICE_PRINCIPAL, table, before, after, now()); } @Override public DropPartitionMessage buildDropPartitionMessage(Table table, Iterator<Partition> partitionsIterator) { return new JSONDropPartitionMessage(MS_SERVER_URL, MS_SERVICE_PRINCIPAL, table.getDbName(), table.getTableName(), getPartitionKeyValues(table, partitionsIterator), now()); } @Override public CreateFunctionMessage buildCreateFunctionMessage(Function fn) { return new JSONCreateFunctionMessage(MS_SERVER_URL, MS_SERVICE_PRINCIPAL, fn, now()); } @Override public DropFunctionMessage buildDropFunctionMessage(Function fn) { return new JSONDropFunctionMessage(MS_SERVER_URL, MS_SERVICE_PRINCIPAL, fn, now()); } @Override public CreateIndexMessage buildCreateIndexMessage(Index idx) { return new JSONCreateIndexMessage(MS_SERVER_URL, MS_SERVICE_PRINCIPAL, idx, now()); } @Override public DropIndexMessage buildDropIndexMessage(Index idx) { return new JSONDropIndexMessage(MS_SERVER_URL, MS_SERVICE_PRINCIPAL, idx, now()); } @Override public AlterIndexMessage buildAlterIndexMessage(Index before, Index after) { return new JSONAlterIndexMessage(MS_SERVER_URL, MS_SERVICE_PRINCIPAL, before, after, now()); } @Override public InsertMessage buildInsertMessage(String db, String table, Map<String, String> partKeyVals, List<String> files) { return new JSONInsertMessage(MS_SERVER_URL, MS_SERVICE_PRINCIPAL, db, table, partKeyVals, files, now()); } private long now() { return System.currentTimeMillis() / 1000; } static Map<String, String> getPartitionKeyValues(Table table, Partition partition) { Map<String, String> partitionKeys = new LinkedHashMap<String, String>(); for (int i = 0; i < table.getPartitionKeysSize(); ++i) partitionKeys.put(table.getPartitionKeys().get(i).getName(), partition.getValues().get(i)); return partitionKeys; } static List<Map<String, String>> getPartitionKeyValues(final Table table, Iterator<Partition> iterator) { return Lists.newArrayList(Iterators.transform(iterator, new com.google.common.base.Function<Partition, Map<String, String>>() { @Override public Map<String, String> apply(@Nullable Partition partition) { return getPartitionKeyValues(table, partition); } })); } static String createTableObjJson(Table tableObj) throws TException { TSerializer serializer = new TSerializer(new TJSONProtocol.Factory()); return serializer.toString(tableObj, "UTF-8"); } static String createPartitionObjJson(Partition partitionObj) throws TException { TSerializer serializer = new TSerializer(new TJSONProtocol.Factory()); return serializer.toString(partitionObj, "UTF-8"); } static String createFunctionObjJson(Function functionObj) throws TException { TSerializer serializer = new TSerializer(new TJSONProtocol.Factory()); return serializer.toString(functionObj, "UTF-8"); } static String createIndexObjJson(Index indexObj) throws TException { TSerializer serializer = new TSerializer(new TJSONProtocol.Factory()); return serializer.toString(indexObj, "UTF-8"); } public static ObjectNode getJsonTree(NotificationEvent event) throws Exception { JsonParser jsonParser = (new JsonFactory()).createJsonParser(event.getMessage()); ObjectMapper mapper = new ObjectMapper(); return mapper.readValue(jsonParser, ObjectNode.class); } public static Table getTableObj(ObjectNode jsonTree) throws Exception { TDeserializer deSerializer = new TDeserializer(new TJSONProtocol.Factory()); Table tableObj = new Table(); String tableJson = jsonTree.get("tableObjJson").asText(); deSerializer.deserialize(tableObj, tableJson, "UTF-8"); return tableObj; } public static List<Partition> getPartitionObjList(ObjectNode jsonTree) throws Exception { TDeserializer deSerializer = new TDeserializer(new TJSONProtocol.Factory()); List<Partition> partitionObjList = new ArrayList<Partition>(); Partition partitionObj = new Partition(); Iterator<JsonNode> jsonArrayIterator = jsonTree.get("partitionListJson").iterator(); while (jsonArrayIterator.hasNext()) { deSerializer.deserialize(partitionObj, jsonArrayIterator.next().asText(), "UTF-8"); partitionObjList.add(partitionObj); } return partitionObjList; } public static Function getFunctionObj(ObjectNode jsonTree) throws Exception { TDeserializer deSerializer = new TDeserializer(new TJSONProtocol.Factory()); Function funcObj = new Function(); String tableJson = jsonTree.get("functionObjJson").asText(); deSerializer.deserialize(funcObj, tableJson, "UTF-8"); return funcObj; } public static Index getIndexObj(ObjectNode jsonTree) throws Exception { return getIndexObj(jsonTree, "indexObjJson"); } public static Index getIndexObj(ObjectNode jsonTree, String indexObjKey) throws Exception { TDeserializer deSerializer = new TDeserializer(new TJSONProtocol.Factory()); Index indexObj = new Index(); String tableJson = jsonTree.get(indexObjKey).asText(); deSerializer.deserialize(indexObj, tableJson, "UTF-8"); return indexObj; } }