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 com.facebook.infrastructure.db; import com.facebook.infrastructure.io.ICompactSerializer; import com.facebook.infrastructure.service.*; import com.facebook.infrastructure.net.Message; import com.facebook.infrastructure.net.EndPoint; import com.facebook.infrastructure.utils.FBUtilities; import java.io.*; import java.util.*; import java.util.concurrent.ExecutionException; import org.apache.commons.lang.ArrayUtils; import org.apache.commons.lang.StringUtils; /** * Author : Avinash Lakshman ( alakshman@facebook.com) & Prashant Malik ( pmalik@facebook.com ) */ public class RowMutation implements Serializable { private static ICompactSerializer<RowMutation> serializer_; public static final String HINT = "HINT"; static { serializer_ = new RowMutationSerializer(); } static ICompactSerializer<RowMutation> serializer() { return serializer_; } private String table_; private String key_; protected Map<String, ColumnFamily> modifications_ = new HashMap<String, ColumnFamily>(); /* Ctor for JAXB */ private RowMutation() { } public RowMutation(String table, String key) { table_ = table; key_ = key; } public RowMutation(String table, Row row) { table_ = table; key_ = row.key(); for (ColumnFamily cf : row.getColumnFamilies()) { add(cf); } } protected RowMutation(String table, String key, Map<String, ColumnFamily> modifications) { table_ = table; key_ = key; modifications_ = modifications; } public Message makeRowMutationMessage() throws IOException { return makeRowMutationMessage(StorageService.mutationVerbHandler_); } public Message makeRowMutationMessage(String verbHandlerName) throws IOException { ByteArrayOutputStream bos = new ByteArrayOutputStream(); DataOutputStream dos = new DataOutputStream(bos); serializer().serialize(this, dos); EndPoint local = StorageService.getLocalStorageEndPoint(); EndPoint from = (local != null) ? local : new EndPoint(FBUtilities.getHostName(), 7000); Message message = new Message(from, StorageService.mutationStage_, verbHandlerName, bos.toByteArray()); return message; } public static String[] getColumnAndColumnFamily(String cf) { return cf.split(":"); } String table() { return table_; } public String key() { return key_; } void addHints(String hint) throws IOException, ColumnFamilyNotDefinedException { String cfName = Table.hints_ + ":" + hint; add(cfName, ArrayUtils.EMPTY_BYTE_ARRAY, 0); } /* * Specify a column family name and the corresponding column * family object. * param @ cf - column family name * param @ columnFamily - the column family. */ public void add(ColumnFamily columnFamily) { if (modifications_.containsKey(columnFamily.name())) { throw new IllegalArgumentException( "ColumnFamily " + columnFamily.name() + " is already being modified"); } modifications_.put(columnFamily.name(), columnFamily); } /* * Specify a column name and a corresponding value for * the column. Column name is specified as <column family>:column. * This will result in a ColumnFamily associated with * <column family> as name and a Column with <column> * as name. The columan can be further broken up * as super column name : columnname in case of super columns * * param @ cf - column name as <column family>:<column> * param @ value - value associated with the column * param @ timestamp - ts associated with this data. */ public void add(String columnFamilyColumn, byte[] value, long timestamp) { String[] values = RowMutation.getColumnAndColumnFamily(columnFamilyColumn); String cfName = values[0]; if (values.length == 0 || values.length == 1 || values.length > 3) throw new IllegalArgumentException("Column Family " + columnFamilyColumn + " in invalid format. Must be in <column family>:<column> format."); ColumnFamily columnFamily = modifications_.get(cfName); if (values.length == 2) { if (columnFamily == null) { columnFamily = new ColumnFamily(cfName, ColumnFamily.getColumnType("Standard")); } else { if (columnFamily.getColumn(values[1]) != null) { throw new IllegalArgumentException(columnFamilyColumn + " is already being modified"); } } columnFamily.addColumn(values[1], value, timestamp); } if (values.length == 3) { if (columnFamily == null) { columnFamily = new ColumnFamily(cfName, ColumnFamily.getColumnType("Super")); } else { IColumn sc = columnFamily.getColumn(values[1]); if (sc != null && ((SuperColumn) sc).getSubColumn(values[2]) != null) { throw new IllegalArgumentException(columnFamilyColumn + " is already being modified"); } } columnFamily.addColumn(values[1] + ":" + values[2], value, timestamp); } modifications_.put(cfName, columnFamily); } /* * Specify a column name to be deleted. Column name is * specified as <column family>:column. This will result * in a ColumnFamily associated with <column family> as * name and perhaps Column with <column> as name being * marked as deleted. * param @ cf - column name as <column family>:<column> */ public void delete(String columnFamilyColumn, long timestamp) { String[] values = RowMutation.getColumnAndColumnFamily(columnFamilyColumn); String cfName = values[0]; if (modifications_.containsKey(cfName)) { throw new IllegalArgumentException("ColumnFamily " + cfName + " is already being modified"); } if (values.length == 0 || values.length > 3) throw new IllegalArgumentException("Column Family " + columnFamilyColumn + " in invalid format. Must be in <column family>:<column> format."); ColumnFamily columnFamily = modifications_.get(cfName); if (columnFamily == null) columnFamily = new ColumnFamily(cfName); if (values.length == 2) { if (columnFamily.isSuper()) { IColumn c = columnFamily.addColumn(values[1]); ((SuperColumn) c).markForDeleteAt(timestamp); } else { IColumn c = columnFamily.addColumn(values[1], ArrayUtils.EMPTY_BYTE_ARRAY, timestamp, true); } } else if (values.length == 3) { IColumn c = columnFamily.addColumn(values[1] + ":" + values[2], ArrayUtils.EMPTY_BYTE_ARRAY, timestamp, true); } else { assert values.length == 1; columnFamily.delete(timestamp); } modifications_.put(cfName, columnFamily); } /* * This is equivalent to calling commit. Applies the changes to * to the table that is obtained by calling Table.open(). */ public void apply() throws IOException, ColumnFamilyNotDefinedException { Row row = new Row(key_); apply(row); } /* * Allows RowMutationVerbHandler to optimize by re-using a single Row object. */ void apply(Row emptyRow) throws IOException, ColumnFamilyNotDefinedException { assert emptyRow.getColumnFamilies().size() == 0; Table table = Table.open(table_); for (String cfName : modifications_.keySet()) { if (!table.isValidColumnFamily(cfName)) throw new ColumnFamilyNotDefinedException("Column Family " + cfName + " has not been defined."); emptyRow.addColumnFamily(modifications_.get(cfName)); } table.apply(emptyRow); } /* * This is equivalent to calling commit. Applies the changes to * to the table that is obtained by calling Table.open(). */ void load(Row row) throws IOException, ColumnFamilyNotDefinedException, ExecutionException, InterruptedException { Table table = Table.open(table_); Set<String> cfNames = modifications_.keySet(); for (String cfName : cfNames) { if (!table.isValidColumnFamily(cfName)) throw new ColumnFamilyNotDefinedException("Column Family " + cfName + " has not been defined."); row.addColumnFamily(modifications_.get(cfName)); } table.load(row); } public static RowMutation getRowMutation(batch_mutation_t batchMutation) { RowMutation rm = new RowMutation(batchMutation.table, batchMutation.key.trim()); for (String cfname : batchMutation.cfmap.keySet()) { List<column_t> list = batchMutation.cfmap.get(cfname); for (column_t columnData : list) { rm.add(cfname + ":" + columnData.columnName, columnData.value.getBytes(), columnData.timestamp); } } return rm; } public static RowMutation getRowMutation(batch_mutation_super_t batchMutationSuper) { RowMutation rm = new RowMutation(batchMutationSuper.table, batchMutationSuper.key.trim()); Set keys = batchMutationSuper.cfmap.keySet(); Iterator keyIter = keys.iterator(); while (keyIter.hasNext()) { Object key = keyIter.next(); // Get the next key. List<superColumn_t> list = batchMutationSuper.cfmap.get(key); for (superColumn_t superColumnData : list) { if (superColumnData.columns.size() != 0) { for (column_t columnData : superColumnData.columns) { rm.add(key.toString() + ":" + superColumnData.name + ":" + columnData.columnName, columnData.value.getBytes(), columnData.timestamp); } } else { rm.add(key.toString() + ":" + superColumnData.name, ArrayUtils.EMPTY_BYTE_ARRAY, 0); } } } return rm; } public String toString() { return "RowMutation(" + "key='" + key_ + '\'' + ", modifications=[" + StringUtils.join(modifications_.values(), ", ") + "]" + ')'; } } class RowMutationSerializer implements ICompactSerializer<RowMutation> { private void freezeTheMaps(Map<String, ColumnFamily> map, DataOutputStream dos) throws IOException { int size = map.size(); dos.writeInt(size); if (size > 0) { Set<String> keys = map.keySet(); for (String key : keys) { dos.writeUTF(key); ColumnFamily cf = map.get(key); if (cf != null) { ColumnFamily.serializer().serialize(cf, dos); } } } } public void serialize(RowMutation rm, DataOutputStream dos) throws IOException { dos.writeUTF(rm.table()); dos.writeUTF(rm.key()); /* serialize the modifications_ in the mutation */ freezeTheMaps(rm.modifications_, dos); } private Map<String, ColumnFamily> defreezeTheMaps(DataInputStream dis) throws IOException { Map<String, ColumnFamily> map = new HashMap<String, ColumnFamily>(); int size = dis.readInt(); for (int i = 0; i < size; ++i) { String key = dis.readUTF(); ColumnFamily cf = ColumnFamily.serializer().deserialize(dis); map.put(key, cf); } return map; } public RowMutation deserialize(DataInputStream dis) throws IOException { String table = dis.readUTF(); String key = dis.readUTF(); Map<String, ColumnFamily> modifications = defreezeTheMaps(dis); return new RowMutation(table, key, modifications); } }