| /* |
| * 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.fluo.api.client; |
| |
| import java.util.Collection; |
| import java.util.Map; |
| import java.util.Set; |
| |
| import org.apache.fluo.api.client.scanner.ScannerBuilder; |
| import org.apache.fluo.api.data.Bytes; |
| import org.apache.fluo.api.data.Column; |
| import org.apache.fluo.api.data.RowColumn; |
| import org.apache.fluo.api.data.Span; |
| |
| /** |
| * Allows users to read from a Fluo table at a certain point in time |
| * |
| * @since 1.0.0 |
| * @see AbstractSnapshotBase |
| */ |
| public interface SnapshotBase { |
| |
| /** |
| * Retrieves the value (in {@link Bytes}) stored at a given row and {@link Column}. Returns null |
| * if does not exist. |
| */ |
| Bytes get(Bytes row, Column column); |
| |
| /** |
| * Retrieves the value (in {@link Bytes}) stored at a given row and {@link Column}. Returns the |
| * passed in defaultValue if does not exist. |
| * |
| * @param defaultValue this will be returned if row+columns does not exists |
| */ |
| Bytes get(Bytes row, Column column, Bytes defaultValue); |
| |
| /** |
| * Given a row and set of {@link Column}s, retrieves a map that contains the values at those |
| * {@link Column}s. Only columns that exist will be returned in map. |
| */ |
| Map<Column, Bytes> get(Bytes row, Set<Column> columns); |
| |
| /** |
| * Given a row and list of {@link Column}s, retrieves a map that contains the values at those |
| * {@link Column}s. Only columns that exist will be returned in map. |
| */ |
| Map<Column, Bytes> get(Bytes row, Column... columns); |
| |
| /** |
| * Given a collection of rows and set of {@link Column}s, retrieves a map that contains the values |
| * at those rows and {@link Column}s. Only rows and columns that exists will be returned in map. |
| */ |
| Map<Bytes, Map<Column, Bytes>> get(Collection<Bytes> rows, Set<Column> columns); |
| |
| /** |
| * Given a collection of rows and list of {@link Column}s, retrieves a map that contains the |
| * values at those rows and {@link Column}s. Only rows and columns that exists will be returned in |
| * map. |
| */ |
| Map<Bytes, Map<Column, Bytes>> get(Collection<Bytes> rows, Column... columns); |
| |
| |
| /** |
| * Given a collection of {@link RowColumn}s, retrieves a map contains the values at |
| * {@link RowColumn}. Only rows and columns that exists will be returned in map. |
| */ |
| Map<RowColumn, Bytes> get(Collection<RowColumn> rowColumns); |
| |
| /** |
| * This method is the starting point for constructing a scanner. Scanners can be constructed over |
| * a {@link Span} and/or with a subset of columns. Below is simple example of building a scanner. |
| * |
| * <pre> |
| * <code> |
| * Transaction tx = ...; |
| * Span span = Span.exact("row4"); |
| * Column col1 = new Column("fam1","qual1"); |
| * Column col2 = new Column("fam1","qual2"); |
| * |
| * //create a scanner over row4 fetching columns fam1:qual1 and fam1:qual2 |
| * CellScanner cs = tx.scanner().over(span).fetch(col1,col2).build(); |
| * for(RowColumnValue rcv : cs) { |
| * //do stuff with rcv |
| * } |
| * </code> |
| * </pre> |
| * |
| * <p> |
| * The following example shows how to build a row scanner. |
| * |
| * <pre> |
| * <code> |
| * RowScanner rs = tx.scanner().over(span).fetch(col1, col2).byRow().build(); |
| * for (ColumnScanner colScanner : rs) { |
| * Bytes row = colScanner.getRow(); |
| * for (ColumnValue cv : colScanner) { |
| * // do stuff with the columns and values in the row |
| * } |
| * } |
| * </code> |
| * </pre> |
| * |
| * @return A scanner builder. |
| * @see TransactionBase#withReadLock() |
| */ |
| |
| ScannerBuilder scanner(); |
| |
| /** |
| * Wrapper for {@link #get(Collection)} that uses Strings. All strings are encoded and decoded |
| * using UTF-8. |
| */ |
| Map<RowColumn, String> gets(Collection<RowColumn> rowColumns); |
| |
| /** |
| * Wrapper for {@link #get(Collection, Set)} that uses Strings. All strings are encoded and |
| * decoded using UTF-8. |
| */ |
| Map<String, Map<Column, String>> gets(Collection<? extends CharSequence> rows, |
| Set<Column> columns); |
| |
| /** |
| * Wrapper for {@link #get(Collection, Set)} that uses Strings. All strings are encoded and |
| * decoded using UTF-8. |
| */ |
| Map<String, Map<Column, String>> gets(Collection<? extends CharSequence> rows, Column... columns); |
| |
| /** |
| * Wrapper for {@link #get(Bytes, Column)} that uses Strings. All strings are encoded and decoded |
| * using UTF-8. |
| */ |
| String gets(CharSequence row, Column column); |
| |
| /** |
| * Wrapper for {@link #get(Bytes, Column, Bytes)} that uses Strings. All strings are encoded and |
| * decoded using UTF-8. |
| */ |
| String gets(CharSequence row, Column column, String defaultValue); |
| |
| /** |
| * Wrapper for {@link #get(Bytes, Set)} that uses Strings. All strings are encoded and decoded |
| * using UTF-8. |
| */ |
| Map<Column, String> gets(CharSequence row, Set<Column> columns); |
| |
| /** |
| * Wrapper for {@link #get(Bytes, Set)} that uses Strings. All strings are encoded and decoded |
| * using UTF-8. |
| */ |
| Map<Column, String> gets(CharSequence row, Column... columns); |
| |
| /** |
| * @return transactions start timestamp allocated from Oracle. |
| */ |
| long getStartTimestamp(); |
| } |