| <!DOCTYPE HTML> |
| <html lang="en"> |
| <head> |
| <!-- Generated by javadoc (17) --> |
| <title>Source code</title> |
| <meta name="viewport" content="width=device-width, initial-scale=1"> |
| <meta name="description" content="source: package: org.apache.hadoop.hbase, interface: CellScanner"> |
| <meta name="generator" content="javadoc/SourceToHTMLConverter"> |
| <link rel="stylesheet" type="text/css" href="../../../../../stylesheet.css" title="Style"> |
| </head> |
| <body class="source-page"> |
| <main role="main"> |
| <div class="source-container"> |
| <pre><span class="source-line-no">001</span><span id="line-1">/*</span> |
| <span class="source-line-no">002</span><span id="line-2"> * Licensed to the Apache Software Foundation (ASF) under one</span> |
| <span class="source-line-no">003</span><span id="line-3"> * or more contributor license agreements. See the NOTICE file</span> |
| <span class="source-line-no">004</span><span id="line-4"> * distributed with this work for additional information</span> |
| <span class="source-line-no">005</span><span id="line-5"> * regarding copyright ownership. The ASF licenses this file</span> |
| <span class="source-line-no">006</span><span id="line-6"> * to you under the Apache License, Version 2.0 (the</span> |
| <span class="source-line-no">007</span><span id="line-7"> * "License"); you may not use this file except in compliance</span> |
| <span class="source-line-no">008</span><span id="line-8"> * with the License. You may obtain a copy of the License at</span> |
| <span class="source-line-no">009</span><span id="line-9"> *</span> |
| <span class="source-line-no">010</span><span id="line-10"> * http://www.apache.org/licenses/LICENSE-2.0</span> |
| <span class="source-line-no">011</span><span id="line-11"> *</span> |
| <span class="source-line-no">012</span><span id="line-12"> * Unless required by applicable law or agreed to in writing, software</span> |
| <span class="source-line-no">013</span><span id="line-13"> * distributed under the License is distributed on an "AS IS" BASIS,</span> |
| <span class="source-line-no">014</span><span id="line-14"> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</span> |
| <span class="source-line-no">015</span><span id="line-15"> * See the License for the specific language governing permissions and</span> |
| <span class="source-line-no">016</span><span id="line-16"> * limitations under the License.</span> |
| <span class="source-line-no">017</span><span id="line-17"> */</span> |
| <span class="source-line-no">018</span><span id="line-18">package org.apache.hadoop.hbase;</span> |
| <span class="source-line-no">019</span><span id="line-19"></span> |
| <span class="source-line-no">020</span><span id="line-20">import java.io.IOException;</span> |
| <span class="source-line-no">021</span><span id="line-21">import org.apache.yetus.audience.InterfaceAudience;</span> |
| <span class="source-line-no">022</span><span id="line-22"></span> |
| <span class="source-line-no">023</span><span id="line-23">/**</span> |
| <span class="source-line-no">024</span><span id="line-24"> * An interface for iterating through a sequence of cells. Similar to Java's Iterator, but without</span> |
| <span class="source-line-no">025</span><span id="line-25"> * the hasNext() or remove() methods. The hasNext() method is problematic because it may require</span> |
| <span class="source-line-no">026</span><span id="line-26"> * actually loading the next object, which in turn requires storing the previous object somewhere.</span> |
| <span class="source-line-no">027</span><span id="line-27"> * <p></span> |
| <span class="source-line-no">028</span><span id="line-28"> * The core data block decoder should be as fast as possible, so we push the complexity and</span> |
| <span class="source-line-no">029</span><span id="line-29"> * performance expense of concurrently tracking multiple cells to layers above the CellScanner.</span> |
| <span class="source-line-no">030</span><span id="line-30"> * <p></span> |
| <span class="source-line-no">031</span><span id="line-31"> * The {@link #current()} method will return a reference to a Cell implementation. This reference</span> |
| <span class="source-line-no">032</span><span id="line-32"> * may or may not point to a reusable cell implementation, so users of the CellScanner should not,</span> |
| <span class="source-line-no">033</span><span id="line-33"> * for example, accumulate a List of Cells. All of the references may point to the same object,</span> |
| <span class="source-line-no">034</span><span id="line-34"> * which would be the latest state of the underlying Cell. In short, the Cell is mutable.</span> |
| <span class="source-line-no">035</span><span id="line-35"> * </p></span> |
| <span class="source-line-no">036</span><span id="line-36"> * Typical usage:</span> |
| <span class="source-line-no">037</span><span id="line-37"> *</span> |
| <span class="source-line-no">038</span><span id="line-38"> * <pre></span> |
| <span class="source-line-no">039</span><span id="line-39"> * while (scanner.advance()) {</span> |
| <span class="source-line-no">040</span><span id="line-40"> * Cell cell = scanner.current();</span> |
| <span class="source-line-no">041</span><span id="line-41"> * // do something</span> |
| <span class="source-line-no">042</span><span id="line-42"> * }</span> |
| <span class="source-line-no">043</span><span id="line-43"> * </pre></span> |
| <span class="source-line-no">044</span><span id="line-44"> * <p></span> |
| <span class="source-line-no">045</span><span id="line-45"> * Often used reading {@link org.apache.hadoop.hbase.Cell}s written by</span> |
| <span class="source-line-no">046</span><span id="line-46"> * {@link org.apache.hadoop.hbase.io.CellOutputStream}.</span> |
| <span class="source-line-no">047</span><span id="line-47"> */</span> |
| <span class="source-line-no">048</span><span id="line-48">@InterfaceAudience.Public</span> |
| <span class="source-line-no">049</span><span id="line-49">public interface CellScanner {</span> |
| <span class="source-line-no">050</span><span id="line-50"> /** Returns the current Cell which may be mutable */</span> |
| <span class="source-line-no">051</span><span id="line-51"> Cell current();</span> |
| <span class="source-line-no">052</span><span id="line-52"></span> |
| <span class="source-line-no">053</span><span id="line-53"> /**</span> |
| <span class="source-line-no">054</span><span id="line-54"> * Advance the scanner 1 cell.</span> |
| <span class="source-line-no">055</span><span id="line-55"> * @return true if the next cell is found and {@link #current()} will return a valid Cell</span> |
| <span class="source-line-no">056</span><span id="line-56"> * @throws IOException if advancing the scanner fails</span> |
| <span class="source-line-no">057</span><span id="line-57"> */</span> |
| <span class="source-line-no">058</span><span id="line-58"> boolean advance() throws IOException;</span> |
| <span class="source-line-no">059</span><span id="line-59">}</span> |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| </pre> |
| </div> |
| </main> |
| </body> |
| </html> |
