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From git-site-r...@apache.org
Subject [35/51] [partial] hbase-site git commit: Published site at 82d554e3783372cc6b05489452c815b57c06f6cd.
Date Fri, 07 Jul 2017 06:43:06 GMT
http://git-wip-us.apache.org/repos/asf/hbase-site/blob/b3b50f22/devapidocs/src-html/org/apache/hadoop/hbase/io/FileLink.html
----------------------------------------------------------------------
diff --git a/devapidocs/src-html/org/apache/hadoop/hbase/io/FileLink.html b/devapidocs/src-html/org/apache/hadoop/hbase/io/FileLink.html
index 6ee4990..e01933b 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/io/FileLink.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/io/FileLink.html
@@ -46,475 +46,479 @@
 <span class="sourceLineNo">038</span>import org.apache.hadoop.fs.PositionedReadable;<a name="line.38"></a>
 <span class="sourceLineNo">039</span>import org.apache.hadoop.fs.Seekable;<a name="line.39"></a>
 <span class="sourceLineNo">040</span>import org.apache.hadoop.hbase.util.FSUtils;<a name="line.40"></a>
-<span class="sourceLineNo">041</span><a name="line.41"></a>
-<span class="sourceLineNo">042</span>/**<a name="line.42"></a>
-<span class="sourceLineNo">043</span> * The FileLink is a sort of hardlink, that allows access to a file given a set of locations.<a name="line.43"></a>
-<span class="sourceLineNo">044</span> *<a name="line.44"></a>
-<span class="sourceLineNo">045</span> * &lt;p&gt;&lt;b&gt;The Problem:&lt;/b&gt;<a name="line.45"></a>
-<span class="sourceLineNo">046</span> * &lt;ul&gt;<a name="line.46"></a>
-<span class="sourceLineNo">047</span> *  &lt;li&gt;<a name="line.47"></a>
-<span class="sourceLineNo">048</span> *    HDFS doesn't have support for hardlinks, and this make impossible to referencing<a name="line.48"></a>
-<span class="sourceLineNo">049</span> *    the same data blocks using different names.<a name="line.49"></a>
-<span class="sourceLineNo">050</span> *  &lt;/li&gt;<a name="line.50"></a>
-<span class="sourceLineNo">051</span> *  &lt;li&gt;<a name="line.51"></a>
-<span class="sourceLineNo">052</span> *    HBase store files in one location (e.g. table/region/family/) and when the file is not<a name="line.52"></a>
-<span class="sourceLineNo">053</span> *    needed anymore (e.g. compaction, region deletion, ...) moves it to an archive directory.<a name="line.53"></a>
-<span class="sourceLineNo">054</span> *  &lt;/li&gt;<a name="line.54"></a>
-<span class="sourceLineNo">055</span> * &lt;/ul&gt;<a name="line.55"></a>
-<span class="sourceLineNo">056</span> * If we want to create a reference to a file, we need to remember that it can be in its<a name="line.56"></a>
-<span class="sourceLineNo">057</span> * original location or in the archive folder.<a name="line.57"></a>
-<span class="sourceLineNo">058</span> * The FileLink class tries to abstract this concept and given a set of locations<a name="line.58"></a>
-<span class="sourceLineNo">059</span> * it is able to switch between them making this operation transparent for the user.<a name="line.59"></a>
-<span class="sourceLineNo">060</span> * {@link HFileLink} is a more concrete implementation of the {@code FileLink}.<a name="line.60"></a>
-<span class="sourceLineNo">061</span> *<a name="line.61"></a>
-<span class="sourceLineNo">062</span> * &lt;p&gt;&lt;b&gt;Back-references:&lt;/b&gt;<a name="line.62"></a>
-<span class="sourceLineNo">063</span> * To help the {@link org.apache.hadoop.hbase.master.cleaner.CleanerChore} to keep track of<a name="line.63"></a>
-<span class="sourceLineNo">064</span> * the links to a particular file, during the {@code FileLink} creation, a new file is placed<a name="line.64"></a>
-<span class="sourceLineNo">065</span> * inside a back-reference directory. There's one back-reference directory for each file that<a name="line.65"></a>
-<span class="sourceLineNo">066</span> * has links, and in the directory there's one file per link.<a name="line.66"></a>
-<span class="sourceLineNo">067</span> *<a name="line.67"></a>
-<span class="sourceLineNo">068</span> * &lt;p&gt;HFileLink Example<a name="line.68"></a>
-<span class="sourceLineNo">069</span> * &lt;ul&gt;<a name="line.69"></a>
-<span class="sourceLineNo">070</span> *  &lt;li&gt;<a name="line.70"></a>
-<span class="sourceLineNo">071</span> *      /hbase/table/region-x/cf/file-k<a name="line.71"></a>
-<span class="sourceLineNo">072</span> *      (Original File)<a name="line.72"></a>
-<span class="sourceLineNo">073</span> *  &lt;/li&gt;<a name="line.73"></a>
-<span class="sourceLineNo">074</span> *  &lt;li&gt;<a name="line.74"></a>
-<span class="sourceLineNo">075</span> *      /hbase/table-cloned/region-y/cf/file-k.region-x.table<a name="line.75"></a>
-<span class="sourceLineNo">076</span> *     (HFileLink to the original file)<a name="line.76"></a>
-<span class="sourceLineNo">077</span> *  &lt;/li&gt;<a name="line.77"></a>
-<span class="sourceLineNo">078</span> *  &lt;li&gt;<a name="line.78"></a>
-<span class="sourceLineNo">079</span> *      /hbase/table-2nd-cloned/region-z/cf/file-k.region-x.table<a name="line.79"></a>
-<span class="sourceLineNo">080</span> *      (HFileLink to the original file)<a name="line.80"></a>
-<span class="sourceLineNo">081</span> *  &lt;/li&gt;<a name="line.81"></a>
-<span class="sourceLineNo">082</span> *  &lt;li&gt;<a name="line.82"></a>
-<span class="sourceLineNo">083</span> *      /hbase/.archive/table/region-x/.links-file-k/region-y.table-cloned<a name="line.83"></a>
-<span class="sourceLineNo">084</span> *      (Back-reference to the link in table-cloned)<a name="line.84"></a>
-<span class="sourceLineNo">085</span> *  &lt;/li&gt;<a name="line.85"></a>
-<span class="sourceLineNo">086</span> *  &lt;li&gt;<a name="line.86"></a>
-<span class="sourceLineNo">087</span> *      /hbase/.archive/table/region-x/.links-file-k/region-z.table-2nd-cloned<a name="line.87"></a>
-<span class="sourceLineNo">088</span> *      (Back-reference to the link in table-2nd-cloned)<a name="line.88"></a>
-<span class="sourceLineNo">089</span> *  &lt;/li&gt;<a name="line.89"></a>
-<span class="sourceLineNo">090</span> * &lt;/ul&gt;<a name="line.90"></a>
-<span class="sourceLineNo">091</span> */<a name="line.91"></a>
-<span class="sourceLineNo">092</span>@InterfaceAudience.Private<a name="line.92"></a>
-<span class="sourceLineNo">093</span>public class FileLink {<a name="line.93"></a>
-<span class="sourceLineNo">094</span>  private static final Log LOG = LogFactory.getLog(FileLink.class);<a name="line.94"></a>
-<span class="sourceLineNo">095</span><a name="line.95"></a>
-<span class="sourceLineNo">096</span>  /** Define the Back-reference directory name prefix: .links-&amp;lt;hfile&amp;gt;/ */<a name="line.96"></a>
-<span class="sourceLineNo">097</span>  public static final String BACK_REFERENCES_DIRECTORY_PREFIX = ".links-";<a name="line.97"></a>
-<span class="sourceLineNo">098</span><a name="line.98"></a>
-<span class="sourceLineNo">099</span>  /**<a name="line.99"></a>
-<span class="sourceLineNo">100</span>   * FileLink InputStream that handles the switch between the original path<a name="line.100"></a>
-<span class="sourceLineNo">101</span>   * and the alternative locations, when the file is moved.<a name="line.101"></a>
-<span class="sourceLineNo">102</span>   */<a name="line.102"></a>
-<span class="sourceLineNo">103</span>  private static class FileLinkInputStream extends InputStream<a name="line.103"></a>
-<span class="sourceLineNo">104</span>      implements Seekable, PositionedReadable, CanSetDropBehind, CanSetReadahead {<a name="line.104"></a>
-<span class="sourceLineNo">105</span>    private FSDataInputStream in = null;<a name="line.105"></a>
-<span class="sourceLineNo">106</span>    private Path currentPath = null;<a name="line.106"></a>
-<span class="sourceLineNo">107</span>    private long pos = 0;<a name="line.107"></a>
-<span class="sourceLineNo">108</span><a name="line.108"></a>
-<span class="sourceLineNo">109</span>    private final FileLink fileLink;<a name="line.109"></a>
-<span class="sourceLineNo">110</span>    private final int bufferSize;<a name="line.110"></a>
-<span class="sourceLineNo">111</span>    private final FileSystem fs;<a name="line.111"></a>
-<span class="sourceLineNo">112</span><a name="line.112"></a>
-<span class="sourceLineNo">113</span>    public FileLinkInputStream(final FileSystem fs, final FileLink fileLink)<a name="line.113"></a>
-<span class="sourceLineNo">114</span>        throws IOException {<a name="line.114"></a>
-<span class="sourceLineNo">115</span>      this(fs, fileLink, FSUtils.getDefaultBufferSize(fs));<a name="line.115"></a>
-<span class="sourceLineNo">116</span>    }<a name="line.116"></a>
-<span class="sourceLineNo">117</span><a name="line.117"></a>
-<span class="sourceLineNo">118</span>    public FileLinkInputStream(final FileSystem fs, final FileLink fileLink, int bufferSize)<a name="line.118"></a>
-<span class="sourceLineNo">119</span>        throws IOException {<a name="line.119"></a>
-<span class="sourceLineNo">120</span>      this.bufferSize = bufferSize;<a name="line.120"></a>
-<span class="sourceLineNo">121</span>      this.fileLink = fileLink;<a name="line.121"></a>
-<span class="sourceLineNo">122</span>      this.fs = fs;<a name="line.122"></a>
-<span class="sourceLineNo">123</span><a name="line.123"></a>
-<span class="sourceLineNo">124</span>      this.in = tryOpen();<a name="line.124"></a>
-<span class="sourceLineNo">125</span>    }<a name="line.125"></a>
-<span class="sourceLineNo">126</span><a name="line.126"></a>
-<span class="sourceLineNo">127</span>    @Override<a name="line.127"></a>
-<span class="sourceLineNo">128</span>    public int read() throws IOException {<a name="line.128"></a>
-<span class="sourceLineNo">129</span>      int res;<a name="line.129"></a>
-<span class="sourceLineNo">130</span>      try {<a name="line.130"></a>
-<span class="sourceLineNo">131</span>        res = in.read();<a name="line.131"></a>
-<span class="sourceLineNo">132</span>      } catch (FileNotFoundException e) {<a name="line.132"></a>
-<span class="sourceLineNo">133</span>        res = tryOpen().read();<a name="line.133"></a>
-<span class="sourceLineNo">134</span>      } catch (NullPointerException e) { // HDFS 1.x - DFSInputStream.getBlockAt()<a name="line.134"></a>
-<span class="sourceLineNo">135</span>        res = tryOpen().read();<a name="line.135"></a>
-<span class="sourceLineNo">136</span>      } catch (AssertionError e) { // assert in HDFS 1.x - DFSInputStream.getBlockAt()<a name="line.136"></a>
-<span class="sourceLineNo">137</span>        res = tryOpen().read();<a name="line.137"></a>
-<span class="sourceLineNo">138</span>      }<a name="line.138"></a>
-<span class="sourceLineNo">139</span>      if (res &gt; 0) pos += 1;<a name="line.139"></a>
-<span class="sourceLineNo">140</span>      return res;<a name="line.140"></a>
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-<span class="sourceLineNo">144</span>    public int read(byte[] b) throws IOException {<a name="line.144"></a>
-<span class="sourceLineNo">145</span>       return read(b, 0, b.length);<a name="line.145"></a>
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-<span class="sourceLineNo">149</span>    public int read(byte[] b, int off, int len) throws IOException {<a name="line.149"></a>
-<span class="sourceLineNo">150</span>      int n;<a name="line.150"></a>
-<span class="sourceLineNo">151</span>      try {<a name="line.151"></a>
-<span class="sourceLineNo">152</span>        n = in.read(b, off, len);<a name="line.152"></a>
-<span class="sourceLineNo">153</span>      } catch (FileNotFoundException e) {<a name="line.153"></a>
-<span class="sourceLineNo">154</span>        n = tryOpen().read(b, off, len);<a name="line.154"></a>
-<span class="sourceLineNo">155</span>      } catch (NullPointerException e) { // HDFS 1.x - DFSInputStream.getBlockAt()<a name="line.155"></a>
-<span class="sourceLineNo">156</span>        n = tryOpen().read(b, off, len);<a name="line.156"></a>
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-<span class="sourceLineNo">158</span>        n = tryOpen().read(b, off, len);<a name="line.158"></a>
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-<span class="sourceLineNo">163</span>    }<a name="line.163"></a>
-<span class="sourceLineNo">164</span><a name="line.164"></a>
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-<span class="sourceLineNo">167</span>      int n;<a name="line.167"></a>
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-<span class="sourceLineNo">192</span>        tryOpen().readFully(position, buffer, offset, length);<a name="line.192"></a>
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-<span class="sourceLineNo">194</span>        tryOpen().readFully(position, buffer, offset, length);<a name="line.194"></a>
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-<span class="sourceLineNo">200</span>      long skipped;<a name="line.200"></a>
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-<span class="sourceLineNo">236</span>        tryOpen().seek(pos);<a name="line.236"></a>
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+<span class="sourceLineNo">366</span><a name="line.366"></a>
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+<span class="sourceLineNo">378</span><a name="line.378"></a>
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+<span class="sourceLineNo">381</span>   */<a name="line.381"></a>
+<span class="sourceLineNo">382</span>  public Path getAvailablePath(FileSystem fs) throws IOException {<a name="line.382"></a>
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+<span class="sourceLineNo">390</span><a name="line.390"></a>
+<span class="sourceLineNo">391</span>  /**<a name="line.391"></a>
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+<span class="sourceLineNo">394</span>   * @param fs {@link FileSystem} on which to get the file status<a name="line.394"></a>
+<span class="sourceLineNo">395</span>   * @return InputStream for the hfile link.<a name="line.395"></a>
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+<span class="sourceLineNo">408</span><a name="line.408"></a>
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+<span class="sourceLineNo">422</span><a name="line.422"></a>
+<span class="sourceLineNo">423</span>  /**<a name="line.423"></a>
+<span class="sourceLineNo">424</span>   * Open the FileLink for read.<a name="line.424"></a>
+<span class="sourceLineNo">425</span>   * &lt;p&gt;<a name="line.425"></a>
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+<span class="sourceLineNo">427</span>   * of the file, even if the file switches between locations.<a name="line.427"></a>
+<span class="sourceLineNo">428</span>   *<a name="line.428"></a>
+<span class="sourceLineNo">429</span>   * @param fs {@link FileSystem} on which to open the FileLink<a name="line.429"></a>
+<span class="sourceLineNo">430</span>   * @param bufferSize the size of the buffer to be used.<a name="line.430"></a>
+<span class="sourceLineNo">431</span>   * @return InputStream for reading the file link.<a name="line.431"></a>
+<span class="sourceLineNo">432</span>   * @throws IOException on unexpected error.<a name="line.432"></a>
+<span class="sourceLineNo">433</span>   */<a name="line.433"></a>
+<span class="sourceLineNo">434</span>  public FSDataInputStream open(final FileSystem fs, int bufferSize) throws IOException {<a name="line.434"></a>
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+<span class="sourceLineNo">437</span><a name="line.437"></a>
+<span class="sourceLineNo">438</span>  /**<a name="line.438"></a>
+<span class="sourceLineNo">439</span>   * NOTE: This method must be used only in the constructor!<a name="line.439"></a>
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+<span class="sourceLineNo">441</span>   */<a name="line.441"></a>
+<span class="sourceLineNo">442</span>  protected void setLocations(Path originPath, Path... alternativePaths) {<a name="line.442"></a>
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+<span class="sourceLineNo">444</span><a name="line.444"></a>
+<span class="sourceLineNo">445</span>    List&lt;Path&gt; paths = new ArrayList&lt;&gt;(alternativePaths.length +1);<a name="line.445"></a>
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+<span class="sourceLineNo">454</span>    }<a name="line.454"></a>
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+<span class="sourceLineNo">457</span><a name="line.457"></a>
+<span class="sourceLineNo">458</span>  /**<a name="line.458"></a>
+<span class="sourceLineNo">459</span>   * Get the directory to store the link back references<a name="line.459"></a>
+<span class="sourceLineNo">460</span>   *<a name="line.460"></a>
+<span class="sourceLineNo">461</span>   * &lt;p&gt;To simplify the reference count process, during the FileLink creation<a name="line.461"></a>
+<span class="sourceLineNo">462</span>   * a back-reference is added to the back-reference directory of the specified file.<a name="line.462"></a>
+<span class="sourceLineNo">463</span>   *<a name="line.463"></a>
+<span class="sourceLineNo">464</span>   * @param storeDir Root directory for the link reference folder<a name="line.464"></a>
+<span class="sourceLineNo">465</span>   * @param fileName File Name with links<a name="line.465"></a>
+<span class="sourceLineNo">466</span>   * @return Path for the link back references.<a name="line.466"></a>
+<span class="sourceLineNo">467</span>   */<a name="line.467"></a>
+<span class="sourceLineNo">468</span>  public static Path getBackReferencesDir(final Path storeDir, final String fileName) {<a name="line.468"></a>
+<span class="sourceLineNo">469</span>    return new Path(storeDir, BACK_REFERENCES_DIRECTORY_PREFIX + fileName);<a name="line.469"></a>
+<span class="sourceLineNo">470</span>  }<a name="line.470"></a>
+<span class="sourceLineNo">471</span><a name="line.471"></a>
+<span class="sourceLineNo">472</span>  /**<a name="line.472"></a>
+<span class="sourceLineNo">473</span>   * Get the referenced file name from the reference link directory path.<a name="line.473"></a>
+<span class="sourceLineNo">474</span>   *<a name="line.474"></a>
+<span class="sourceLineNo">475</span>   * @param dirPath Link references directory path<a name="line.475"></a>
+<span class="sourceLineNo">476</span>   * @return Name of the file referenced<a name="line.476"></a>
+<span class="sourceLineNo">477</span>   */<a name="line.477"></a>
+<span class="sourceLineNo">478</span>  public static String getBackReferenceFileName(final Path dirPath) {<a name="line.478"></a>
+<span class="sourceLineNo">479</span>    return dirPath.getName().substring(BACK_REFERENCES_DIRECTORY_PREFIX.length());<a name="line.479"></a>
+<span class="sourceLineNo">480</span>  }<a name="line.480"></a>
+<span class="sourceLineNo">481</span><a name="line.481"></a>
+<span class="sourceLineNo">482</span>  /**<a name="line.482"></a>
+<span class="sourceLineNo">483</span>   * Checks if the specified directory path is a back reference links folder.<a name="line.483"></a>
+<span class="sourceLineNo">484</span>   *<a name="line.484"></a>
+<span class="sourceLineNo">485</span>   * @param dirPath Directory path to verify<a name="line.485"></a>
+<span class="sourceLineNo">486</span>   * @return True if the specified directory is a link references folder<a name="line.486"></a>
+<span class="sourceLineNo">487</span>   */<a name="line.487"></a>
+<span class="sourceLineNo">488</span>  public static boolean isBackReferencesDir(final Path dirPath) {<a name="line.488"></a>
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+<span class="sourceLineNo">492</span><a name="line.492"></a>
+<span class="sourceLineNo">493</span>  @Override<a name="line.493"></a>
+<span class="sourceLineNo">494</span>  public boolean equals(Object obj) {<a name="line.494"></a>
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+<span class="sourceLineNo">497</span>    }<a name="line.497"></a>
+<span class="sourceLineNo">498</span>    // Assumes that the ordering of locations between objects are the same. This is true for the<a name="line.498"></a>
+<span class="sourceLineNo">499</span>    // current subclasses already (HFileLink, WALLink). Otherwise, we may have to sort the locations<a name="line.499"></a>
+<span class="sourceLineNo">500</span>    // or keep them presorted<a name="line.500"></a>
+<span class="sourceLineNo">501</span>    if (this.getClass().equals(obj.getClass())) {<a name="line.501"></a>
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+<span class="sourceLineNo">503</span>    }<a name="line.503"></a>
+<span class="sourceLineNo">504</span><a name="line.504"></a>
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+<span class="sourceLineNo">507</span><a name="line.507"></a>
+<span class="sourceLineNo">508</span>  @Override<a name="line.508"></a>
+<span class="sourceLineNo">509</span>  public int hashCode() {<a name="line.509"></a>
+<span class="sourceLineNo">510</span>    return Arrays.hashCode(locations);<a name="line.510"></a>
+<span class="sourceLineNo">511</span>  }<a name="line.511"></a>
+<span class="sourceLineNo">512</span>}<a name="line.512"></a>
+<span class="sourceLineNo">513</span><a name="line.513"></a>
 
 
 


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