http://git-wip-us.apache.org/repos/asf/hbase-site/blob/1241ee85/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/KeyValueHeap.html
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diff --git
a/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/KeyValueHeap.html
b/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/KeyValueHeap.html
index d84c4f8..a4fc8e5 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/KeyValueHeap.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/regionserver/KeyValueHeap.html
@@ -27,435 +27,438 @@
<span class="sourceLineNo">019</span><a name="line.19"></a>
<span class="sourceLineNo">020</span>package
org.apache.hadoop.hbase.regionserver;<a name="line.20"></a>
<span class="sourceLineNo">021</span><a name="line.21"></a>
-<span class="sourceLineNo">022</span>import java.io.IOException;<a
name="line.22"></a>
-<span class="sourceLineNo">023</span>import java.util.ArrayList;<a
name="line.23"></a>
-<span class="sourceLineNo">024</span>import java.util.Comparator;<a
name="line.24"></a>
-<span class="sourceLineNo">025</span>import java.util.List;<a
name="line.25"></a>
-<span class="sourceLineNo">026</span>import java.util.PriorityQueue;<a
name="line.26"></a>
-<span class="sourceLineNo">027</span><a name="line.27"></a>
-<span class="sourceLineNo">028</span>import org.apache.commons.logging.Log;<a
name="line.28"></a>
-<span class="sourceLineNo">029</span>import
org.apache.commons.logging.LogFactory;<a name="line.29"></a>
-<span class="sourceLineNo">030</span>import org.apache.hadoop.hbase.Cell;<a
name="line.30"></a>
-<span class="sourceLineNo">031</span>import
org.apache.hadoop.hbase.CellComparator;<a name="line.31"></a>
-<span class="sourceLineNo">032</span>import
org.apache.hadoop.hbase.classification.InterfaceAudience;<a name="line.32"></a>
-<span class="sourceLineNo">033</span>import
org.apache.hadoop.hbase.regionserver.ScannerContext.NextState;<a
name="line.33"></a>
-<span class="sourceLineNo">034</span><a name="line.34"></a>
-<span class="sourceLineNo">035</span>/**<a name="line.35"></a>
-<span class="sourceLineNo">036</span> * Implements a heap merge across any
number of KeyValueScanners.<a name="line.36"></a>
-<span class="sourceLineNo">037</span> * <p><a name="line.37"></a>
-<span class="sourceLineNo">038</span> * Implements KeyValueScanner itself.<a
name="line.38"></a>
+<span class="sourceLineNo">022</span>import
com.google.common.annotations.VisibleForTesting;<a name="line.22"></a>
+<span class="sourceLineNo">023</span><a name="line.23"></a>
+<span class="sourceLineNo">024</span>import java.io.IOException;<a
name="line.24"></a>
+<span class="sourceLineNo">025</span>import java.util.ArrayList;<a
name="line.25"></a>
+<span class="sourceLineNo">026</span>import java.util.Comparator;<a
name="line.26"></a>
+<span class="sourceLineNo">027</span>import java.util.List;<a
name="line.27"></a>
+<span class="sourceLineNo">028</span>import java.util.PriorityQueue;<a
name="line.28"></a>
+<span class="sourceLineNo">029</span><a name="line.29"></a>
+<span class="sourceLineNo">030</span>import org.apache.commons.logging.Log;<a
name="line.30"></a>
+<span class="sourceLineNo">031</span>import
org.apache.commons.logging.LogFactory;<a name="line.31"></a>
+<span class="sourceLineNo">032</span>import org.apache.hadoop.hbase.Cell;<a
name="line.32"></a>
+<span class="sourceLineNo">033</span>import
org.apache.hadoop.hbase.CellComparator;<a name="line.33"></a>
+<span class="sourceLineNo">034</span>import
org.apache.hadoop.hbase.classification.InterfaceAudience;<a name="line.34"></a>
+<span class="sourceLineNo">035</span>import
org.apache.hadoop.hbase.regionserver.ScannerContext.NextState;<a
name="line.35"></a>
+<span class="sourceLineNo">036</span><a name="line.36"></a>
+<span class="sourceLineNo">037</span>/**<a name="line.37"></a>
+<span class="sourceLineNo">038</span> * Implements a heap merge across any
number of KeyValueScanners.<a name="line.38"></a>
<span class="sourceLineNo">039</span> * <p><a name="line.39"></a>
-<span class="sourceLineNo">040</span> * This class is used at the Region level
to merge across Stores<a name="line.40"></a>
-<span class="sourceLineNo">041</span> * and at the Store level to merge across
the memstore and StoreFiles.<a name="line.41"></a>
-<span class="sourceLineNo">042</span> * <p><a name="line.42"></a>
-<span class="sourceLineNo">043</span> * In the Region case, we also need
InternalScanner.next(List), so this class<a name="line.43"></a>
-<span class="sourceLineNo">044</span> * also implements InternalScanner.
WARNING: As is, if you try to use this<a name="line.44"></a>
-<span class="sourceLineNo">045</span> * as an InternalScanner at the Store
level, you will get runtime exceptions.<a name="line.45"></a>
-<span class="sourceLineNo">046</span> */<a name="line.46"></a>
-<span class="sourceLineNo">047</span>@InterfaceAudience.Private<a
name="line.47"></a>
-<span class="sourceLineNo">048</span>public class KeyValueHeap extends
NonReversedNonLazyKeyValueScanner<a name="line.48"></a>
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InternalScanner {<a name="line.49"></a>
-<span class="sourceLineNo">050</span> private static final Log LOG =
LogFactory.getLog(KeyValueHeap.class);<a name="line.50"></a>
-<span class="sourceLineNo">051</span> protected
PriorityQueue<KeyValueScanner> heap = null;<a name="line.51"></a>
-<span class="sourceLineNo">052</span> // Holds the scanners when a ever a
eager close() happens. All such eagerly closed<a name="line.52"></a>
-<span class="sourceLineNo">053</span> // scans are collected and when the
final scanner.close() happens will perform the<a name="line.53"></a>
-<span class="sourceLineNo">054</span> // actual close.<a name="line.54"></a>
-<span class="sourceLineNo">055</span> protected List<KeyValueScanner>
scannersForDelayedClose = null;<a name="line.55"></a>
-<span class="sourceLineNo">056</span><a name="line.56"></a>
-<span class="sourceLineNo">057</span> /**<a name="line.57"></a>
-<span class="sourceLineNo">058</span> * The current sub-scanner, i.e. the
one that contains the next key/value<a name="line.58"></a>
-<span class="sourceLineNo">059</span> * to return to the client. This
scanner is NOT included in {@link #heap}<a name="line.59"></a>
-<span class="sourceLineNo">060</span> * (but we frequently add it back to
the heap and pull the new winner out).<a name="line.60"></a>
-<span class="sourceLineNo">061</span> * We maintain an invariant that the
current sub-scanner has already done<a name="line.61"></a>
-<span class="sourceLineNo">062</span> * a real seek, and that current.peek()
is always a real key/value (or null)<a name="line.62"></a>
-<span class="sourceLineNo">063</span> * except for the fake
last-key-on-row-column supplied by the multi-column<a name="line.63"></a>
-<span class="sourceLineNo">064</span> * Bloom filter optimization, which is
OK to propagate to StoreScanner. In<a name="line.64"></a>
-<span class="sourceLineNo">065</span> * order to ensure that, always use
{@link #pollRealKV()} to update current.<a name="line.65"></a>
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-<span class="sourceLineNo">067</span> protected KeyValueScanner current =
null;<a name="line.67"></a>
-<span class="sourceLineNo">068</span><a name="line.68"></a>
-<span class="sourceLineNo">069</span> protected KVScannerComparator
comparator;<a name="line.69"></a>
+<span class="sourceLineNo">040</span> * Implements KeyValueScanner itself.<a
name="line.40"></a>
+<span class="sourceLineNo">041</span> * <p><a name="line.41"></a>
+<span class="sourceLineNo">042</span> * This class is used at the Region level
to merge across Stores<a name="line.42"></a>
+<span class="sourceLineNo">043</span> * and at the Store level to merge across
the memstore and StoreFiles.<a name="line.43"></a>
+<span class="sourceLineNo">044</span> * <p><a name="line.44"></a>
+<span class="sourceLineNo">045</span> * In the Region case, we also need
InternalScanner.next(List), so this class<a name="line.45"></a>
+<span class="sourceLineNo">046</span> * also implements InternalScanner.
WARNING: As is, if you try to use this<a name="line.46"></a>
+<span class="sourceLineNo">047</span> * as an InternalScanner at the Store
level, you will get runtime exceptions.<a name="line.47"></a>
+<span class="sourceLineNo">048</span> */<a name="line.48"></a>
+<span class="sourceLineNo">049</span>@InterfaceAudience.Private<a
name="line.49"></a>
+<span class="sourceLineNo">050</span>public class KeyValueHeap extends
NonReversedNonLazyKeyValueScanner<a name="line.50"></a>
+<span class="sourceLineNo">051</span> implements KeyValueScanner,
InternalScanner {<a name="line.51"></a>
+<span class="sourceLineNo">052</span> private static final Log LOG =
LogFactory.getLog(KeyValueHeap.class);<a name="line.52"></a>
+<span class="sourceLineNo">053</span> protected
PriorityQueue<KeyValueScanner> heap = null;<a name="line.53"></a>
+<span class="sourceLineNo">054</span> // Holds the scanners when a ever a
eager close() happens. All such eagerly closed<a name="line.54"></a>
+<span class="sourceLineNo">055</span> // scans are collected and when the
final scanner.close() happens will perform the<a name="line.55"></a>
+<span class="sourceLineNo">056</span> // actual close.<a name="line.56"></a>
+<span class="sourceLineNo">057</span> protected List<KeyValueScanner>
scannersForDelayedClose = null;<a name="line.57"></a>
+<span class="sourceLineNo">058</span><a name="line.58"></a>
+<span class="sourceLineNo">059</span> /**<a name="line.59"></a>
+<span class="sourceLineNo">060</span> * The current sub-scanner, i.e. the
one that contains the next key/value<a name="line.60"></a>
+<span class="sourceLineNo">061</span> * to return to the client. This
scanner is NOT included in {@link #heap}<a name="line.61"></a>
+<span class="sourceLineNo">062</span> * (but we frequently add it back to
the heap and pull the new winner out).<a name="line.62"></a>
+<span class="sourceLineNo">063</span> * We maintain an invariant that the
current sub-scanner has already done<a name="line.63"></a>
+<span class="sourceLineNo">064</span> * a real seek, and that current.peek()
is always a real key/value (or null)<a name="line.64"></a>
+<span class="sourceLineNo">065</span> * except for the fake
last-key-on-row-column supplied by the multi-column<a name="line.65"></a>
+<span class="sourceLineNo">066</span> * Bloom filter optimization, which is
OK to propagate to StoreScanner. In<a name="line.66"></a>
+<span class="sourceLineNo">067</span> * order to ensure that, always use
{@link #pollRealKV()} to update current.<a name="line.67"></a>
+<span class="sourceLineNo">068</span> */<a name="line.68"></a>
+<span class="sourceLineNo">069</span> protected KeyValueScanner current =
null;<a name="line.69"></a>
<span class="sourceLineNo">070</span><a name="line.70"></a>
-<span class="sourceLineNo">071</span> /**<a name="line.71"></a>
-<span class="sourceLineNo">072</span> * Constructor. This KeyValueHeap will
handle closing of passed in<a name="line.72"></a>
-<span class="sourceLineNo">073</span> * KeyValueScanners.<a
name="line.73"></a>
-<span class="sourceLineNo">074</span> * @param scanners<a name="line.74"></a>
-<span class="sourceLineNo">075</span> * @param comparator<a
name="line.75"></a>
-<span class="sourceLineNo">076</span> */<a name="line.76"></a>
-<span class="sourceLineNo">077</span> public KeyValueHeap(List<? extends
KeyValueScanner> scanners,<a name="line.77"></a>
-<span class="sourceLineNo">078</span> CellComparator comparator) throws
IOException {<a name="line.78"></a>
-<span class="sourceLineNo">079</span> this(scanners, new
KVScannerComparator(comparator));<a name="line.79"></a>
-<span class="sourceLineNo">080</span> }<a name="line.80"></a>
-<span class="sourceLineNo">081</span><a name="line.81"></a>
-<span class="sourceLineNo">082</span> /**<a name="line.82"></a>
-<span class="sourceLineNo">083</span> * Constructor.<a name="line.83"></a>
-<span class="sourceLineNo">084</span> * @param scanners<a name="line.84"></a>
-<span class="sourceLineNo">085</span> * @param comparator<a
name="line.85"></a>
-<span class="sourceLineNo">086</span> * @throws IOException<a
name="line.86"></a>
-<span class="sourceLineNo">087</span> */<a name="line.87"></a>
-<span class="sourceLineNo">088</span> KeyValueHeap(List<? extends
KeyValueScanner> scanners,<a name="line.88"></a>
-<span class="sourceLineNo">089</span> KVScannerComparator comparator)
throws IOException {<a name="line.89"></a>
-<span class="sourceLineNo">090</span> this.comparator = comparator;<a
name="line.90"></a>
-<span class="sourceLineNo">091</span> this.scannersForDelayedClose = new
ArrayList<>(scanners.size());<a name="line.91"></a>
-<span class="sourceLineNo">092</span> if (!scanners.isEmpty()) {<a
name="line.92"></a>
-<span class="sourceLineNo">093</span> this.heap = new
PriorityQueue<>(scanners.size(), this.comparator);<a name="line.93"></a>
-<span class="sourceLineNo">094</span> for (KeyValueScanner scanner :
scanners) {<a name="line.94"></a>
-<span class="sourceLineNo">095</span> if (scanner.peek() != null) {<a
name="line.95"></a>
-<span class="sourceLineNo">096</span> this.heap.add(scanner);<a
name="line.96"></a>
-<span class="sourceLineNo">097</span> } else {<a name="line.97"></a>
-<span class="sourceLineNo">098</span>
this.scannersForDelayedClose.add(scanner);<a name="line.98"></a>
-<span class="sourceLineNo">099</span> }<a name="line.99"></a>
-<span class="sourceLineNo">100</span> }<a name="line.100"></a>
-<span class="sourceLineNo">101</span> this.current = pollRealKV();<a
name="line.101"></a>
-<span class="sourceLineNo">102</span> }<a name="line.102"></a>
-<span class="sourceLineNo">103</span> }<a name="line.103"></a>
-<span class="sourceLineNo">104</span><a name="line.104"></a>
-<span class="sourceLineNo">105</span> public Cell peek() {<a
name="line.105"></a>
-<span class="sourceLineNo">106</span> if (this.current == null) {<a
name="line.106"></a>
-<span class="sourceLineNo">107</span> return null;<a name="line.107"></a>
-<span class="sourceLineNo">108</span> }<a name="line.108"></a>
-<span class="sourceLineNo">109</span> return this.current.peek();<a
name="line.109"></a>
-<span class="sourceLineNo">110</span> }<a name="line.110"></a>
-<span class="sourceLineNo">111</span><a name="line.111"></a>
-<span class="sourceLineNo">112</span> public Cell next() throws IOException
{<a name="line.112"></a>
-<span class="sourceLineNo">113</span> if(this.current == null) {<a
name="line.113"></a>
-<span class="sourceLineNo">114</span> return null;<a name="line.114"></a>
-<span class="sourceLineNo">115</span> }<a name="line.115"></a>
-<span class="sourceLineNo">116</span> Cell kvReturn =
this.current.next();<a name="line.116"></a>
-<span class="sourceLineNo">117</span> Cell kvNext = this.current.peek();<a
name="line.117"></a>
-<span class="sourceLineNo">118</span> if (kvNext == null) {<a
name="line.118"></a>
-<span class="sourceLineNo">119</span>
this.scannersForDelayedClose.add(this.current);<a name="line.119"></a>
-<span class="sourceLineNo">120</span> this.current = null;<a
name="line.120"></a>
-<span class="sourceLineNo">121</span> this.current = pollRealKV();<a
name="line.121"></a>
-<span class="sourceLineNo">122</span> } else {<a name="line.122"></a>
-<span class="sourceLineNo">123</span> KeyValueScanner topScanner =
this.heap.peek();<a name="line.123"></a>
-<span class="sourceLineNo">124</span> // no need to add current back to
the heap if it is the only scanner left<a name="line.124"></a>
-<span class="sourceLineNo">125</span> if (topScanner != null &&
this.comparator.compare(kvNext, topScanner.peek()) >= 0) {<a
name="line.125"></a>
-<span class="sourceLineNo">126</span> this.heap.add(this.current);<a
name="line.126"></a>
-<span class="sourceLineNo">127</span> this.current = null;<a
name="line.127"></a>
-<span class="sourceLineNo">128</span> this.current = pollRealKV();<a
name="line.128"></a>
-<span class="sourceLineNo">129</span> }<a name="line.129"></a>
-<span class="sourceLineNo">130</span> }<a name="line.130"></a>
-<span class="sourceLineNo">131</span> return kvReturn;<a
name="line.131"></a>
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-<span class="sourceLineNo">134</span> /**<a name="line.134"></a>
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top-most scanner.<a name="line.135"></a>
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-<span class="sourceLineNo">137</span> * This method takes care of updating
the heap.<a name="line.137"></a>
+<span class="sourceLineNo">071</span> protected KVScannerComparator
comparator;<a name="line.71"></a>
+<span class="sourceLineNo">072</span><a name="line.72"></a>
+<span class="sourceLineNo">073</span> /**<a name="line.73"></a>
+<span class="sourceLineNo">074</span> * Constructor. This KeyValueHeap will
handle closing of passed in<a name="line.74"></a>
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name="line.75"></a>
+<span class="sourceLineNo">076</span> * @param scanners<a name="line.76"></a>
+<span class="sourceLineNo">077</span> * @param comparator<a
name="line.77"></a>
+<span class="sourceLineNo">078</span> */<a name="line.78"></a>
+<span class="sourceLineNo">079</span> public KeyValueHeap(List<? extends
KeyValueScanner> scanners,<a name="line.79"></a>
+<span class="sourceLineNo">080</span> CellComparator comparator) throws
IOException {<a name="line.80"></a>
+<span class="sourceLineNo">081</span> this(scanners, new
KVScannerComparator(comparator));<a name="line.81"></a>
+<span class="sourceLineNo">082</span> }<a name="line.82"></a>
+<span class="sourceLineNo">083</span><a name="line.83"></a>
+<span class="sourceLineNo">084</span> /**<a name="line.84"></a>
+<span class="sourceLineNo">085</span> * Constructor.<a name="line.85"></a>
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+<span class="sourceLineNo">087</span> * @param comparator<a
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+<span class="sourceLineNo">088</span> * @throws IOException<a
name="line.88"></a>
+<span class="sourceLineNo">089</span> */<a name="line.89"></a>
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KeyValueScanner> scanners,<a name="line.90"></a>
+<span class="sourceLineNo">091</span> KVScannerComparator comparator)
throws IOException {<a name="line.91"></a>
+<span class="sourceLineNo">092</span> this.comparator = comparator;<a
name="line.92"></a>
+<span class="sourceLineNo">093</span> this.scannersForDelayedClose = new
ArrayList<>(scanners.size());<a name="line.93"></a>
+<span class="sourceLineNo">094</span> if (!scanners.isEmpty()) {<a
name="line.94"></a>
+<span class="sourceLineNo">095</span> this.heap = new
PriorityQueue<>(scanners.size(), this.comparator);<a name="line.95"></a>
+<span class="sourceLineNo">096</span> for (KeyValueScanner scanner :
scanners) {<a name="line.96"></a>
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name="line.97"></a>
+<span class="sourceLineNo">098</span> this.heap.add(scanner);<a
name="line.98"></a>
+<span class="sourceLineNo">099</span> } else {<a name="line.99"></a>
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this.scannersForDelayedClose.add(scanner);<a name="line.100"></a>
+<span class="sourceLineNo">101</span> }<a name="line.101"></a>
+<span class="sourceLineNo">102</span> }<a name="line.102"></a>
+<span class="sourceLineNo">103</span> this.current = pollRealKV();<a
name="line.103"></a>
+<span class="sourceLineNo">104</span> }<a name="line.104"></a>
+<span class="sourceLineNo">105</span> }<a name="line.105"></a>
+<span class="sourceLineNo">106</span><a name="line.106"></a>
+<span class="sourceLineNo">107</span> public Cell peek() {<a
name="line.107"></a>
+<span class="sourceLineNo">108</span> if (this.current == null) {<a
name="line.108"></a>
+<span class="sourceLineNo">109</span> return null;<a name="line.109"></a>
+<span class="sourceLineNo">110</span> }<a name="line.110"></a>
+<span class="sourceLineNo">111</span> return this.current.peek();<a
name="line.111"></a>
+<span class="sourceLineNo">112</span> }<a name="line.112"></a>
+<span class="sourceLineNo">113</span><a name="line.113"></a>
+<span class="sourceLineNo">114</span> public Cell next() throws IOException
{<a name="line.114"></a>
+<span class="sourceLineNo">115</span> if(this.current == null) {<a
name="line.115"></a>
+<span class="sourceLineNo">116</span> return null;<a name="line.116"></a>
+<span class="sourceLineNo">117</span> }<a name="line.117"></a>
+<span class="sourceLineNo">118</span> Cell kvReturn =
this.current.next();<a name="line.118"></a>
+<span class="sourceLineNo">119</span> Cell kvNext = this.current.peek();<a
name="line.119"></a>
+<span class="sourceLineNo">120</span> if (kvNext == null) {<a
name="line.120"></a>
+<span class="sourceLineNo">121</span>
this.scannersForDelayedClose.add(this.current);<a name="line.121"></a>
+<span class="sourceLineNo">122</span> this.current = null;<a
name="line.122"></a>
+<span class="sourceLineNo">123</span> this.current = pollRealKV();<a
name="line.123"></a>
+<span class="sourceLineNo">124</span> } else {<a name="line.124"></a>
+<span class="sourceLineNo">125</span> KeyValueScanner topScanner =
this.heap.peek();<a name="line.125"></a>
+<span class="sourceLineNo">126</span> // no need to add current back to
the heap if it is the only scanner left<a name="line.126"></a>
+<span class="sourceLineNo">127</span> if (topScanner != null &&
this.comparator.compare(kvNext, topScanner.peek()) >= 0) {<a
name="line.127"></a>
+<span class="sourceLineNo">128</span> this.heap.add(this.current);<a
name="line.128"></a>
+<span class="sourceLineNo">129</span> this.current = null;<a
name="line.129"></a>
+<span class="sourceLineNo">130</span> this.current = pollRealKV();<a
name="line.130"></a>
+<span class="sourceLineNo">131</span> }<a name="line.131"></a>
+<span class="sourceLineNo">132</span> }<a name="line.132"></a>
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for certain optimizations.<a name="line.165"></a>
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name="line.186"></a>
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name="line.199"></a>
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most-recent-file-first optimizations for<a name="line.281"></a>
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forward (also known as reseek)<a name="line.284"></a>
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Seek KeyValue. We only know that all<a name="line.303"></a>
+<span class="sourceLineNo">304</span> // scanners are at or after
seekKey (because fake keys of<a name="line.304"></a>
+<span class="sourceLineNo">305</span> // scanners where a lazy-seek
operation has been done are not greater<a name="line.305"></a>
+<span class="sourceLineNo">306</span> // than their real next keys)
but we still need to enforce our<a name="line.306"></a>
+<span class="sourceLineNo">307</span> // invariant that the top
scanner has done a real seek. This way<a name="line.307"></a>
+<span class="sourceLineNo">308</span> // StoreScanner and
RegionScanner do not have to worry about fake<a name="line.308"></a>
+<span class="sourceLineNo">309</span> // keys.<a name="line.309"></a>
+<span class="sourceLineNo">310</span> heap.add(scanner);<a
name="line.310"></a>
+<span class="sourceLineNo">311</span> scanner = null;<a
name="line.311"></a>
+<span class="sourceLineNo">312</span> current = pollRealKV();<a
name="line.312"></a>
+<span class="sourceLineNo">313</span> return current != null;<a
name="line.313"></a>
+<span class="sourceLineNo">314</span> }<a name="line.314"></a>
+<span class="sourceLineNo">315</span><a name="line.315"></a>
+<span class="sourceLineNo">316</span> boolean seekResult;<a
name="line.316"></a>
+<span class="sourceLineNo">317</span> if (isLazy && heap.size()
> 0) {<a name="line.317"></a>
+<span class="sourceLineNo">318</span> // If there is only one scanner
left, we don't do lazy seek.<a name="line.318"></a>
+<span class="sourceLineNo">319</span> seekResult =
scanner.requestSeek(seekKey, forward, useBloom);<a name="line.319"></a>
+<span class="sourceLineNo">320</span> } else {<a name="line.320"></a>
+<span class="sourceLineNo">321</span> seekResult =
NonLazyKeyValueScanner.doRealSeek(scanner, seekKey,<a name="line.321"></a>
+<span class="sourceLineNo">322</span> forward);<a
name="line.322"></a>
+<span class="sourceLineNo">323</span> }<a name="line.323"></a>
+<span class="sourceLineNo">324</span><a name="line.324"></a>
+<span class="sourceLineNo">325</span> if (!seekResult) {<a
name="line.325"></a>
+<span class="sourceLineNo">326</span>
this.scannersForDelayedClose.add(scanner);<a name="line.326"></a>
+<span class="sourceLineNo">327</span> } else {<a name="line.327"></a>
+<span class="sourceLineNo">328</span> heap.add(scanner);<a
name="line.328"></a>
+<span class="sourceLineNo">329</span> }<a name="line.329"></a>
+<span class="sourceLineNo">330</span> scanner = heap.poll();<a
name="line.330"></a>
+<span class="sourceLineNo">331</span> if (scanner == null) {<a
name="line.331"></a>
+<span class="sourceLineNo">332</span> current = null;<a
name="line.332"></a>
+<span class="sourceLineNo">333</span> }<a name="line.333"></a>
+<span class="sourceLineNo">334</span> }<a name="line.334"></a>
+<span class="sourceLineNo">335</span> } catch (Exception e) {<a
name="line.335"></a>
+<span class="sourceLineNo">336</span> if (scanner != null) {<a
name="line.336"></a>
+<span class="sourceLineNo">337</span> try {<a name="line.337"></a>
+<span class="sourceLineNo">338</span> scanner.close();<a
name="line.338"></a>
+<span class="sourceLineNo">339</span> } catch (Exception ce) {<a
name="line.339"></a>
+<span class="sourceLineNo">340</span> LOG.warn("close KeyValueScanner
error", ce);<a name="line.340"></a>
+<span class="sourceLineNo">341</span> }<a name="line.341"></a>
+<span class="sourceLineNo">342</span> }<a name="line.342"></a>
+<span class="sourceLineNo">343</span> throw e;<a name="line.343"></a>
+<span class="sourceLineNo">344</span> }<a name="line.344"></a>
+<span class="sourceLineNo">345</span><a name="line.345"></a>
+<span class="sourceLineNo">346</span> // Heap is returning empty, scanner
is done<a name="line.346"></a>
+<span class="sourceLineNo">347</span> return false;<a name="line.347"></a>
+<span class="sourceLineNo">348</span> }<a name="line.348"></a>
+<span class="sourceLineNo">349</span><a name="line.349"></a>
+<span class="sourceLineNo">350</span> /**<a name="line.350"></a>
+<span class="sourceLineNo">351</span> * Fetches the top sub-scanner from the
priority queue, ensuring that a real<a name="line.351"></a>
+<span class="sourceLineNo">352</span> * seek has been done on it. Works by
fetching the top sub-scanner, and if it<a name="line.352"></a>
+<span class="sourceLineNo">353</span> * has not done a real seek, making it
do so (which will modify its top KV),<a name="line.353"></a>
+<span class="sourceLineNo">354</span> * putting it back, and repeating this
until success. Relies on the fact that<a name="line.354"></a>
+<span class="sourceLineNo">355</span> * on a lazy seek we set the current
key of a StoreFileScanner to a KV that<a name="line.355"></a>
+<span class="sourceLineNo">356</span> * is not greater than the real next KV
to be read from that file, so the<a name="line.356"></a>
+<span class="sourceLineNo">357</span> * scanner that bubbles up to the top
of the heap will have global next KV in<a name="line.357"></a>
+<span class="sourceLineNo">358</span> * this scanner heap if (1) it has done
a real seek and (2) its KV is the top<a name="line.358"></a>
+<span class="sourceLineNo">359</span> * among all top KVs (some of which are
fake) in the scanner heap.<a name="line.359"></a>
+<span class="sourceLineNo">360</span> */<a name="line.360"></a>
+<span class="sourceLineNo">361</span> protected KeyValueScanner pollRealKV()
throws IOException {<a name="line.361"></a>
+<span class="sourceLineNo">362</span> KeyValueScanner kvScanner =
heap.poll();<a name="line.362"></a>
+<span class="sourceLineNo">363</span> if (kvScanner == null) {<a
name="line.363"></a>
+<span class="sourceLineNo">364</span> return null;<a name="line.364"></a>
+<span class="sourceLineNo">365</span> }<a name="line.365"></a>
+<span class="sourceLineNo">366</span><a name="line.366"></a>
+<span class="sourceLineNo">367</span> while (kvScanner != null &&
!kvScanner.realSeekDone()) {<a name="line.367"></a>
+<span class="sourceLineNo">368</span> if (kvScanner.peek() != null) {<a
name="line.368"></a>
+<span class="sourceLineNo">369</span> try {<a name="line.369"></a>
+<span class="sourceLineNo">370</span> kvScanner.enforceSeek();<a
name="line.370"></a>
+<span class="sourceLineNo">371</span> } catch (IOException ioe) {<a
name="line.371"></a>
+<span class="sourceLineNo">372</span> // Add the item to delayed
close set in case it is leak from close<a name="line.372"></a>
+<span class="sourceLineNo">373</span>
this.scannersForDelayedClose.add(kvScanner);<a name="line.373"></a>
+<span class="sourceLineNo">374</span> throw ioe;<a
name="line.374"></a>
+<span class="sourceLineNo">375</span> }<a name="line.375"></a>
+<span class="sourceLineNo">376</span> Cell curKV = kvScanner.peek();<a
name="line.376"></a>
+<span class="sourceLineNo">377</span> if (curKV != null) {<a
name="line.377"></a>
+<span class="sourceLineNo">378</span> KeyValueScanner
nextEarliestScanner = heap.peek();<a name="line.378"></a>
+<span class="sourceLineNo">379</span> if (nextEarliestScanner ==
null) {<a name="line.379"></a>
+<span class="sourceLineNo">380</span> // The heap is empty. Return
the only possible scanner.<a name="line.380"></a>
+<span class="sourceLineNo">381</span> return kvScanner;<a
name="line.381"></a>
+<span class="sourceLineNo">382</span> }<a name="line.382"></a>
+<span class="sourceLineNo">383</span><a name="line.383"></a>
+<span class="sourceLineNo">384</span> // Compare the current scanner
to the next scanner. We try to avoid<a name="line.384"></a>
+<span class="sourceLineNo">385</span> // putting the current one back
into the heap if possible.<a name="line.385"></a>
+<span class="sourceLineNo">386</span> Cell nextKV =
nextEarliestScanner.peek();<a name="line.386"></a>
+<span class="sourceLineNo">387</span> if (nextKV == null ||
comparator.compare(curKV, nextKV) < 0) {<a name="line.387"></a>
+<span class="sourceLineNo">388</span> // We already have the
scanner with the earliest KV, so return it.<a name="line.388"></a>
+<span class="sourceLineNo">389</span> return kvScanner;<a
name="line.389"></a>
+<span class="sourceLineNo">390</span> }<a name="line.390"></a>
+<span class="sourceLineNo">391</span><a name="line.391"></a>
+<span class="sourceLineNo">392</span> // Otherwise, put the scanner
back into the heap and let it compete<a name="line.392"></a>
+<span class="sourceLineNo">393</span> // against all other scanners
(both those that have done a "real<a name="line.393"></a>
+<span class="sourceLineNo">394</span> // seek" and a "lazy seek").<a
name="line.394"></a>
+<span class="sourceLineNo">395</span> heap.add(kvScanner);<a
name="line.395"></a>
+<span class="sourceLineNo">396</span> } else {<a name="line.396"></a>
+<span class="sourceLineNo">397</span> // Close the scanner because we
did a real seek and found out there<a name="line.397"></a>
+<span class="sourceLineNo">398</span> // are no more KVs.<a
name="line.398"></a>
+<span class="sourceLineNo">399</span>
this.scannersForDelayedClose.add(kvScanner);<a name="line.399"></a>
+<span class="sourceLineNo">400</span> }<a name="line.400"></a>
+<span class="sourceLineNo">401</span> } else {<a name="line.401"></a>
+<span class="sourceLineNo">402</span> // Close the scanner because it
has already run out of KVs even before<a name="line.402"></a>
+<span class="sourceLineNo">403</span> // we had to do a real seek on
it.<a name="line.403"></a>
+<span class="sourceLineNo">404</span>
this.scannersForDelayedClose.add(kvScanner);<a name="line.404"></a>
+<span class="sourceLineNo">405</span> }<a name="line.405"></a>
+<span class="sourceLineNo">406</span> kvScanner = heap.poll();<a
name="line.406"></a>
+<span class="sourceLineNo">407</span> }<a name="line.407"></a>
+<span class="sourceLineNo">408</span><a name="line.408"></a>
+<span class="sourceLineNo">409</span> return kvScanner;<a
name="line.409"></a>
+<span class="sourceLineNo">410</span> }<a name="line.410"></a>
+<span class="sourceLineNo">411</span><a name="line.411"></a>
+<span class="sourceLineNo">412</span> /**<a name="line.412"></a>
+<span class="sourceLineNo">413</span> * @return the current Heap<a
name="line.413"></a>
+<span class="sourceLineNo">414</span> */<a name="line.414"></a>
+<span class="sourceLineNo">415</span> public
PriorityQueue<KeyValueScanner> getHeap() {<a name="line.415"></a>
+<span class="sourceLineNo">416</span> return this.heap;<a
name="line.416"></a>
+<span class="sourceLineNo">417</span> }<a name="line.417"></a>
+<span class="sourceLineNo">418</span><a name="line.418"></a>
+<span class="sourceLineNo">419</span> /**<a name="line.419"></a>
+<span class="sourceLineNo">420</span> * @see
KeyValueScanner#getScannerOrder()<a name="line.420"></a>
+<span class="sourceLineNo">421</span> */<a name="line.421"></a>
+<span class="sourceLineNo">422</span> @Override<a name="line.422"></a>
+<span class="sourceLineNo">423</span> public long getScannerOrder() {<a
name="line.423"></a>
+<span class="sourceLineNo">424</span> return 0;<a name="line.424"></a>
+<span class="sourceLineNo">425</span> }<a name="line.425"></a>
+<span class="sourceLineNo">426</span><a name="line.426"></a>
+<span class="sourceLineNo">427</span> @VisibleForTesting<a
name="line.427"></a>
+<span class="sourceLineNo">428</span> KeyValueScanner getCurrentForTesting()
{<a name="line.428"></a>
+<span class="sourceLineNo">429</span> return current;<a name="line.429"></a>
+<span class="sourceLineNo">430</span> }<a name="line.430"></a>
+<span class="sourceLineNo">431</span><a name="line.431"></a>
+<span class="sourceLineNo">432</span> @Override<a name="line.432"></a>
+<span class="sourceLineNo">433</span> public Cell getNextIndexedKey() {<a
name="line.433"></a>
+<span class="sourceLineNo">434</span> // here we return the next index key
from the top scanner<a name="line.434"></a>
+<span class="sourceLineNo">435</span> return current == null ? null :
current.getNextIndexedKey();<a name="line.435"></a>
+<span class="sourceLineNo">436</span> }<a name="line.436"></a>
+<span class="sourceLineNo">437</span><a name="line.437"></a>
+<span class="sourceLineNo">438</span> @Override<a name="line.438"></a>
+<span class="sourceLineNo">439</span> public void shipped() throws
IOException {<a name="line.439"></a>
+<span class="sourceLineNo">440</span> for (KeyValueScanner scanner :
this.scannersForDelayedClose) {<a name="line.440"></a>
+<span class="sourceLineNo">441</span> scanner.close(); // There wont be
further fetch of Cells from these scanners. Just close.<a name="line.441"></a>
+<span class="sourceLineNo">442</span> }<a name="line.442"></a>
+<span class="sourceLineNo">443</span>
this.scannersForDelayedClose.clear();<a name="line.443"></a>
+<span class="sourceLineNo">444</span> if (this.current != null) {<a
name="line.444"></a>
+<span class="sourceLineNo">445</span> this.current.shipped();<a
name="line.445"></a>
+<span class="sourceLineNo">446</span> }<a name="line.446"></a>
+<span class="sourceLineNo">447</span> if (this.heap != null) {<a
name="line.447"></a>
+<span class="sourceLineNo">448</span> for (KeyValueScanner scanner :
this.heap) {<a name="line.448"></a>
+<span class="sourceLineNo">449</span> scanner.shipped();<a
name="line.449"></a>
+<span class="sourceLineNo">450</span> }<a name="line.450"></a>
+<span class="sourceLineNo">451</span> }<a name="line.451"></a>
+<span class="sourceLineNo">452</span> }<a name="line.452"></a>
+<span class="sourceLineNo">453</span>}<a name="line.453"></a>
