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| 91 | org.apache.hadoop.mapreduce.lib.partition</FONT> |
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| 93 | Class HashPartitioner<K,V></H2> |
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| 94 | <PRE> |
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| 95 | <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">java.lang.Object</A> |
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| 96 | <IMG SRC="../../../../../../resources/inherit.gif" ALT="extended by "><A HREF="../../../../../../org/apache/hadoop/mapreduce/Partitioner.html" title="class in org.apache.hadoop.mapreduce">org.apache.hadoop.mapreduce.Partitioner</A><K,V> |
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| 100 | <DL> |
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| 101 | <DT><PRE>public class <B>HashPartitioner<K,V></B><DT>extends <A HREF="../../../../../../org/apache/hadoop/mapreduce/Partitioner.html" title="class in org.apache.hadoop.mapreduce">Partitioner</A><K,V></DL> |
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| 102 | </PRE> |
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| 103 | |
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| 104 | <P> |
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| 105 | Partition keys by their <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#hashCode()" title="class or interface in java.lang"><CODE>Object.hashCode()</CODE></A>. |
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| 122 | <TD><CODE><B><A HREF="../../../../../../org/apache/hadoop/mapreduce/lib/partition/HashPartitioner.html#HashPartitioner()">HashPartitioner</A></B>()</CODE> |
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| 139 | <CODE> int</CODE></FONT></TD> |
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| 140 | <TD><CODE><B><A HREF="../../../../../../org/apache/hadoop/mapreduce/lib/partition/HashPartitioner.html#getPartition(K, V, int)">getPartition</A></B>(<A HREF="../../../../../../org/apache/hadoop/mapreduce/lib/partition/HashPartitioner.html" title="type parameter in HashPartitioner">K</A> key, |
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| 141 | <A HREF="../../../../../../org/apache/hadoop/mapreduce/lib/partition/HashPartitioner.html" title="type parameter in HashPartitioner">V</A> value, |
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| 142 | int numReduceTasks)</CODE> |
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| 143 | |
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| 144 | <BR> |
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| 145 | Use <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#hashCode()" title="class or interface in java.lang"><CODE>Object.hashCode()</CODE></A> to partition.</TD> |
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| 169 | |
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| 170 | <A NAME="HashPartitioner()"><!-- --></A><H3> |
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| 171 | HashPartitioner</H3> |
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| 172 | <PRE> |
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| 173 | public <B>HashPartitioner</B>()</PRE> |
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| 174 | <DL> |
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| 186 | |
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| 187 | <A NAME="getPartition(java.lang.Object,java.lang.Object,int)"><!-- --></A><A NAME="getPartition(K, V, int)"><!-- --></A><H3> |
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| 188 | getPartition</H3> |
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| 189 | <PRE> |
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| 190 | public int <B>getPartition</B>(<A HREF="../../../../../../org/apache/hadoop/mapreduce/lib/partition/HashPartitioner.html" title="type parameter in HashPartitioner">K</A> key, |
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| 191 | <A HREF="../../../../../../org/apache/hadoop/mapreduce/lib/partition/HashPartitioner.html" title="type parameter in HashPartitioner">V</A> value, |
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| 192 | int numReduceTasks)</PRE> |
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| 193 | <DL> |
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| 194 | <DD>Use <A HREF="http://java.sun.com/javase/6/docs/api/java/lang/Object.html?is-external=true#hashCode()" title="class or interface in java.lang"><CODE>Object.hashCode()</CODE></A> to partition. |
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| 195 | <P> |
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| 196 | <DD><DL> |
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| 197 | <DT><B>Specified by:</B><DD><CODE><A HREF="../../../../../../org/apache/hadoop/mapreduce/Partitioner.html#getPartition(KEY, VALUE, int)">getPartition</A></CODE> in class <CODE><A HREF="../../../../../../org/apache/hadoop/mapreduce/Partitioner.html" title="class in org.apache.hadoop.mapreduce">Partitioner</A><<A HREF="../../../../../../org/apache/hadoop/mapreduce/lib/partition/HashPartitioner.html" title="type parameter in HashPartitioner">K</A>,<A HREF="../../../../../../org/apache/hadoop/mapreduce/lib/partition/HashPartitioner.html" title="type parameter in HashPartitioner">V</A>></CODE></DL> |
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| 198 | </DD> |
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| 199 | <DD><DL> |
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| 200 | <DT><B>Parameters:</B><DD><CODE>key</CODE> - the key to be partioned.<DD><CODE>value</CODE> - the entry value.<DD><CODE>numReduceTasks</CODE> - the total number of partitions. |
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| 201 | <DT><B>Returns:</B><DD>the partition number for the <code>key</code>.</DL> |
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| 202 | </DD> |
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