org.apache.hadoop.mapred.lib

クラス KeyFieldBasedComparator<K,V>

java.lang.Object

org.apache.hadoop.io.WritableComparator

org.apache.hadoop.mapreduce.lib.partition.KeyFieldBasedComparator<K,V>

org.apache.hadoop.mapred.lib.KeyFieldBasedComparator<K,V>

すべての実装されたインタフェース:

Comparator, Configurable, RawComparator, JobConfigurable

@InterfaceAudience.Public
 @InterfaceStability.Stable
public class KeyFieldBasedComparator<K,V>
extends KeyFieldBasedComparator<K,V>
implements JobConfigurable

This comparator implementation provides a subset of the features provided by the Unix/GNU Sort. In particular, the supported features are: -n, (Sort numerically) -r, (Reverse the result of comparison) -k pos1[,pos2], where pos is of the form f[.c][opts], where f is the number of the field to use, and c is the number of the first character from the beginning of the field. Fields and character posns are numbered starting with 1; a character position of zero in pos2 indicates the field's last character. If '.c' is omitted from pos1, it defaults to 1 (the beginning of the field); if omitted from pos2, it defaults to 0 (the end of the field). opts are ordering options (any of 'nr' as described above). We assume that the fields in the key are separated by MRJobConfig.MAP_OUTPUT_KEY_FIELD_SEPERATOR

フィールドのサマリー

クラスから継承されたフィールド org.apache.hadoop.mapreduce.lib.partition.KeyFieldBasedComparator

COMPARATOR_OPTIONS

コンストラクタのサマリー

コンストラクタ

コンストラクタと説明
KeyFieldBasedComparator()

メソッドのサマリー

修飾子とタイプ	メソッドと説明
void	configure(JobConf job) Initializes a new instance from a JobConf.

クラスから継承されたメソッド org.apache.hadoop.mapreduce.lib.partition.KeyFieldBasedComparator

compare, getConf, getKeyFieldComparatorOption, setConf, setKeyFieldComparatorOptions

クラスから継承されたメソッド org.apache.hadoop.io.WritableComparator

compare, compare, compareBytes, define, get, get, getKeyClass, hashBytes, hashBytes, newKey, readDouble, readFloat, readInt, readLong, readUnsignedShort, readVInt, readVLong

クラスから継承されたメソッド java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

インタフェースから継承されたメソッド java.util.Comparator

comparing, comparing, comparingDouble, comparingInt, comparingLong, equals, naturalOrder, nullsFirst, nullsLast, reversed, reverseOrder, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

コンストラクタの詳細

KeyFieldBasedComparator

public KeyFieldBasedComparator()

メソッドの詳細

configure

public void configure(JobConf job)

インタフェースからコピーされた説明: JobConfigurable

Initializes a new instance from a JobConf.

定義:

configure インタフェース内 JobConfigurable

パラメータ:

job - the configuration