Package org.apache.hadoop.hbase.mapred
Class TableMapReduceUtil
java.lang.Object
org.apache.hadoop.hbase.mapred.TableMapReduceUtil
Utility for
TableMap
and TableReduce
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Field Summary
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Constructor Summary
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Method Summary
Modifier and TypeMethodDescriptionstatic void
addDependencyJars
(org.apache.hadoop.mapred.JobConf job) private static int
getRegionCount
(org.apache.hadoop.conf.Configuration conf, TableName tableName) static void
initCredentials
(org.apache.hadoop.mapred.JobConf job) static void
initMultiTableSnapshotMapperJob
(Map<String, Collection<Scan>> snapshotScans, Class<? extends TableMap> mapper, Class<?> outputKeyClass, Class<?> outputValueClass, org.apache.hadoop.mapred.JobConf job, boolean addDependencyJars, org.apache.hadoop.fs.Path tmpRestoreDir) Sets up the job for reading from one or more multiple table snapshots, with one or more scans per snapshot.static void
initTableMapJob
(String table, String columns, Class<? extends TableMap> mapper, Class<?> outputKeyClass, Class<?> outputValueClass, org.apache.hadoop.mapred.JobConf job) Use this before submitting a TableMap job.static void
initTableMapJob
(String table, String columns, Class<? extends TableMap> mapper, Class<?> outputKeyClass, Class<?> outputValueClass, org.apache.hadoop.mapred.JobConf job, boolean addDependencyJars) static void
initTableMapJob
(String table, String columns, Class<? extends TableMap> mapper, Class<?> outputKeyClass, Class<?> outputValueClass, org.apache.hadoop.mapred.JobConf job, boolean addDependencyJars, Class<? extends org.apache.hadoop.mapred.InputFormat> inputFormat) Use this before submitting a TableMap job.static void
initTableReduceJob
(String table, Class<? extends TableReduce> reducer, org.apache.hadoop.mapred.JobConf job) Use this before submitting a TableReduce job.static void
initTableReduceJob
(String table, Class<? extends TableReduce> reducer, org.apache.hadoop.mapred.JobConf job, Class partitioner) Use this before submitting a TableReduce job.static void
initTableReduceJob
(String table, Class<? extends TableReduce> reducer, org.apache.hadoop.mapred.JobConf job, Class partitioner, boolean addDependencyJars) Use this before submitting a TableReduce job.static void
initTableSnapshotMapJob
(String snapshotName, String columns, Class<? extends TableMap> mapper, Class<?> outputKeyClass, Class<?> outputValueClass, org.apache.hadoop.mapred.JobConf job, boolean addDependencyJars, org.apache.hadoop.fs.Path tmpRestoreDir) Sets up the job for reading from a table snapshot.static void
initTableSnapshotMapJob
(String snapshotName, String columns, Class<? extends TableMap> mapper, Class<?> outputKeyClass, Class<?> outputValueClass, org.apache.hadoop.mapred.JobConf jobConf, boolean addDependencyJars, org.apache.hadoop.fs.Path tmpRestoreDir, RegionSplitter.SplitAlgorithm splitAlgo, int numSplitsPerRegion) Sets up the job for reading from a table snapshot.static void
limitNumMapTasks
(String table, org.apache.hadoop.mapred.JobConf job) Ensures that the given number of map tasks for the given job configuration does not exceed the number of regions for the given table.static void
limitNumReduceTasks
(String table, org.apache.hadoop.mapred.JobConf job) Ensures that the given number of reduce tasks for the given job configuration does not exceed the number of regions for the given table.static void
setNumMapTasks
(String table, org.apache.hadoop.mapred.JobConf job) Sets the number of map tasks for the given job configuration to the number of regions the given table has.static void
setNumReduceTasks
(String table, org.apache.hadoop.mapred.JobConf job) Sets the number of reduce tasks for the given job configuration to the number of regions the given table has.static void
setScannerCaching
(org.apache.hadoop.mapred.JobConf job, int batchSize) Sets the number of rows to return and cache with each scanner iteration.
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Field Details
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LOG
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Constructor Details
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TableMapReduceUtil
public TableMapReduceUtil()
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Method Details
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initTableMapJob
public static void initTableMapJob(String table, String columns, Class<? extends TableMap> mapper, Class<?> outputKeyClass, Class<?> outputValueClass, org.apache.hadoop.mapred.JobConf job) Use this before submitting a TableMap job. It will appropriately set up the JobConf.- Parameters:
table
- The table name to read from.columns
- The columns to scan.mapper
- The mapper class to use.outputKeyClass
- The class of the output key.outputValueClass
- The class of the output value.job
- The current job configuration to adjust.
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initTableMapJob
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initTableMapJob
public static void initTableMapJob(String table, String columns, Class<? extends TableMap> mapper, Class<?> outputKeyClass, Class<?> outputValueClass, org.apache.hadoop.mapred.JobConf job, boolean addDependencyJars, Class<? extends org.apache.hadoop.mapred.InputFormat> inputFormat) Use this before submitting a TableMap job. It will appropriately set up the JobConf.- Parameters:
table
- The table name to read from.columns
- The columns to scan.mapper
- The mapper class to use.outputKeyClass
- The class of the output key.outputValueClass
- The class of the output value.job
- The current job configuration to adjust.addDependencyJars
- upload HBase jars and jars for any of the configured job classes via the distributed cache (tmpjars).
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initMultiTableSnapshotMapperJob
public static void initMultiTableSnapshotMapperJob(Map<String, Collection<Scan>> snapshotScans, Class<? extends TableMap> mapper, Class<?> outputKeyClass, Class<?> outputValueClass, org.apache.hadoop.mapred.JobConf job, boolean addDependencyJars, org.apache.hadoop.fs.Path tmpRestoreDir) throws IOExceptionSets up the job for reading from one or more multiple table snapshots, with one or more scans per snapshot. It bypasses hbase servers and read directly from snapshot files.- Parameters:
snapshotScans
- map of snapshot name to scans on that snapshot.mapper
- The mapper class to use.outputKeyClass
- The class of the output key.outputValueClass
- The class of the output value.job
- The current job to adjust. Make sure the passed job is carrying all necessary HBase configuration.addDependencyJars
- upload HBase jars and jars for any of the configured job classes via the distributed cache (tmpjars).- Throws:
IOException
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initTableSnapshotMapJob
public static void initTableSnapshotMapJob(String snapshotName, String columns, Class<? extends TableMap> mapper, Class<?> outputKeyClass, Class<?> outputValueClass, org.apache.hadoop.mapred.JobConf job, boolean addDependencyJars, org.apache.hadoop.fs.Path tmpRestoreDir) throws IOException Sets up the job for reading from a table snapshot. It bypasses hbase servers and read directly from snapshot files.- Parameters:
snapshotName
- The name of the snapshot (of a table) to read from.columns
- The columns to scan.mapper
- The mapper class to use.outputKeyClass
- The class of the output key.outputValueClass
- The class of the output value.job
- The current job to adjust. Make sure the passed job is carrying all necessary HBase configuration.addDependencyJars
- upload HBase jars and jars for any of the configured job classes via the distributed cache (tmpjars).tmpRestoreDir
- a temporary directory to copy the snapshot files into. Current user should have write permissions to this directory, and this should not be a subdirectory of rootdir. After the job is finished, restore directory can be deleted.- Throws:
IOException
- When setting up the details fails.- See Also:
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initTableSnapshotMapJob
public static void initTableSnapshotMapJob(String snapshotName, String columns, Class<? extends TableMap> mapper, Class<?> outputKeyClass, Class<?> outputValueClass, org.apache.hadoop.mapred.JobConf jobConf, boolean addDependencyJars, org.apache.hadoop.fs.Path tmpRestoreDir, RegionSplitter.SplitAlgorithm splitAlgo, int numSplitsPerRegion) throws IOException Sets up the job for reading from a table snapshot. It bypasses hbase servers and read directly from snapshot files.- Parameters:
snapshotName
- The name of the snapshot (of a table) to read from.columns
- The columns to scan.mapper
- The mapper class to use.outputKeyClass
- The class of the output key.outputValueClass
- The class of the output value.jobConf
- The current job to adjust. Make sure the passed job is carrying all necessary HBase configuration.addDependencyJars
- upload HBase jars and jars for any of the configured job classes via the distributed cache (tmpjars).tmpRestoreDir
- a temporary directory to copy the snapshot files into. Current user should have write permissions to this directory, and this should not be a subdirectory of rootdir. After the job is finished, restore directory can be deleted.splitAlgo
- algorithm to splitnumSplitsPerRegion
- how many input splits to generate per one region- Throws:
IOException
- When setting up the details fails.- See Also:
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initTableReduceJob
public static void initTableReduceJob(String table, Class<? extends TableReduce> reducer, org.apache.hadoop.mapred.JobConf job) throws IOException Use this before submitting a TableReduce job. It will appropriately set up the JobConf.- Parameters:
table
- The output table.reducer
- The reducer class to use.job
- The current job configuration to adjust.- Throws:
IOException
- When determining the region count fails.
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initTableReduceJob
public static void initTableReduceJob(String table, Class<? extends TableReduce> reducer, org.apache.hadoop.mapred.JobConf job, Class partitioner) throws IOException Use this before submitting a TableReduce job. It will appropriately set up the JobConf.- Parameters:
table
- The output table.reducer
- The reducer class to use.job
- The current job configuration to adjust.partitioner
- Partitioner to use. Passnull
to use default partitioner.- Throws:
IOException
- When determining the region count fails.
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initTableReduceJob
public static void initTableReduceJob(String table, Class<? extends TableReduce> reducer, org.apache.hadoop.mapred.JobConf job, Class partitioner, boolean addDependencyJars) throws IOException Use this before submitting a TableReduce job. It will appropriately set up the JobConf.- Parameters:
table
- The output table.reducer
- The reducer class to use.job
- The current job configuration to adjust.partitioner
- Partitioner to use. Passnull
to use default partitioner.addDependencyJars
- upload HBase jars and jars for any of the configured job classes via the distributed cache (tmpjars).- Throws:
IOException
- When determining the region count fails.
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initCredentials
- Throws:
IOException
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limitNumReduceTasks
public static void limitNumReduceTasks(String table, org.apache.hadoop.mapred.JobConf job) throws IOException Ensures that the given number of reduce tasks for the given job configuration does not exceed the number of regions for the given table.- Parameters:
table
- The table to get the region count for.job
- The current job configuration to adjust.- Throws:
IOException
- When retrieving the table details fails.
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limitNumMapTasks
public static void limitNumMapTasks(String table, org.apache.hadoop.mapred.JobConf job) throws IOException Ensures that the given number of map tasks for the given job configuration does not exceed the number of regions for the given table.- Parameters:
table
- The table to get the region count for.job
- The current job configuration to adjust.- Throws:
IOException
- When retrieving the table details fails.
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setNumReduceTasks
public static void setNumReduceTasks(String table, org.apache.hadoop.mapred.JobConf job) throws IOException Sets the number of reduce tasks for the given job configuration to the number of regions the given table has.- Parameters:
table
- The table to get the region count for.job
- The current job configuration to adjust.- Throws:
IOException
- When retrieving the table details fails.
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setNumMapTasks
public static void setNumMapTasks(String table, org.apache.hadoop.mapred.JobConf job) throws IOException Sets the number of map tasks for the given job configuration to the number of regions the given table has.- Parameters:
table
- The table to get the region count for.job
- The current job configuration to adjust.- Throws:
IOException
- When retrieving the table details fails.
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setScannerCaching
Sets the number of rows to return and cache with each scanner iteration. Higher caching values will enable faster mapreduce jobs at the expense of requiring more heap to contain the cached rows.- Parameters:
job
- The current job configuration to adjust.batchSize
- The number of rows to return in batch with each scanner iteration.
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addDependencyJars
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getRegionCount
private static int getRegionCount(org.apache.hadoop.conf.Configuration conf, TableName tableName) throws IOException - Throws:
IOException
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