WALPrettyPrinter (Apache HBase - Server 3.0.0-alpha-3 API)

java.lang.Object
- org.apache.hadoop.hbase.wal.WALPrettyPrinter

```
@InterfaceAudience.LimitedPrivate(value="Tools")
 @InterfaceStability.Evolving
public class WALPrettyPrinter
extends Object
```
WALPrettyPrinter prints the contents of a given WAL with a variety of options affecting formatting and extent of content. It targets two usage cases: pretty printing for ease of debugging directly by humans, and JSON output for consumption by monitoring and/or maintenance scripts. It can filter by row, region, or sequence id. It can also toggle output of values.

Constructor Summary

Constructors
Constructor and Description

WALPrettyPrinter()
Basic constructor that simply initializes values to reasonable defaults.

Constructors
Constructor and Description
`WALPrettyPrinter()` Basic constructor that simply initializes values to reasonable defaults.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`beginPersistentOutput()` enables output as a single, persistent list.
`void`	`disableJSON()` turns JSON output off, and turns on "pretty strings" for human consumption
`void`	`disableValues()` turns value output off
`void`	`enableJSON()` turns JSON output on
`void`	`enableValues()` turns value output on
`void`	`endPersistentOutput()` ends output of a single, persistent list.
`static void`	`main(String[] args)`
`static void`	`printCell(PrintStream out, Map<String,Object> op, boolean outputValues, boolean outputOnlyRowKey)`
`void`	`processFile(org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.fs.Path p)` reads a log file and outputs its contents, one transaction at a time, as specified by the currently configured options n * the HBase configuration relevant to this log file n * the path of the log file to be read n * may be unable to access the configured filesystem or requested file.
`static void`	`run(String[] args)` Pass one or more log file names and formatting options and it will dump out a text version of the contents on `stdout`.
`void`	`setOutputOnlyRowKey()` Option to print the row key only in case you just need the row keys from the WAL
`void`	`setPosition(long position)` sets the position to start seeking the WAL file n * initial position to start seeking the given WAL file
`void`	`setRegionFilter(String region)` sets the region by which output will be filtered n * when not null, serves as a filter; only log entries from this region will be printed
`void`	`setRowFilter(String row)` sets the row key by which output will be filtered n * when not null, serves as a filter; only log entries from this row will be printed
`void`	`setRowPrefixFilter(String rowPrefix)` sets the rowPrefix key prefix by which output will be filtered n * when not null, serves as a filter; only log entries with rows having this prefix will be printed
`void`	`setSequenceFilter(long sequence)` sets the region by which output will be filtered n * when nonnegative, serves as a filter; only log entries with this sequence id will be printed
`void`	`setTableFilter(String tablesWithDelimiter)` Sets the tables filter.
`static Map<String,Object>`	`toStringMap(Cell cell)`
`static Map<String,Object>`	`toStringMap(Cell cell, boolean printRowKeyOnly, String rowPrefix, String row, boolean outputValues)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - WALPrettyPrinter
```
public WALPrettyPrinter()
```
    Basic constructor that simply initializes values to reasonable defaults.
- Method Detail
  - enableValues
```
public void enableValues()
```
    turns value output on
  - disableValues
```
public void disableValues()
```
    turns value output off
  - enableJSON
```
public void enableJSON()
```
    turns JSON output on
  - disableJSON
```
public void disableJSON()
```
    turns JSON output off, and turns on "pretty strings" for human consumption
  - setSequenceFilter
```
public void setSequenceFilter(long sequence)
```
    sets the region by which output will be filtered n * when nonnegative, serves as a filter; only log entries with this sequence id will be printed
  - setTableFilter
```
public void setTableFilter(String tablesWithDelimiter)
```
    Sets the tables filter. Only log entries for these tables are printed.
    
    Parameters:
    
    tablesWithDelimiter - table names separated with comma.
  - setRegionFilter
```
public void setRegionFilter(String region)
```
    sets the region by which output will be filtered n * when not null, serves as a filter; only log entries from this region will be printed
  - setRowFilter
```
public void setRowFilter(String row)
```
    sets the row key by which output will be filtered n * when not null, serves as a filter; only log entries from this row will be printed
  - setRowPrefixFilter
```
public void setRowPrefixFilter(String rowPrefix)
```
    sets the rowPrefix key prefix by which output will be filtered n * when not null, serves as a filter; only log entries with rows having this prefix will be printed
  - setOutputOnlyRowKey
```
public void setOutputOnlyRowKey()
```
    Option to print the row key only in case you just need the row keys from the WAL
  - setPosition
```
public void setPosition(long position)
```
    sets the position to start seeking the WAL file n * initial position to start seeking the given WAL file
  - beginPersistentOutput
```
public void beginPersistentOutput()
```
    enables output as a single, persistent list. at present, only relevant in the case of JSON output.
  - endPersistentOutput
```
public void endPersistentOutput()
```
    ends output of a single, persistent list. at present, only relevant in the case of JSON output.
  - processFile
```
public void processFile(org.apache.hadoop.conf.Configuration conf,
                        org.apache.hadoop.fs.Path p)
                 throws IOException
```
    reads a log file and outputs its contents, one transaction at a time, as specified by the currently configured options n * the HBase configuration relevant to this log file n * the path of the log file to be read n * may be unable to access the configured filesystem or requested file.
    
    Throws:
    
    IOException
  - printCell
```
public static void printCell(PrintStream out,
                             Map<String,Object> op,
                             boolean outputValues,
                             boolean outputOnlyRowKey)
```
  - toStringMap
```
public static Map<String,Object> toStringMap(Cell cell,
                                             boolean printRowKeyOnly,
                                             String rowPrefix,
                                             String row,
                                             boolean outputValues)
```
  - toStringMap
```
public static Map<String,Object> toStringMap(Cell cell)
```
  - main
```
public static void main(String[] args)
                 throws IOException
```
    Throws:
    
    IOException
  - run
```
public static void run(String[] args)
                throws IOException
```
    Pass one or more log file names and formatting options and it will dump out a text version of the contents on stdout. n * Command line arguments n * Thrown upon file system errors etc.
    
    Throws:
    
    IOException

Class WALPrettyPrinter

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

WALPrettyPrinter

Method Detail

enableValues

disableValues

enableJSON

disableJSON

setSequenceFilter

setTableFilter

setRegionFilter

setRowFilter

setRowPrefixFilter

setOutputOnlyRowKey

setPosition

beginPersistentOutput

endPersistentOutput

processFile

printCell

toStringMap

toStringMap

main

run