CompoundConfiguration (Apache HBase 1.2.12 API)

java.lang.Object
- org.apache.hadoop.conf.Configuration
- - org.apache.hadoop.hbase.CompoundConfiguration

All Implemented Interfaces:

Iterable<Map.Entry<String,String>>, org.apache.hadoop.io.Writable
```
@InterfaceAudience.Private
public class CompoundConfiguration
extends org.apache.hadoop.conf.Configuration
```
Do a shallow merge of multiple KV configuration pools. This is a very useful utility class to easily add per-object configurations in addition to wider scope settings. This is different from Configuration.addResource() functionality, which performs a deep merge and mutates the common data structure.
The iterator on CompoundConfiguration is unmodifiable. Obtaining iterator is an expensive operation.
For clarity: the shallow merge allows the user to mutate either of the configuration objects and have changes reflected everywhere. In contrast to a deep merge, that requires you to explicitly know all applicable copies to propagate changes. WARNING: The values set in the CompoundConfiguration are do not handle Property variable substitution. However, if they are set in the underlying configuration substitutions are done.

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`private static interface`	`CompoundConfiguration.ImmutableConfigMap`
`(package private) static class`	`CompoundConfiguration.ImmutableConfWrapper`

Nested classes/interfaces inherited from class org.apache.hadoop.conf.Configuration
org.apache.hadoop.conf.Configuration.DeprecationDelta, org.apache.hadoop.conf.Configuration.IntegerRanges

Field Summary

Fields
Modifier and Type Field and Description

protected List<CompoundConfiguration.ImmutableConfigMap> configs

private org.apache.hadoop.conf.Configuration mutableConf

Fields
Modifier and Type	Field and Description
`protected List<CompoundConfiguration.ImmutableConfigMap>`	`configs`
`private org.apache.hadoop.conf.Configuration`	`mutableConf`

Constructor Summary

Constructors
Constructor and Description

CompoundConfiguration()
Default Constructor.

Constructors
Constructor and Description
`CompoundConfiguration()` Default Constructor.

Method Summary

Methods
Modifier and Type	Method and Description
`CompoundConfiguration`	`add(org.apache.hadoop.conf.Configuration conf)` Add Hadoop Configuration object to config list.
`CompoundConfiguration`	`addStringMap(Map<String,String> map)` Add String map to config list.
`CompoundConfiguration`	`addWritableMap(Map<ImmutableBytesWritable,ImmutableBytesWritable> map)` Add ImmutableBytesWritable map to config list.
`void`	`clear()` These methods are unsupported, and no code using CompoundConfiguration depend upon them.
`(package private) void`	`freezeMutableConf()` If set has been called, it will create a mutableConf.
`String`	`get(String key)`
`String`	`get(String name, String defaultValue)` Get the value of the `name`.
`Class<?>`	`getClassByName(String name)`
`String`	`getRaw(String key)`
`Iterator<Map.Entry<String,String>>`	`iterator()`
`void`	`set(String name, String value)`
`int`	`size()`
`String`	`toString()`
`void`	`write(DataOutput out)`
`void`	`writeXml(OutputStream out)`

Methods inherited from class org.apache.hadoop.conf.Configuration
addDefaultResource, addDeprecation, addDeprecation, addDeprecation, addDeprecation, addDeprecations, addResource, addResource, addResource, addResource, addResource, addResource, dumpConfiguration, dumpDeprecatedKeys, getBoolean, getClass, getClass, getClassByNameOrNull, getClasses, getClassLoader, getConfResourceAsInputStream, getConfResourceAsReader, getDouble, getEnum, getFile, getFinalParameters, getFloat, getInstances, getInt, getInts, getLocalPath, getLong, getLongBytes, getPattern, getPropertySources, getProps, getRange, getResource, getSocketAddr, getStringCollection, getStrings, getStrings, getTimeDuration, getTrimmed, getTrimmed, getTrimmedStringCollection, getTrimmedStrings, getTrimmedStrings, getValByRegex, hasWarnedDeprecation, isDeprecated, main, readFields, reloadConfiguration, set, setBoolean, setBooleanIfUnset, setClass, setClassLoader, setDouble, setEnum, setFloat, setIfUnset, setInt, setLong, setPattern, setQuietMode, setSocketAddr, setStrings, setTimeDuration, unset, updateConnectAddr, writeXml

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

- Field Detail
  - mutableConf
```
private org.apache.hadoop.conf.Configuration mutableConf
```
  - configs
```
protected List<CompoundConfiguration.ImmutableConfigMap> configs
```
- Constructor Detail
  - CompoundConfiguration
```
public CompoundConfiguration()
```
    Default Constructor. Initializes empty configuration
- Method Detail
  - freezeMutableConf
```
void freezeMutableConf()
```
    If set has been called, it will create a mutableConf. This converts the mutableConf to an immutable one and resets it to allow a new mutable conf. This is used when a new map or conf is added to the compound configuration to preserve proper override semantics.
  - add
```
public CompoundConfiguration add(org.apache.hadoop.conf.Configuration conf)
```
    Add Hadoop Configuration object to config list. The added configuration overrides the previous ones if there are name collisions.
    
    Parameters:
    conf - configuration object
    
    Returns:
    this, for builder pattern
  - addWritableMap
```
public CompoundConfiguration addWritableMap(Map<ImmutableBytesWritable,ImmutableBytesWritable> map)
```
    Add ImmutableBytesWritable map to config list. This map is generally created by HTableDescriptor or HColumnDescriptor, but can be abstractly used. The added configuration overrides the previous ones if there are name collisions.
    
    Parameters:
    map - ImmutableBytesWritable map
    
    Returns:
    this, for builder pattern
  - addStringMap
```
public CompoundConfiguration addStringMap(Map<String,String> map)
```
    Add String map to config list. This map is generally created by HTableDescriptor or HColumnDescriptor, but can be abstractly used. The added configuration overrides the previous ones if there are name collisions.
    
    Returns:
    this, for builder pattern
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class org.apache.hadoop.conf.Configuration
  - get
```
public String get(String key)
```
    Overrides:
    
    get in class org.apache.hadoop.conf.Configuration
  - getRaw
```
public String getRaw(String key)
```
    Overrides:
    
    getRaw in class org.apache.hadoop.conf.Configuration
  - getClassByName
```
public Class<?> getClassByName(String name)
                        throws ClassNotFoundException
```
    Overrides:
    
    getClassByName in class org.apache.hadoop.conf.Configuration
    
    Throws:
    
    ClassNotFoundException
  - size
```
public int size()
```
    Overrides:
    
    size in class org.apache.hadoop.conf.Configuration
  - get
```
public String get(String name,
         String defaultValue)
```
    Get the value of the name. If the key is deprecated, it returns the value of the first key which replaces the deprecated key and is not null. If no such property exists, then defaultValue is returned. The CompooundConfiguration does not do property substitution. To do so we need Configuration.getProps to be protected or package visible. Though in hadoop2 it is protected, in hadoop1 the method is private and not accessible. All of the get* methods call this overridden get method.
    
    Overrides:
    
    get in class org.apache.hadoop.conf.Configuration
    
    Parameters:
    name - property name.
    defaultValue - default value.
    
    Returns:
    property value, or defaultValue if the property doesn't exist.
  - iterator
```
public Iterator<Map.Entry<String,String>> iterator()
```
    Specified by:
    
    iterator in interface Iterable<Map.Entry<String,String>>
    
    Overrides:
    
    iterator in class org.apache.hadoop.conf.Configuration
  - set
```
public void set(String name,
       String value)
```
    Overrides:
    
    set in class org.apache.hadoop.conf.Configuration
  - clear
```
public void clear()
```
    These methods are unsupported, and no code using CompoundConfiguration depend upon them. Quickly abort upon any attempts to use them.
    
    Overrides:
    
    clear in class org.apache.hadoop.conf.Configuration
  - write
```
public void write(DataOutput out)
           throws IOException
```
    Specified by:
    
    write in interface org.apache.hadoop.io.Writable
    
    Overrides:
    
    write in class org.apache.hadoop.conf.Configuration
    
    Throws:
    
    IOException
  - writeXml
```
public void writeXml(OutputStream out)
              throws IOException
```
    Overrides:
    
    writeXml in class org.apache.hadoop.conf.Configuration
    
    Throws:
    
    IOException

Class CompoundConfiguration

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.conf.Configuration

Field Summary

Constructor Summary

Method Summary

Methods inherited from class org.apache.hadoop.conf.Configuration

Methods inherited from class java.lang.Object

Field Detail

mutableConf

configs

Constructor Detail

CompoundConfiguration

Method Detail

freezeMutableConf

add

addWritableMap

addStringMap

toString

get

getRaw

getClassByName

size

get

iterator

set

clear

write

writeXml