ZKConfig (Apache HBase 1.4.11 API)

java.lang.Object
- org.apache.hadoop.hbase.zookeeper.ZKConfig

```
@InterfaceAudience.Private
public final class ZKConfig
extends Object
```
Utility methods for reading, and building the ZooKeeper configuration. The order and priority for reading the config are as follows: (1). zoo.cfg if ""hbase.config.read.zookeeper.config" is true (2). Property with "hbase.zookeeper.property." prefix from HBase XML (3). other zookeeper related properties in HBASE XML

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static class ZKConfig.ZKClusterKey

Nested Classes
Modifier and Type	Class and Description
`static class`	`ZKConfig.ZKClusterKey`

Method Summary

Methods
Modifier and Type	Method and Description
`static String`	`buildZKQuorumServerString(String[] serverHosts, String clientPort)` Build the ZK quorum server string with "server:clientport" list, separated by ','
`static String`	`getZKQuorumServersString(org.apache.hadoop.conf.Configuration conf)` Return the ZK Quorum servers string given the specified configuration.
`static String`	`getZooKeeperClusterKey(org.apache.hadoop.conf.Configuration conf)` Get the key to the ZK ensemble for this configuration without adding a name at the end
`static String`	`getZooKeeperClusterKey(org.apache.hadoop.conf.Configuration conf, String name)` Get the key to the ZK ensemble for this configuration and append a name at the end
`static Properties`	`makeZKProps(org.apache.hadoop.conf.Configuration conf)` Make a Properties object holding ZooKeeper config.
`static Properties`	`parseZooCfg(org.apache.hadoop.conf.Configuration conf, InputStream inputStream)` Deprecated. in 0.96 onwards. HBase will no longer rely on zoo.cfg availability.
`static String`	`standardizeZKQuorumServerString(String quorumStringInput, String clientPort)` Standardize the ZK quorum string: make it a "server:clientport" list, separated by ','
`static ZKConfig.ZKClusterKey`	`transformClusterKey(String key)` Separate the given key into the three configurations it should contain: hbase.zookeeper.quorum, hbase.zookeeper.client.port and zookeeper.znode.parent
`static void`	`validateClusterKey(String key)` Verifies that the given key matches the expected format for a ZooKeeper cluster key.

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

- Method Detail
  - makeZKProps
```
public static Properties makeZKProps(org.apache.hadoop.conf.Configuration conf)
```
    Make a Properties object holding ZooKeeper config. Parses the corresponding config options from the HBase XML configs and generates the appropriate ZooKeeper properties.
    
    Parameters:
    conf - Configuration to read from.
    
    Returns:
    Properties holding mappings representing ZooKeeper config file.
  - parseZooCfg
```
@Deprecated
public static Properties parseZooCfg(org.apache.hadoop.conf.Configuration conf,
                                InputStream inputStream)
                              throws IOException
```
    Deprecated. in 0.96 onwards. HBase will no longer rely on zoo.cfg availability.
    
    Parse ZooKeeper's zoo.cfg, injecting HBase Configuration variables in. This method is used for testing so we can pass our own InputStream.
    
    Parameters:
    conf - HBaseConfiguration to use for injecting variables.
    inputStream - InputStream to read from.
    
    Returns:
    Properties parsed from config stream with variables substituted.
    
    Throws:
    
    IOException - if anything goes wrong parsing config
  - getZKQuorumServersString
```
public static String getZKQuorumServersString(org.apache.hadoop.conf.Configuration conf)
```
    Return the ZK Quorum servers string given the specified configuration.
    
    Parameters:
    conf -
    
    Returns:
    Quorum servers
  - buildZKQuorumServerString
```
public static String buildZKQuorumServerString(String[] serverHosts,
                               String clientPort)
```
    Build the ZK quorum server string with "server:clientport" list, separated by ','
    
    Parameters:
    serverHosts - a list of servers for ZK quorum
    clientPort - the default client port
    
    Returns:
    the string for a list of "server:port" separated by ","
  - validateClusterKey
```
public static void validateClusterKey(String key)
                               throws IOException
```
    Verifies that the given key matches the expected format for a ZooKeeper cluster key. The Quorum for the ZK cluster can have one the following formats (see examples below):
    1. s1,s2,s3 (no client port in the list, the client port could be obtained from clientPort)
    2. s1:p1,s2:p2,s3:p3 (with client port, which could be same or different for each server, in this case, the clientPort would be ignored)
    3. s1:p1,s2,s3:p3 (mix of (1) and (2) - if port is not specified in a server, it would use the clientPort; otherwise, it would use the specified port)
    Parameters:
    key - the cluster key to validate
    
    Throws:
    
    IOException - if the key could not be parsed
  - transformClusterKey
```
public static ZKConfig.ZKClusterKey transformClusterKey(String key)
                                                 throws IOException
```
    Separate the given key into the three configurations it should contain: hbase.zookeeper.quorum, hbase.zookeeper.client.port and zookeeper.znode.parent
    
    Parameters:
    key -
    
    Returns:
    the three configuration in the described order
    
    Throws:
    
    IOException
  - getZooKeeperClusterKey
```
public static String getZooKeeperClusterKey(org.apache.hadoop.conf.Configuration conf)
```
    Get the key to the ZK ensemble for this configuration without adding a name at the end
    
    Parameters:
    conf - Configuration to use to build the key
    
    Returns:
    ensemble key without a name
  - getZooKeeperClusterKey
```
public static String getZooKeeperClusterKey(org.apache.hadoop.conf.Configuration conf,
                            String name)
```
    Get the key to the ZK ensemble for this configuration and append a name at the end
    
    Parameters:
    conf - Configuration to use to build the key
    name - Name that should be appended at the end if not empty or null
    
    Returns:
    ensemble key with a name (if any)
  - standardizeZKQuorumServerString
```
public static String standardizeZKQuorumServerString(String quorumStringInput,
                                     String clientPort)
```
    Standardize the ZK quorum string: make it a "server:clientport" list, separated by ','
    
    Parameters:
    quorumStringInput - a string contains a list of servers for ZK quorum
    clientPort - the default client port
    
    Returns:
    the string for a list of "server:port" separated by ","

Class ZKConfig

Nested Class Summary

Method Summary

Methods inherited from class java.lang.Object

Method Detail

makeZKProps

parseZooCfg

getZKQuorumServersString

buildZKQuorumServerString

validateClusterKey

transformClusterKey

getZooKeeperClusterKey

getZooKeeperClusterKey

standardizeZKQuorumServerString