VisibilityLabelsCache (Apache HBase 1.4.11 API)

java.lang.Object
- org.apache.hadoop.hbase.security.visibility.VisibilityLabelsCache

All Implemented Interfaces:

VisibilityLabelOrdinalProvider
```
@InterfaceAudience.Private
public class VisibilityLabelsCache
extends Object
implements VisibilityLabelOrdinalProvider
```
Maintains the cache for visibility labels and also uses the zookeeper to update the labels in the system. The cache updation happens based on the data change event that happens on the zookeeper znode for labels table

Method Summary

Methods
Modifier and Type	Method and Description
`static VisibilityLabelsCache`	`createAndGet(ZooKeeperWatcher watcher, org.apache.hadoop.conf.Configuration conf)` Creates the singleton instance, if not yet present, and returns the same.
`static VisibilityLabelsCache`	`get()`
`List<String>`	`getGroupAuths(String[] groups)`
`Set<Integer>`	`getGroupAuthsAsOrdinals(String[] groups)` Returns the list of ordinals of labels associated with the groups
`String`	`getLabel(int ordinal)` Returns the string associated with the ordinal.
`int`	`getLabelOrdinal(String label)`
`int`	`getLabelsCount()`
`List<String>`	`getUserAuths(String user)`
`Set<Integer>`	`getUserAuthsAsOrdinals(String user)` Returns the list of ordinals of labels associated with the user
`void`	`refreshLabelsCache(byte[] data)`
`void`	`refreshUserAuthsCache(byte[] data)`
`void`	`writeToZookeeper(byte[] data, boolean labelsOrUserAuths)`

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

- Method Detail
  - createAndGet
```
public static VisibilityLabelsCache createAndGet(ZooKeeperWatcher watcher,
                                 org.apache.hadoop.conf.Configuration conf)
                                          throws IOException
```
    Creates the singleton instance, if not yet present, and returns the same.
    
    Parameters:
    watcher -
    conf -
    
    Returns:
    Singleton instance of VisibilityLabelsCache
    
    Throws:
    
    IOException
  - get
```
public static VisibilityLabelsCache get()
```
    Returns:
    Singleton instance of VisibilityLabelsCache
    
    Throws:
    
    IllegalStateException - when this is called before calling createAndGet(ZooKeeperWatcher, Configuration)
  - refreshLabelsCache
```
public void refreshLabelsCache(byte[] data)
                        throws IOException
```
    Throws:
    
    IOException
  - refreshUserAuthsCache
```
public void refreshUserAuthsCache(byte[] data)
                           throws IOException
```
    Throws:
    
    IOException
  - getLabelOrdinal
```
public int getLabelOrdinal(String label)
```
    Specified by:
    
    getLabelOrdinal in interface VisibilityLabelOrdinalProvider
    
    Parameters:
    label - Not null label string
    
    Returns:
    The ordinal for the label. The ordinal starts from 1. Returns 0 when passed a non existing label.
  - getLabel
```
public String getLabel(int ordinal)
```
    Description copied from interface: VisibilityLabelOrdinalProvider
    
    Returns the string associated with the ordinal. Not be used in MR.
    
    Specified by:
    
    getLabel in interface VisibilityLabelOrdinalProvider
    
    Parameters:
    ordinal - The ordinal of label which we are looking for.
    
    Returns:
    The label having the given ordinal. Returns null when no label exist in the system with given ordinal
  - getLabelsCount
```
public int getLabelsCount()
```
    Returns:
    The total number of visibility labels.
  - getUserAuths
```
public List<String> getUserAuths(String user)
```
  - getGroupAuths
```
public List<String> getGroupAuths(String[] groups)
```
  - getUserAuthsAsOrdinals
```
public Set<Integer> getUserAuthsAsOrdinals(String user)
```
    Returns the list of ordinals of labels associated with the user
    
    Parameters:
    user - Not null value.
    
    Returns:
    the list of ordinals
  - getGroupAuthsAsOrdinals
```
public Set<Integer> getGroupAuthsAsOrdinals(String[] groups)
```
    Returns the list of ordinals of labels associated with the groups
    
    Parameters:
    groups -
    
    Returns:
    the list of ordinals
  - writeToZookeeper
```
public void writeToZookeeper(byte[] data,
                    boolean labelsOrUserAuths)
                      throws IOException
```
    Throws:
    
    IOException

Class VisibilityLabelsCache

Method Summary

Methods inherited from class java.lang.Object

Method Detail

createAndGet

get

refreshLabelsCache

refreshUserAuthsCache

getLabelOrdinal

getLabel

getLabelsCount

getUserAuths

getGroupAuths

getUserAuthsAsOrdinals

getGroupAuthsAsOrdinals

writeToZookeeper