BaseViewChecker (Apache Sling 9 API)

java.lang.Object
- org.apache.sling.discovery.base.commons.BaseViewChecker

All Implemented Interfaces:

Runnable, ViewChecker

Direct Known Subclasses:

OakViewChecker
```
public abstract class BaseViewChecker
extends Object
implements ViewChecker, Runnable
```
The heartbeat handler is responsible and capable of issuing both local and remote heartbeats and registers a periodic job with the scheduler for doing so.
Local heartbeats are stored in the repository. Remote heartbeats are POSTs to remote TopologyConnectorServlets.

Field Summary

Fields
Modifier and Type	Field and Description
`protected boolean`	`activated` SLING-2895: avoid heartbeats after deactivation
`protected org.osgi.service.component.ComponentContext`	`context` keep a reference to the component context
`protected Map<Long,String[]>`	`endpoints` SLING-4765 : store endpoints to /clusterInstances for more verbose duplicate slingId/ghost detection
`protected Object`	`lock` lock object for synchronizing the run method
`protected org.slf4j.Logger`	`logger`
`protected String`	`NAME` the name used for the period job with the scheduler
`protected PeriodicBackgroundJob`	`periodicPingJob`
`protected static String`	`PROPERTY_ID_ENDPOINTS`
`protected static String`	`PROPERTY_ID_RUNTIME`
`protected static String`	`PROPERTY_ID_SLING_HOME_PATH`
`protected String`	`runtimeId` SLING-2901: the runtimeId is a unique id, set on activation, used for robust duplicate sling.id detection
`protected String`	`slingId` the sling id of the local instance

Constructor Summary

Constructors
Constructor and Description

BaseViewChecker()

Constructors
Constructor and Description
`BaseViewChecker()`

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`protected void`	`activate(org.osgi.service.component.ComponentContext context)`
`protected void`	`bindHttpService(org.osgi.framework.ServiceReference reference)` Bind a http service
`void`	`checkView()` for testing only
`protected void`	`deactivate()`
`protected void`	`doActivate()`
`protected void`	`doCheckView()` Check whether the established view matches the reality, ie matches the heartbeats
`protected abstract AnnouncementRegistry`	`getAnnouncementRegistry()`
`protected abstract BaseConfig`	`getConnectorConfig()`
`protected abstract ConnectorRegistry`	`getConnectorRegistry()`
`protected String`	`getEndpointsAsString()`
`protected abstract ResourceResolverFactory`	`getResourceResolverFactory()`
`protected abstract Scheduler`	`getScheduler()`
`protected abstract SlingSettingsService`	`getSlingSettingsService()`
`void`	`heartbeatAndCheckView()` Issue a heartbeat and check the view
`protected void`	`issueConnectorPings()` Issue a remote heartbeat using the topology connectors
`protected void`	`issueHeartbeat()` Issue a heartbeat.
`void`	`run()`
`void`	`triggerAsyncConnectorPing()` Trigger the issuance of the next heartbeat asap instead of at next heartbeat interval
`protected void`	`unbindHttpService(org.osgi.framework.ServiceReference reference)` Unbind a http service
`protected abstract void`	`updateProperties()`

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

- Field Detail
  - logger
```
protected final org.slf4j.Logger logger
```
  - PROPERTY_ID_ENDPOINTS
```
protected static final String PROPERTY_ID_ENDPOINTS
```
    See Also:
    
    Constant Field Values
  - PROPERTY_ID_SLING_HOME_PATH
```
protected static final String PROPERTY_ID_SLING_HOME_PATH
```
    See Also:
    
    Constant Field Values
  - PROPERTY_ID_RUNTIME
```
protected static final String PROPERTY_ID_RUNTIME
```
    See Also:
    
    Constant Field Values
  - NAME
```
protected String NAME
```
    the name used for the period job with the scheduler
  - slingId
```
protected String slingId
```
    the sling id of the local instance
  - runtimeId
```
protected String runtimeId
```
    SLING-2901: the runtimeId is a unique id, set on activation, used for robust duplicate sling.id detection
  - lock
```
protected final Object lock
```
    lock object for synchronizing the run method
  - activated
```
protected volatile boolean activated
```
    SLING-2895: avoid heartbeats after deactivation
  - context
```
protected org.osgi.service.component.ComponentContext context
```
    keep a reference to the component context
  - endpoints
```
protected final Map<Long,String[]> endpoints
```
    SLING-4765 : store endpoints to /clusterInstances for more verbose duplicate slingId/ghost detection
  - periodicPingJob
```
protected PeriodicBackgroundJob periodicPingJob
```
- Constructor Detail
  - BaseViewChecker
```
public BaseViewChecker()
```
- Method Detail
  - getSlingSettingsService
```
protected abstract SlingSettingsService getSlingSettingsService()
```
  - getResourceResolverFactory
```
protected abstract ResourceResolverFactory getResourceResolverFactory()
```
  - getConnectorRegistry
```
protected abstract ConnectorRegistry getConnectorRegistry()
```
  - getAnnouncementRegistry
```
protected abstract AnnouncementRegistry getAnnouncementRegistry()
```
  - getScheduler
```
protected abstract Scheduler getScheduler()
```
  - getConnectorConfig
```
protected abstract BaseConfig getConnectorConfig()
```
  - activate
```
@Activate
protected void activate(org.osgi.service.component.ComponentContext context)
```
  - doActivate
```
protected void doActivate()
```
  - deactivate
```
@Deactivate
protected void deactivate()
```
  - checkView
```
public void checkView()
```
    for testing only
    
    Specified by:
    
    checkView in interface ViewChecker
  - run
```
public void run()
```
    Specified by:
    
    run in interface Runnable
  - heartbeatAndCheckView
```
public void heartbeatAndCheckView()
```
    Description copied from interface: ViewChecker
    
    Issue a heartbeat and check the view
    
    Specified by:
    
    heartbeatAndCheckView in interface ViewChecker
  - triggerAsyncConnectorPing
```
public void triggerAsyncConnectorPing()
```
    Trigger the issuance of the next heartbeat asap instead of at next heartbeat interval
  - issueHeartbeat
```
protected void issueHeartbeat()
```
    Issue a heartbeat.
    This action consists of first updating the local properties, then issuing a cluster-local heartbeat (within the repository) and then a remote heartbeat (to all the topology connectors which announce this part of the topology to others)
  - updateProperties
```
protected abstract void updateProperties()
```
  - issueConnectorPings
```
protected void issueConnectorPings()
```
    Issue a remote heartbeat using the topology connectors
  - doCheckView
```
protected void doCheckView()
```
    Check whether the established view matches the reality, ie matches the heartbeats
  - bindHttpService
```
protected void bindHttpService(org.osgi.framework.ServiceReference reference)
```
    Bind a http service
  - unbindHttpService
```
protected void unbindHttpService(org.osgi.framework.ServiceReference reference)
```
    Unbind a http service
  - getEndpointsAsString
```
protected String getEndpointsAsString()
```

Class BaseViewChecker

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

logger

PROPERTY_ID_ENDPOINTS

PROPERTY_ID_SLING_HOME_PATH

PROPERTY_ID_RUNTIME

NAME

slingId

runtimeId

lock

activated

context

endpoints

periodicPingJob

Constructor Detail

BaseViewChecker

Method Detail

getSlingSettingsService

getResourceResolverFactory

getConnectorRegistry

getAnnouncementRegistry

getScheduler

getConnectorConfig

activate

doActivate

deactivate

checkView

run

heartbeatAndCheckView

triggerAsyncConnectorPing

issueHeartbeat

updateProperties

issueConnectorPings

doCheckView

bindHttpService

unbindHttpService

getEndpointsAsString