VinciContext (Apache UIMA Java SDK: uimaj 2.5.0 API)

java.lang.Object
- org.apache.vinci.transport.context.VinciContext

```
public class VinciContext
extends Object
```
This class can be used to globally affect various behaviors of Vinci clients and servers under its control (for example, which VNS to contact). There is one "global" VinciContext that is used by default, though anyone can create an alternate context should multiple sets of defaults be required in a single program. Each VinciContext also serves to cache resolve results for all clients under its control (for a default of 1 minute).

For the most part, Vinci library users won't have to directly deal with this class, since there is a global context used by default which is almost always adequate.

The most common use of this class is to programmatically specify a VNS hostname other than the default (which is the one specified by the Java property VNS_HOST).

Field Summary

Fields
Modifier and Type Field and Description

static int DEFAULT_VNS_CACHE_SIZE

Fields
Modifier and Type	Field and Description
`static int`	`DEFAULT_VNS_CACHE_SIZE`

Constructor Summary

Constructors
Constructor and Description

VinciContext(String myhost, int myport)

Constructors
Constructor and Description
`VinciContext(String myhost, int myport)`

Method Summary

Methods
Modifier and Type	Method and Description
`boolean`	`areStaleLookupsAllowed()` Returns whether clients can use stale resolve cache entries for service location in the event VNS is unreachable.
`void`	`cacheResolveResult(String serviceName, ResolveResult r)` Provide a resolve result to cache.
`void`	`flushAll()`
`void`	`flushFromCache(String serviceName)` Flush any cache entries pertaining to the specified service.
`ResolveResult`	`getCachedResolveResult(String serviceName)` Get a cached resolve result (if any).
`static VinciContext`	`getGlobalContext()` Get the global VinciContext used by Vinci classes when no context is explicitly specified.
`int`	`getResolveCacheTTL()` Get the time-to-live of cached service locators (resolve results).
`ResolveResult`	`getStaleCachedResolveResult(String serviceName)` Get a cached resolve result (if any), but allow returning stale cache entries.
`String`	`getVNSHost()` Return the VNS hostname.
`int`	`getVNSPort()` Return the VNS listener port.
`int`	`getVNSResolveTimeout()` Get the timeout setting of VNS resolve queries.
`int`	`getVNSServeonTimeout()` Get the timeout setting of VNS serveon queries.
`boolean`	`isSocketKeepAliveEnabled()` Returns whether socket keepAlive is enabled.
`VinciFrame`	`rpc(Transportable in, String service_name)` See documentation for VinciClient.rpc().
`VinciFrame`	`rpc(Transportable in, String service_name, int timeout)` See documentation for VinciClient.rpc().
`VinciFrame`	`rpc(Transportable in, String service_name, int socket_timeout, int connect_timeout)` See documentation for VinciClient.rpc().
`Transportable`	`sendAndReceive(Transportable in, String service_name, TransportableFactory factory)` See documentation for VinciClient.sendAndReceive().
`Transportable`	`sendAndReceive(Transportable in, String service_name, TransportableFactory factory, int socket_timeout)` See documentation for VinciClient.sendAndReceive().
`Transportable`	`sendAndReceive(Transportable in, String service_name, TransportableFactory factory, int socket_timeout, int connect_timeout)` See documentation for VinciClient.sendAndReceive().
`void`	`setAllowStaleLookups(boolean b)` Set whether clients can use stale resolve cache entries for service location in the event VNS is unreachable.
`void`	`setResolveCacheTTL(int millis)` Set the time-to-live of cached service locators (resolve results).
`void`	`setSocketKeepAliveEnabled(boolean b)` Set whether socket keepAlive is enabled.
`void`	`setVNSCacheSize(int to)` Set the size of the VNS cache.
`void`	`setVNSHost(String h)` Set the VNS hostname.
`void`	`setVNSPort(int p)` Set the VNS port.
`void`	`setVNSResolveTimeout(int millis)` Set the timeout of VNS resolve queries.
`void`	`setVNSServeonTimeout(int millis)` Set the timeout of VNS serveon queries.

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

- Field Detail
  - DEFAULT_VNS_CACHE_SIZE
```
public static final int DEFAULT_VNS_CACHE_SIZE
```
    See Also:
    Constant Field Values
- Constructor Detail
  - VinciContext
```
public VinciContext(String myhost,
            int myport)
```
- Method Detail
  - setVNSCacheSize
```
public void setVNSCacheSize(int to)
```
    Set the size of the VNS cache. This method can be invoked at any time, however if the cache size is ever reduced, it might not take effect.
    
    Parameters:
    to - The limit on the number of entries that will be maintained in the VNS cache.
  - getVNSHost
```
public String getVNSHost()
```
    Return the VNS hostname. When the global instance of this class is first loaded, it will set the hostname from the java property VNS_HOST. To set the VNS_HOST using this java property, you must therefore specify the property before the class is ever referenced, e.g. through the command-line property option -DVNS_HOST=[hostname], or by calling System.setProperty("VNS_HOST", [hostname]) before ever invoking any Vinci client code. Otherwise, you can set the hostname using the setVNSHost() method provided by this class.
    
    Throws:
    
    IllegalStateException - if the VNS host has not been specified.
  - getVNSPort
```
public int getVNSPort()
```
    Return the VNS listener port. When the global instance of this class is first loaded, it will attempt to set the port number from the java property VNS_PORT. To set the port using this java property, you must therefore specify the VNS_PORT property before the class is ever referenced, e.g. through the command-line property option -DVNS_PORT=[hostname], or by calling System.setProperty("VNS_PORT", [hostname]) before ever invoking any Vinci client code. Otherwise, the port will default to 9000. You can override this default (or any property-specified value) by calling the setPort() method provided by this class.
  - setVNSHost
```
public void setVNSHost(String h)
```
    Set the VNS hostname.
  - setVNSPort
```
public void setVNSPort(int p)
```
    Set the VNS port.
  - areStaleLookupsAllowed
```
public boolean areStaleLookupsAllowed()
```
    Returns whether clients can use stale resolve cache entries for service location in the event VNS is unreachable.
  - setAllowStaleLookups
```
public void setAllowStaleLookups(boolean b)
```
    Set whether clients can use stale resolve cache entries for service location in the event VNS is unreachable. Default is true.
  - getResolveCacheTTL
```
public int getResolveCacheTTL()
```
    Get the time-to-live of cached service locators (resolve results).
  - setResolveCacheTTL
```
public void setResolveCacheTTL(int millis)
```
    Set the time-to-live of cached service locators (resolve results). Default is 1 minute. Set to 0 to disable caching completely.
  - getVNSResolveTimeout
```
public int getVNSResolveTimeout()
```
    Get the timeout setting of VNS resolve queries.
  - setVNSResolveTimeout
```
public void setVNSResolveTimeout(int millis)
```
    Set the timeout of VNS resolve queries. Default is 20 seconds.
  - getVNSServeonTimeout
```
public int getVNSServeonTimeout()
```
    Get the timeout setting of VNS serveon queries.
  - setVNSServeonTimeout
```
public void setVNSServeonTimeout(int millis)
```
    Set the timeout of VNS serveon queries. Default is 60 seconds.
  - isSocketKeepAliveEnabled
```
public boolean isSocketKeepAliveEnabled()
```
    Returns whether socket keepAlive is enabled.
    
    See Also:
    Socket.setKeepAlive(boolean)
  - setSocketKeepAliveEnabled
```
public void setSocketKeepAliveEnabled(boolean b)
```
    Set whether socket keepAlive is enabled. Default is true.
    
    See Also:
    Socket.setKeepAlive(boolean)
  - getGlobalContext
```
public static VinciContext getGlobalContext()
```
    Get the global VinciContext used by Vinci classes when no context is explicitly specified.
  - getCachedResolveResult
```
public ResolveResult getCachedResolveResult(String serviceName)
```
    Get a cached resolve result (if any).
    
    Returns:
    the cached resolve result, or null if none is cached.
  - getStaleCachedResolveResult
```
public ResolveResult getStaleCachedResolveResult(String serviceName)
```
    Get a cached resolve result (if any), but allow returning stale cache entries.
    
    Returns:
    the cached resolve result, or null if none is cached.
  - cacheResolveResult
```
public void cacheResolveResult(String serviceName,
                      ResolveResult r)
```
    Provide a resolve result to cache.
  - flushFromCache
```
public void flushFromCache(String serviceName)
```
    Flush any cache entries pertaining to the specified service.
  - flushAll
```
public void flushAll()
```
  - sendAndReceive
```
public Transportable sendAndReceive(Transportable in,
                           String service_name,
                           TransportableFactory factory)
                             throws IOException,
                                    ServiceException,
                                    ServiceDownException,
                                    VNSException
```
    See documentation for VinciClient.sendAndReceive().
    
    Throws:
    
    IllegalStateException - if the VNS host has not been specified.
    
    IOException
    
    ServiceException
    
    ServiceDownException
    
    VNSException
    See Also:
    VinciClient
  - sendAndReceive
```
public Transportable sendAndReceive(Transportable in,
                           String service_name,
                           TransportableFactory factory,
                           int socket_timeout)
                             throws IOException,
                                    ServiceException
```
    See documentation for VinciClient.sendAndReceive().
    
    Throws:
    
    IllegalStateException - if the VNS host has not been specified.
    
    IOException
    
    ServiceException
    See Also:
    VinciClient
  - sendAndReceive
```
public Transportable sendAndReceive(Transportable in,
                           String service_name,
                           TransportableFactory factory,
                           int socket_timeout,
                           int connect_timeout)
                             throws IOException,
                                    ServiceException
```
    See documentation for VinciClient.sendAndReceive(). WARNING: This method relies on JDK-1.4 specific functions. USE IT ONLY if you don't need to maintain JDK1.3 compatability.
    
    Throws:
    
    IllegalStateException - if the VNS host has not been specified.
    
    IOException
    
    ServiceException
    See Also:
    VinciClient
  - rpc
```
public VinciFrame rpc(Transportable in,
             String service_name)
               throws IOException,
                      ServiceException,
                      ServiceDownException,
                      VNSException
```
    See documentation for VinciClient.rpc().
    
    Throws:
    
    IllegalStateException - if the VNS host has not been specified.
    
    IOException
    
    ServiceException
    
    ServiceDownException
    
    VNSException
    See Also:
    VinciClient
  - rpc
```
public VinciFrame rpc(Transportable in,
             String service_name,
             int timeout)
               throws IOException,
                      ServiceException,
                      ServiceDownException,
                      VNSException
```
    See documentation for VinciClient.rpc().
    
    Throws:
    
    IllegalStateException - if the VNS host has not been specified.
    
    IOException
    
    ServiceException
    
    ServiceDownException
    
    VNSException
    See Also:
    VinciClient
  - rpc
```
public VinciFrame rpc(Transportable in,
             String service_name,
             int socket_timeout,
             int connect_timeout)
               throws IOException,
                      ServiceException,
                      ServiceDownException,
                      VNSException
```
    See documentation for VinciClient.rpc(). WARNING: This method relies on JDK-1.4 specific functions. USE IT ONLY if you don't need to maintain JDK1.3 compatability.
    
    Throws:
    
    IllegalStateException - if the VNS host has not been specified.
    
    IOException
    
    ServiceException
    
    ServiceDownException
    
    VNSException
    See Also:
    VinciClient

Class VinciContext

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

DEFAULT_VNS_CACHE_SIZE

Constructor Detail

VinciContext

Method Detail

setVNSCacheSize

getVNSHost

getVNSPort

setVNSHost

setVNSPort

areStaleLookupsAllowed

setAllowStaleLookups

getResolveCacheTTL

setResolveCacheTTL

getVNSResolveTimeout

setVNSResolveTimeout

getVNSServeonTimeout

setVNSServeonTimeout

isSocketKeepAliveEnabled

setSocketKeepAliveEnabled

getGlobalContext

getCachedResolveResult

getStaleCachedResolveResult

cacheResolveResult

flushFromCache

flushAll

sendAndReceive

sendAndReceive

sendAndReceive

rpc

rpc

rpc