Package org.apache.geode.cache.execute

Class FunctionService

java.lang.Object
org.apache.geode.cache.execute.FunctionService
public class FunctionService extends Object
Provides the entry point into execution of user defined Functions.

Function execution provides a means to route application behaviour to data or more generically to peers in a DistributedSystem or servers in a Pool.

Since:
GemFire 6.0

  • Constructor Details

    • FunctionService

      protected FunctionService(org.apache.geode.internal.cache.execute.FunctionExecutionService functionExecutionService)

  • Method Details

    • onRegion

      public static Execution onRegion(Region region)
      Returns an Execution object that can be used to execute a data dependent function on the specified Region.
      When invoked from a GemFire client, the method returns an Execution instance that sends a message to one of the connected servers as specified by the Pool for the region.
      Depending on the filters setup on the Execution, the function is executed on all GemFire members that define the data region, or a subset of members. Execution.withFilter(Set)). For DistributedRegions with DataPolicy.NORMAL, it throws UnsupportedOperationException. For DistributedRegions with DataPolicy.EMPTY, execute the function on any random member which has DataPolicy.REPLICATE
      . For DistributedRegions with DataPolicy.REPLICATE, execute the function locally. For Regions with DataPolicy.PARTITION, it executes on members where the data resides as specified by the filter.
      Parameters:
      region - the Region on which the returned Execution will execute functions
      Returns:
      an Execution object that can be used to execute a data dependent function on the specified Region
      Throws:
      FunctionException - if the region passed in is null
      Since:
      GemFire 6.0

    • onServer

      public static Execution onServer(Pool pool)
      Returns an Execution object that can be used to execute a data independent function on a server in the provided Pool.

      If the server goes down while dispatching or executing the function, an Exception will be thrown.

      Parameters:
      pool - from which to chose a server for execution
      Returns:
      an Execution object that can be used to execute a data independent function on a server in the provided Pool
      Throws:
      FunctionException - if Pool instance passed in is null
      Since:
      GemFire 6.0

    • onServers

      public static Execution onServers(Pool pool)
      Returns an Execution object that can be used to execute a data independent function on all the servers in the provided Pool. If one of the servers goes down while dispatching or executing the function on the server, an Exception will be thrown.
      Parameters:
      pool - the set of servers to execute the function
      Returns:
      an Execution object that can be used to execute a data independent function on all the servers in the provided Pool
      Throws:
      FunctionException - if Pool instance passed in is null
      Since:
      GemFire 6.0

    • onServer

      public static Execution onServer(RegionService regionService)
      Returns an Execution object that can be used to execute a data independent function on a server that the given cache is connected to.

      If the server goes down while dispatching or executing the function, an Exception will be thrown.

      Parameters:
      regionService - obtained from ClientCacheFactory.create() or ClientCache.createAuthenticatedView(Properties).
      Returns:
      an Execution object that can be used to execute a data independent function on a server that the given cache is connected to
      Throws:
      FunctionException - if cache is null, is not on a client, or it does not have a default pool
      Since:
      GemFire 6.5

    • onServers

      public static Execution onServers(RegionService regionService)
      Returns an Execution object that can be used to execute a data independent function on all the servers that the given cache is connected to. If one of the servers goes down while dispatching or executing the function on the server, an Exception will be thrown.
      Parameters:
      regionService - obtained from ClientCacheFactory.create() or ClientCache.createAuthenticatedView(Properties).
      Returns:
      an Execution object that can be used to execute a data independent function on all the servers that the given cache is connected to
      Throws:
      FunctionException - if cache is null, is not on a client, or it does not have a default pool
      Since:
      GemFire 6.5

    • onMember

      public static Execution onMember(DistributedMember distributedMember)
      Returns an Execution object that can be used to execute a data independent function on a DistributedMember. If the member is not found, executing the function will throw an Exception. If the member goes down while dispatching or executing the function on the member, an Exception will be thrown.
      Parameters:
      distributedMember - defines a member in the distributed system
      Returns:
      an Execution object that can be used to execute a data independent function on a DistributedMember
      Throws:
      FunctionException - if distributedMember is null
      Since:
      GemFire 7.0

    • onMembers

      public static Execution onMembers(String... groups)
      Returns an Execution object that can be used to execute a data independent function on all peer members. If the optional groups parameter is provided, function is executed on all members that belong to the provided groups.

      If one of the members goes down while dispatching or executing the function on the member, an Exception will be thrown.

      Parameters:
      groups - optional list of GemFire configuration property "groups" (see groups) on which to execute the function. Function will be executed on all members of each group
      Returns:
      an Execution object that can be used to execute a data independent function on all peer members
      Throws:
      FunctionException - if no members are found belonging to the provided groups
      Since:
      GemFire 7.0

    • onMembers

      public static Execution onMembers(Set<DistributedMember> distributedMembers)
      Returns an Execution object that can be used to execute a data independent function on the set of DistributedMembers. If one of the members goes down while dispatching or executing the function, an Exception will be thrown.
      Parameters:
      distributedMembers - set of distributed members on which Function to be executed
      Returns:
      an Execution object that can be used to execute a data independent function on the set of DistributedMembers provided
      Throws:
      FunctionException - if distributedMembers is null
      Since:
      GemFire 7.0

    • onMember

      public static Execution onMember(String... groups)
      Returns an Execution object that can be used to execute a data independent function on one member of each group provided.
      Parameters:
      groups - list of GemFire configuration property "groups" (see groups) on which to execute the function. Function will be executed on one member of each group
      Returns:
      an Execution object that can be used to execute a data independent function on one member of each group provided
      Throws:
      FunctionException - if no members are found belonging to the provided groups
      Since:
      GemFire 7.0

    • getFunction

      public static Function getFunction(String functionId)
      Returns the Function defined by the functionId, returns null if no function is found for the specified functionId
      Parameters:
      functionId - a functionId
      Returns:
      the Function defined by the functionId or null if no function is found for the specified functionId
      Throws:
      FunctionException - if functionID passed is null
      Since:
      GemFire 6.0

    • registerFunction

      public static void registerFunction(Function function)
      Registers the given Function with the FunctionService using Function.getId().

      Registering a function allows execution of the function using Execution.execute(String). Every member that could execute a function using its Function.getId() should register the function.

      Parameters:
      function - the Function to register
      Throws:
      FunctionException - if function instance passed is null or Function.getId() returns null
      Since:
      GemFire 6.0

    • unregisterFunction

      public static void unregisterFunction(String functionId)
      Unregisters the given Function with the FunctionService using Function.getId().

      Parameters:
      functionId - the ID of the function
      Throws:
      FunctionException - if function instance passed is null or Function.getId() returns null
      Since:
      GemFire 6.0

    • isRegistered

      public static boolean isRegistered(String functionId)
      Returns true if the function is registered to FunctionService
      Parameters:
      functionId - the ID of the function
      Returns:
      whether the function is registered to FunctionService
      Throws:
      FunctionException - if function instance passed is null or Function.getId() returns null
      Since:
      GemFire 6.0

    • getRegisteredFunctions

      public static Map<String,Function> getRegisteredFunctions()
      Returns all locally registered functions
      Returns:
      A view of registered functions as a Map of Function.getId() to Function
      Since:
      GemFire 6.0