Package com.sun.enterprise.ee.cms.impl.base

Class GroupHandleImpl

  • All Implemented Interfaces:
    com.sun.enterprise.ee.cms.core.GroupHandle
    public final class GroupHandleImpl
extends java.lang.Object
implements com.sun.enterprise.ee.cms.core.GroupHandle
    Implementation of GroupHandle interface.
    Version:
    $Revision$
    Author:
    Shreedhar Ganapathy Date: Jan 12, 2004

    • Constructor Summary

      Constructors 
      Constructor Description
      GroupHandleImpl​(java.lang.String groupName, java.lang.String serverToken)  

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void announceWatchdogObservedFailure​(java.lang.String serverToken)  
      java.util.List<java.lang.String> getAllCurrentMembers()
      returns a List containing the current group membership including spectator members.
      java.util.List<java.lang.String> getAllCurrentMembersWithStartTimes()  
      com.sun.enterprise.ee.cms.core.AliveAndReadyView getCurrentAliveAndReadyCoreView()  
      java.util.List<java.lang.String> getCurrentAliveOrReadyMembers()  
      java.util.List<java.lang.String> getCurrentCoreMembers()
      returns a List containing the current core members in the group.
      java.util.List<java.lang.String> getCurrentCoreMembersWithStartTimes()  
      java.util.List<com.sun.enterprise.ee.cms.core.GMSMember> getCurrentView()  
      com.sun.enterprise.ee.cms.core.DistributedStateCache getDistributedStateCache()
      returns a DistributedStateCache object that provides the ability to set and retrieve CachedStates.
      java.lang.String getGroupLeader()  
      com.sun.enterprise.ee.cms.spi.MemberStates getMemberState​(java.lang.String member)  
      com.sun.enterprise.ee.cms.spi.MemberStates getMemberState​(java.lang.String member, long threshold, long timeout)  
      com.sun.enterprise.ee.cms.core.AliveAndReadyView getPreviousAliveAndReadyCoreView()  
      java.util.List<com.sun.enterprise.ee.cms.core.GMSMember> getPreviousView()  
      java.util.List<java.lang.String> getSuspectList()  
      boolean isFenced​(java.lang.String componentName, java.lang.String memberToken)
      Provides the status of a member component's fence, if any.
      boolean isGroupLeader()  
      boolean isMemberAlive​(java.lang.String memberToken)  
      boolean isWatchdog()  
      void lowerFence​(java.lang.String componentName, java.lang.String failedMemberToken)
      Enables the caller to lower a logical fence that was earlier raised on a target member component.
      void raiseFence​(java.lang.String componentName, java.lang.String failedMemberToken)
      Enables the caller to raise a logical fence on a specified target member token's component.
      void removeRecoveryAppointments​(java.lang.String failedMemberToken, java.lang.String componentName)  
      void sendMessage​(java.lang.String componentName, byte[] message)
      Sends a message to all members of the Group.
      void sendMessage​(java.lang.String targetServerToken, java.lang.String targetComponentName, byte[] message)
      Sends a message to a single member of the group Expects a targetServerToken representing the recipient member's id, the target component name in the target recipient member, and a byte array as parameter carrying the payload.
      void sendMessage​(java.util.List<java.lang.String> targetServerTokens, java.lang.String targetComponentName, byte[] message)  
      java.lang.String toString()  

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

    • Constructor Detail

      • GroupHandleImpl

        public GroupHandleImpl​(java.lang.String groupName,
                       java.lang.String serverToken)

    • Method Detail

      • sendMessage

        public void sendMessage​(java.lang.String componentName,
                        byte[] message)
                 throws com.sun.enterprise.ee.cms.core.GMSException
        Sends a message to all members of the Group. Expects a byte array as parameter carrying the payload.
        Specified by:
        sendMessage in interface com.sun.enterprise.ee.cms.core.GroupHandle
        Parameters:
        componentName - Destination component in remote members.
        message - Payload in byte array to be delivered to the destination.
        Throws:
        com.sun.enterprise.ee.cms.core.GMSException

      • sendMessage

        public void sendMessage​(java.lang.String targetServerToken,
                        java.lang.String targetComponentName,
                        byte[] message)
                 throws com.sun.enterprise.ee.cms.core.GMSException
        Sends a message to a single member of the group Expects a targetServerToken representing the recipient member's id, the target component name in the target recipient member, and a byte array as parameter carrying the payload. Specifying a null component name would result in the message being delivered to all registered components in the target member instance.
        Specified by:
        sendMessage in interface com.sun.enterprise.ee.cms.core.GroupHandle
        Parameters:
        targetServerToken - destination member's identification
        targetComponentName - destination member's target component
        message - Payload in byte array to be delivered to the destination.
        Throws:
        com.sun.enterprise.ee.cms.core.GMSException

      • sendMessage

        public void sendMessage​(java.util.List<java.lang.String> targetServerTokens,
                        java.lang.String targetComponentName,
                        byte[] message)
                 throws com.sun.enterprise.ee.cms.core.GMSException
        Specified by:
        sendMessage in interface com.sun.enterprise.ee.cms.core.GroupHandle
        Throws:
        com.sun.enterprise.ee.cms.core.GMSException

      • getDistributedStateCache

        public com.sun.enterprise.ee.cms.core.DistributedStateCache getDistributedStateCache()
        returns a DistributedStateCache object that provides the ability to set and retrieve CachedStates.
        Specified by:
        getDistributedStateCache in interface com.sun.enterprise.ee.cms.core.GroupHandle
        Returns:
        DistributedStateCache
        See Also:
        DistributedStateCache

      • getCurrentCoreMembers

        public java.util.List<java.lang.String> getCurrentCoreMembers()
        returns a List containing the current core members in the group.
        Specified by:
        getCurrentCoreMembers in interface com.sun.enterprise.ee.cms.core.GroupHandle
        Returns:
        List a List of member token ids pertaining to core members

      • getAllCurrentMembers

        public java.util.List<java.lang.String> getAllCurrentMembers()
        returns a List containing the current group membership including spectator members.
        Specified by:
        getAllCurrentMembers in interface com.sun.enterprise.ee.cms.core.GroupHandle
        Returns:
        List a List of member token ids pertaining to all members

      • getCurrentCoreMembersWithStartTimes

        public java.util.List<java.lang.String> getCurrentCoreMembersWithStartTimes()
        Specified by:
        getCurrentCoreMembersWithStartTimes in interface com.sun.enterprise.ee.cms.core.GroupHandle

      • getAllCurrentMembersWithStartTimes

        public java.util.List<java.lang.String> getAllCurrentMembersWithStartTimes()
        Specified by:
        getAllCurrentMembersWithStartTimes in interface com.sun.enterprise.ee.cms.core.GroupHandle

      • raiseFence

        public void raiseFence​(java.lang.String componentName,
                       java.lang.String failedMemberToken)
                throws com.sun.enterprise.ee.cms.core.GMSException
        Enables the caller to raise a logical fence on a specified target member token's component. This API is directly called only when a component is raising a fence itself and not as part of acquiring a signal. If this is part of acquiring a signal, then the call should be to signal.acquire() which encompasses raising a fence and potentially other state updates.

        Failure Fencing is a group-wide protocol that, on one hand, requires members to update a shared/distributed datastructure if any of their components need to perform operations on another members' corresponding component. On the other hand, the group-wide protocol requires members to observe "Netiquette" during their startup so as to check if any of their components are being operated upon by other group members. Typically this check is performed by the respective components themselves. See the isFenced() method below for this check. When the operation is completed by the remote member component, it removes the entry from the shared datastructure. See the lowerFence() method below.

        Raising the fence, places an entry into a distributed datastructure that is accessed by other members during their startup

        Specified by:
        raiseFence in interface com.sun.enterprise.ee.cms.core.GroupHandle
        Parameters:
        componentName - the component name
        failedMemberToken - the member token
        Throws:
        com.sun.enterprise.ee.cms.core.GMSException - the GMS generic exception

      • lowerFence

        public void lowerFence​(java.lang.String componentName,
                       java.lang.String failedMemberToken)
                throws com.sun.enterprise.ee.cms.core.GMSException
        Enables the caller to lower a logical fence that was earlier raised on a target member component. This is typically done when the operation being performed on the target member component has now completed. This api is directly called only by a component that is lowering a fence directly and not as part of releasing a signal. If the operation is to release a signal, then the appropriate call is to signal.release() which encompasses lowering the fence and other cleanups.
        Specified by:
        lowerFence in interface com.sun.enterprise.ee.cms.core.GroupHandle
        Parameters:
        componentName - target member component
        failedMemberToken - the member token of the failed member
        Throws:
        com.sun.enterprise.ee.cms.core.GMSException - the GMS Generic Exception

      • removeRecoveryAppointments

        public void removeRecoveryAppointments​(java.lang.String failedMemberToken,
                                       java.lang.String componentName)
                                throws com.sun.enterprise.ee.cms.core.GMSException
        Specified by:
        removeRecoveryAppointments in interface com.sun.enterprise.ee.cms.core.GroupHandle
        Throws:
        com.sun.enterprise.ee.cms.core.GMSException

      • isFenced

        public boolean isFenced​(java.lang.String componentName,
                        java.lang.String memberToken)
        Provides the status of a member component's fence, if any.

        This check is mandatorily done at the time a member component is in the process of starting(note that at this point we assume that this member failed in its previous lifetime).

        The boolean value returned would indicate if this member component is being recovered by any other member. The criteria for returning a boolean "true" is that this componentName-memberToken combo is present as a value for any key in the GMS DistributedStateCache. If a true is returned, for instance, this could mean that the client component should continue its startup without attempting to perform its own recovery operations.

        The criteria for returning a boolean "false" is that the componentId-memberTokenId combo is not present in the list of values in the DistributedStateCache.If a boolean "false" is returned, this could mean that the client component can continue with its lifecycle startup per its normal startup policies.

        Specified by:
        isFenced in interface com.sun.enterprise.ee.cms.core.GroupHandle
        Parameters:
        componentName - the component name
        memberToken - the member token
        Returns:
        boolean

      • isMemberAlive

        public boolean isMemberAlive​(java.lang.String memberToken)
        Specified by:
        isMemberAlive in interface com.sun.enterprise.ee.cms.core.GroupHandle

      • getGroupLeader

        public java.lang.String getGroupLeader()
        Specified by:
        getGroupLeader in interface com.sun.enterprise.ee.cms.core.GroupHandle

      • isGroupLeader

        public boolean isGroupLeader()
        Specified by:
        isGroupLeader in interface com.sun.enterprise.ee.cms.core.GroupHandle

      • getSuspectList

        public java.util.List<java.lang.String> getSuspectList()

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object

      • getCurrentAliveOrReadyMembers

        public java.util.List<java.lang.String> getCurrentAliveOrReadyMembers()
        Specified by:
        getCurrentAliveOrReadyMembers in interface com.sun.enterprise.ee.cms.core.GroupHandle

      • getMemberState

        public com.sun.enterprise.ee.cms.spi.MemberStates getMemberState​(java.lang.String member)
        Specified by:
        getMemberState in interface com.sun.enterprise.ee.cms.core.GroupHandle

      • getMemberState

        public com.sun.enterprise.ee.cms.spi.MemberStates getMemberState​(java.lang.String member,
                                                                 long threshold,
                                                                 long timeout)
        Specified by:
        getMemberState in interface com.sun.enterprise.ee.cms.core.GroupHandle

      • isWatchdog

        public boolean isWatchdog()

      • announceWatchdogObservedFailure

        public void announceWatchdogObservedFailure​(java.lang.String serverToken)
                                     throws com.sun.enterprise.ee.cms.core.GMSException
        Specified by:
        announceWatchdogObservedFailure in interface com.sun.enterprise.ee.cms.core.GroupHandle
        Throws:
        com.sun.enterprise.ee.cms.core.GMSException

      • getCurrentView

        public java.util.List<com.sun.enterprise.ee.cms.core.GMSMember> getCurrentView()
        Specified by:
        getCurrentView in interface com.sun.enterprise.ee.cms.core.GroupHandle

      • getPreviousView

        public java.util.List<com.sun.enterprise.ee.cms.core.GMSMember> getPreviousView()
        Specified by:
        getPreviousView in interface com.sun.enterprise.ee.cms.core.GroupHandle

      • getPreviousAliveAndReadyCoreView

        public com.sun.enterprise.ee.cms.core.AliveAndReadyView getPreviousAliveAndReadyCoreView()
        Specified by:
        getPreviousAliveAndReadyCoreView in interface com.sun.enterprise.ee.cms.core.GroupHandle

      • getCurrentAliveAndReadyCoreView

        public com.sun.enterprise.ee.cms.core.AliveAndReadyView getCurrentAliveAndReadyCoreView()
        Specified by:
        getCurrentAliveAndReadyCoreView in interface com.sun.enterprise.ee.cms.core.GroupHandle