Package com.ibm.websphere.command

Class CacheableCommandImpl

java.lang.Object
com.ibm.websphere.command.TargetableCommandImpl
com.ibm.websphere.command.CacheableCommandImpl
All Implemented Interfaces:
com.ibm.websphere.cache.Sizeable, CacheableCommand, Command, CommandCaller, TargetableCommand, Serializable
Direct Known Subclasses:
CacheableCommandImpl
public abstract class CacheableCommandImpl extends TargetableCommandImpl implements CacheableCommand, com.ibm.websphere.cache.Sizeable
This CacheableCommandImpl abstract class provides an implementation for all CacheableCommand interface methods except those that the command writer must write. This class provides a runtime for command execution that interacts with the CommandCache. It also provides the contract between this command runtime and the command writer.

CacheableCommandImpl is a super class of all CacheableCommands.

See Also:

  • Constructor Details

    • CacheableCommandImpl

      public CacheableCommandImpl()

  • Method Details

    • getId

      public final String getId()
      This is the method in the CacheableCommand interface. This must be implemented by the command writer.
      Specified by:
      getId in interface CacheableCommand
      Returns:
      The cache id.

    • getSharingPolicy

      public final int getSharingPolicy()
      This is the method in the CacheableCommand interface. This should be implemented by the command writer only if the default of EntryInfo.SHARED_PULL is not desired.
      Specified by:
      getSharingPolicy in interface CacheableCommand
      Returns:
      The sharing policy id.

    • preExecute

      public boolean preExecute()
      This implements the CacheableCommand interface. This should be implemented by the command writer only if there is something that needs to be done prior to executing the command on the server.
      Specified by:
      preExecute in interface CacheableCommand
      Returns:
      True implies that the command's execution should be terminated, so the performExecute, postExecute and setCommand will not happen.

    • postExecute

      public void postExecute()
      Implements the CacheableCommand interface. This should be implemented by the command writer only if there is something that needs to be done after executing the command on the server.
      Specified by:
      postExecute in interface CacheableCommand

    • execute

      public void execute() throws CommandException
      This implements the method in the Command interface, overriding the implementation in TargetableCommandImpl.

      It does the following:

      • Throws an UnsetInputPropertiesException if this command's isReadyToCallExecute method returns false.
      • Get the CommandTarget for this command from the targetPolicy.
      • If it is cached, return the cached command. The command may be cached locally or in the coordinator for the command.
      • If it is not cached, call the CommandTargetProxy.executeCommand method to execute the command, which calls the TargetableCommand.performExecute method, and cache it. The command may be run locally or in the coordinator for the command. The command may be cached after execution, depending on the sharing policy.
      • If the hasOutputProperties method returns true and the returned command is not the same instance as this command, it calls the setOutputProperties method so that the results will be copied into this command.
      • Set the time of execution of the command.
      Specified by:
      execute in interface Command
      Overrides:
      execute in class TargetableCommandImpl
      Throws:
      CommandException - The superclass for all command exceptions.

    • setCaller

      public void setCaller(CommandCaller caller)
      Implements the CacheableCommand interface method.
      Specified by:
      setCaller in interface CacheableCommand
      Parameters:
      caller - The command that called this command.

    • getCaller

      public CommandCaller getCaller()
      Implements the CacheableCommand interface method.
      Specified by:
      getCaller in interface CacheableCommand
      Returns:
      The caller of the command.

    • unionDependencies

      public void unionDependencies(com.ibm.websphere.cache.EntryInfo entryInfo)
      This is called by the CommandCache to add dependencies to this command.
      Specified by:
      unionDependencies in interface CommandCaller
      Parameters:
      entryInfo - This command's entryInfo.

    • getEntryInfo

      public com.ibm.websphere.cache.EntryInfo getEntryInfo()
      The gets this command's EntryInfo object, which holds its caching metadata.
      Specified by:
      getEntryInfo in interface CacheableCommand
      Returns:
      The EntryInfo object.

    • reset

      public void reset()
      Reset the command for reuse.
      Specified by:
      reset in interface Command
      Specified by:
      reset in class TargetableCommandImpl

    • executeFromCache

      public boolean executeFromCache() throws CommandException
      executeFromCache This method will check the cache to see if the given command is present. If so then the command is populated with the cached results and true is returned. If the command is not cached, then false is returned and no change is made to the state of the command.
      Specified by:
      executeFromCache in interface CacheableCommand
      Returns:
      true if the command was retrieved from cache
      Throws:
      CommandException

    • updateCache

      public void updateCache()
      This method will cause the current command to be placed into the cache. Any existing entry with the same cache id will be replaced.
      Specified by:
      updateCache in interface CacheableCommand

    • getObjectSize

      public long getObjectSize()
      Specified by:
      getObjectSize in interface com.ibm.websphere.cache.Sizeable

    • setObjectSize

      public void setObjectSize(long objectSize)