Package com.ibm.websphere.command

Class TargetableCommandImpl

java.lang.Object
com.ibm.websphere.command.TargetableCommandImpl
All Implemented Interfaces:
Command, TargetableCommand, Serializable
Direct Known Subclasses:
CacheableCommandImpl
public abstract class TargetableCommandImpl extends Object implements TargetableCommand
The TargetableCommandImpl class implements the generic methods in the TargetableCommand interface. Application programmers must implement the application-specific methods. The TargetableCommand interface provides support for the remote execution of commands, and the TargetableCommandImpl class provides a runtime for command execution.

All targetable commands extend the TargetableCommandImpl class.

See Also:

  • Field Details

    • LOCAL

      public static String LOCAL
      A target object that executes a command within the client's JVM. This implementation is provided in the LocalTarget class.

      This is static so that it is easy to obtain.

  • Constructor Details

    • TargetableCommandImpl

      public TargetableCommandImpl()

  • Method Details

    • execute

      public void execute() throws CommandException
      Executes the task encapsulated by the command. This is the default implementation for the execute() method in the Command interface, but it can be overridden by the application programmer.

      This implementation of the execute() method does the following:

      • Throws an UnsetInputPropertiesException if the isReadyToCallExecute method returns false for the command.
      • Gets the target for the command according to the target policy.
      • Invokes the executeCommand() method on the target, which in turn calls the performExecute() method on the command.
      • Copies output values by using the setOutputProperties() method if the hasOutputProperties() method returns true and if the returned command is not the same instance as this command.

      Specified by:
      execute in interface Command
      Throws:
      CommandException - The superclass for all command exceptions. Specificially, UnsetInputPropertiesException is thrown if this command's isReadyToCallExecute() method returns false.

    • getCommandTarget

      public CommandTarget getCommandTarget()
      Returns the target object for the command. This implements the getCommandTarget() method declared in the TargetableCommand interface.
      Specified by:
      getCommandTarget in interface TargetableCommand
      Returns:
      The target object, which locates the server where the command will run.

    • getCommandTargetName

      public String getCommandTargetName()
      Returns the name of the target object for the command. This implements the getCommandTargetName() method declared in the TargetableCommand interface.
      Specified by:
      getCommandTargetName in interface TargetableCommand
      Returns:
      The fully qualified name of the Java class of the target object.

    • getTargetPolicy

      public static TargetPolicy getTargetPolicy()
      Returns the target policy for the command.

    • hasOutputProperties

      public final boolean hasOutputProperties()
      Indicates if the command has any output properties that will have to be returned to the client. This implements the hasOutputProperties() method in the TargetableCommand interface.
      Specified by:
      hasOutputProperties in interface TargetableCommand
      Returns:
      The value true if the command has output properties that must be copied back to the client.

    • isReadyToCallExecute

      public abstract boolean isReadyToCallExecute()
      Indicates if all required input properties have been set. This abstract method is declared in the Command interface and must be implemented by the application programmer.

      A typical implementation simply checks whether the required input properties are set: 

            return (inputProperties != null)

      Specified by:
      isReadyToCallExecute in interface Command
      Returns:
      The value true if all required input properties are set and the command can be run.

    • performExecute

      public abstract void performExecute() throws Exception
      Runs the business logic that makes up the command. This abstract method is declared in the TargetableCommand interface and must be implemented by the application programmer. It is called by the executeCommand() method on the command target.
      Specified by:
      performExecute in interface TargetableCommand
      Throws:
      Exception - Any exception that occurs in this method is thrown as an Exception or CommandException.

    • reset

      public abstract void reset()
      Sets the output properties to the values they had before the the execute method was run. This abstract method is declared in the Command interface and must be implemented by the application programmer.

      A typical implementation just resets the output property variables: 

            outputPropertyP = null;
      outputPropertyQ = 0;

      Specified by:
      reset in interface Command

    • setCommandTarget

      public void setCommandTarget(CommandTarget commandTarget)
      Sets the target object on the command. This implements the setCommandTarget() method declared in the TargetableCommand interface.
      Specified by:
      setCommandTarget in interface TargetableCommand
      Parameters:
      commandTarget - The target object, which locates the server where the command will run.

    • setCommandTargetName

      public void setCommandTargetName(String commandTargetName)
      Sets the name of the target object on the command. This implements the setCommandTargetName() method declared in the TargetableCommand interface.
      Specified by:
      setCommandTargetName in interface TargetableCommand
      Parameters:
      commandTargetName - The fully qualified name of the Java class of the target object.

    • setHasOutputProperties

      public final void setHasOutputProperties(boolean inProp)
      Sets the hasOutputProperties class variable to indicate if the command has output properties that must be returned to the client.
      Parameters:
      inProp - A boolean indicating if there are output properties to be returned to the client.

    • setOutputProperties

      public void setOutputProperties(TargetableCommand fromCommand)
      Sets the return values on the command. This is the default implementation for the setOutputProperties() method in the TargetableCommand interface, but it can be overridden by the application programmer.

      This implementation uses introspection to copy all instance variables, provided that they are non-private and non-package; that is, must be public or protected. This implementation does not copy the final, static or transient fields.

      If this implementation is not acceptable, the programmer can override this method. A typical re-implementation does the following: 

            this.outputPropertyA = fromCommand.outputPropertyA;
      this.outputPropertyB = fromCommand.outputPropertyB;

      Specified by:
      setOutputProperties in interface TargetableCommand
      Parameters:
      fromCommand - The command from which the output properties are copied.

    • setTargetPolicy

      public static void setTargetPolicy(TargetPolicy targetPolicy)
      Sets the target policy for the command.
      Parameters:
      targetPolicy - The target policy for the command.