Adding Parameters to an asadmin Command

The parameters of an asadmin command are the options and operands of the command.

• Options control how the asadmin utility performs a command.

• Operands are the objects on which a command acts. For example, the operand of the start-domain(1) command is the domain that is to be started.

The following topics are addressed here:

• Representing a Parameter of an asadmin Command

• Identifying a Parameter of an asadmin Command

• Specifying Whether a Parameter Is an Option or an Operand

• Specifying the Name of an Option

• Specifying the Acceptable Values of a Parameter

• Specifying the Default Value of a Parameter

• Specifying Whether a Parameter Is Required or Optional

• Example of Adding Parameters to an asadmin Command

Representing a Parameter of an asadmin Command

Represent each parameter of a command in your implementation as a field or as the property of a JavaBeans specification setter method. Use the property of a setter method for the following reasons:

• To provide data encapsulation for the parameter

• To add code for validating the parameter before the property is set

Identifying a Parameter of an asadmin Command

Identifying a parameter of an asadmin command enables Enterprise Server to perform the following operations at runtime on the parameter:

• Validation. The Enterprise Server determines whether all required parameters are specified and returns an error if any required parameter is omitted.

• Injection. Before the command runs, the Enterprise Server injects each parameter into the required field or method before the command is run.

• Usage message generation. The Enterprise Server uses reflection to obtain the list of parameters for a command and to generate the usage message from this list.

• Localized string display. If the command supports internationalization and if localized strings are available, the Enterprise Server can automatically obtain the localized strings for a command and display them to the user.

To identify a parameter of a command, annotate the declaration of the item that is associated with the parameter with the org.glassfish.api.Param annotation. This item is either the field or setter method that is associated with the parameter.

To specify the properties of the parameter, use the elements of the @Param annotation as explained in the sections that follow.

Specifying Whether a Parameter Is an Option or an Operand

Whether a parameter is an option or an operand determines how a user must specify the parameter when running the command:

• If the parameter is an option, the user must specify the option with the parameter name.

• If the parameter is an operand, the user may omit the parameter name.

To specify whether a parameter is an option or an operand, set the primary element of the @Param annotation as follows:

• If the parameter is an option, set the primary element to false. This value is the default.

• If the parameter is an operand, set the primary element to true.

Specifying the Name of an Option

The name of an option is the name that a user must type on the command line to specify the option when running the command.

The name of each option that you add in your implementation of an asadmin command can have a long form and a short form. When running the command, the user specifies the long form and the short form as follows:

• The short form of an option name has a single dash (-) followed by a single character.

• The long form of an option name has two dashes (--) followed by an option word.

For example, the short form and the long form of the name of the option for specifying terse output are as follows:

• Short form: -m

• Long form: --monitor

Specifying the Long Form of an Option Name

To specify the long form of an option name, set the name element of the @Param annotation to a string that specifies the name. If you do not set this element, the default name depends on how you represent the option.

• If you represent the option as a field, the default name is the field name.

• If you represent the option as the property of a JavaBeans specification setter method, the default name is the property name from the setter method name. For example, if the setter method setPassword is associated with an option, the property name and the option name are both password.

Specifying the Short Form of an Option Name

To specify the short form of an option name, set the shortName element of the @Param annotation to a single character that specifies the short form of the parameter. The user can specify this character instead of the full parameter name, for example -m instead of --monitor. If you do not set this element, the option has no short form.

Specifying the Acceptable Values of a Parameter

When a user runs the command, the Enterprise Server validates option arguments and operands against the acceptable values that you specify in your implementation.

To specify the acceptable values of a parameter, set the acceptableValues element of the @Param annotation to a string that contains a comma-separated list of acceptable values. If you do not set this element, any string of characters is acceptable.

Specifying the Default Value of a Parameter

The default value of a parameter is the value that is applied if a user omits the parameter when running the command.

To specify the default value of a parameter, set the defaultValue element of the @Param annotation to a string that contains the default value. If you do not set this element, the parameter has no default value.

Specifying Whether a Parameter Is Required or Optional

Whether a parameter is required or optional determines how a command responds if a user omits the parameter when running the command:

• If the parameter is required, the command returns an error.

• If the parameter is optional, the command runs successfully.

To specify whether a parameter is optional or required, set the optional element of the @Param annotation as follows:

• If the parameter is required, set the optional element to false. This value is the default.

• If the parameter is optional, set the optional element to true.

Example of Adding Parameters to an asadmin Command

Adding Parameters to an asadmin Command

This example shows the code for adding parameters to an asadmin command with the properties as shown in the table.

Name Represented As Acceptable Values Default Value Optional or Required Short Name Option or Operand --originator A field that is named originator Any character string None defined Required None Option --description A field that is named mycontainerDescription Any character string None defined Optional None Option --enabled A field that is named enabled true or false false Optional None Option --containername A field that is named containername Any character string None defined Required None Operand

...
import org.glassfish.api.Param;
...
{
…
    @Param
    String originator;
    
    @Param(name="description", optional=true)
    …
    String mycontainerDescription
    
    @Param (acceptableValues="true,false", defaultValue="false", optional=true)
    String enabled
    
    @Param(primary=true)
    String containername;
…
}