Param.java

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 * obtain a copy of the License at
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package org.glassfish.api;

import org.jvnet.hk2.config.Attribute;

import java.lang.annotation.Retention;
import java.lang.annotation.Target;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

/**
 * Param is a parameter to a command. This annotation can be placed on a field or
 * setter method to identify the parameters of a command and have those parameters
 * injected by the system before the command is executed.
 *
 * The system will check that all non optional parameters are satisfied before invoking
 * the command.
 *
 * @author Jerome Dochez
 */
@Retention(RUNTIME)
@Target({METHOD,FIELD})
public @interface Param {

    /**
     * Returns the name of the parameter as it has be specified by the client when invoking
     * the command. By default the name is deducted from the name of the annotated element.
     * If the annotated element is a field, it is the filed name.
     * If the annotated element is a method, it is the JavaBeans property name from the setter
     * method name
     *
     * @return the parameter name.
     */
    public String name() default "";

    /**
     * Returns a list of comma separated acceptable values for this parameter. The system
     * will check that one of the value is used before invoking the command.
     *
     * @return the list of comma separated acceptable values
     */
    public String acceptableValues() default "";

    /**
     * Returns true if the parameter is optional to the successful invocation of the command
     * @return true if the parameter is optional
     */
    public boolean optional() default false;

    /**
     * Returns the short name associated with the parameter so that the user can specify
     * -p as well as -password when invoking the command.
     *
     * @return the parameter short name
     */
    public String shortName() default "";

    /**
     * Returns true if this is the primary parameter for the command which mean that the
     * client does not have to pass the parameter name but just the value to the command.
     *
     * @return true if this is the primary command parameter.
     */
    public boolean primary() default false;

    /**
     * Returns the default value associated with the parameter
     *  so that the user can specify
     *
     * @return the parameter default value
     */
    public String defaultValue() default "";
    
    /**
     * Returns a class that calculates the default value associated with the 
     * parameter.
     * 
     * @return a parameter default value calculator
     */
    public Class<? extends ParamDefaultCalculator> defaultCalculator() default ParamDefaultCalculator.class;
    
    /**
     * Returns true if the parameter is a password
     * @return true if the parameter is password
     */
    public boolean password() default false;

    /**
     * Returns the character used to separate items in a list.
     * Applies to parameters of type List, Properties, and String[].
     * The default separator is comma.
     *
     * @return the separator character
     */
    public char separator() default ',';

    /**
     * Returns true if multiple instances of the parameter are allowed.
     *
     * @return true if multiple instances are allowed
     */
    public boolean multiple() default false;

    /**
     * Returns true if this parameter is obsolete.
     * Obsolete parameters produce warnings when used in asadmin,
     * are ignored, and are not included in the command usage.
     *
     * @return true if the parameter is obsolete
     */
    public boolean obsolete() default false;

    /**
     * Returns an alias for the option.
     * This supports renaming options and supporting both the old name
     * and the new name.
     *
     * @return the parameter alias
     */
    public String alias() default "";
}