Class AbstractOperand<T>

java.lang.Object
org.refcodes.cli.AbstractOperand<T>
Type Parameters:
T - the generic type
All Implemented Interfaces:
Cloneable, Comparable<Operand<?>>, ArgsAccessor, Constituent, Operand<T>, Synopsisable, org.refcodes.mixin.AliasAccessor, org.refcodes.mixin.Clonable, org.refcodes.mixin.DescriptionAccessor, org.refcodes.mixin.Resetable, org.refcodes.mixin.Schemable, org.refcodes.mixin.TypeAccessor<T>, org.refcodes.mixin.ValueAccessor<T>
Direct Known Subclasses:
AbstractOption, NoneOperand, Operation, StringOperand

public abstract class AbstractOperand<T> extends Object implements Operand<T>
The AbstractOperand is an abstract implementation of an Operand providing the boiler plate when implementing the Operand interface.
  • Field Details

    • _value

      protected T _value
    • _description

      protected String _description
  • Constructor Details

    • AbstractOperand

      public AbstractOperand(Class<T> aType, String aAlias, String aDescription)
      Constructs a Operand with the given arguments.
      Parameters:
      aType - The type of the value returned by the getValue() method.
      aAlias - The Operand's name, used for syntax creation.
      aDescription - The description to be used (without any line breaks).
    • AbstractOperand

      public AbstractOperand(org.refcodes.struct.Relation<String,T> aProperty, Class<T> aType)
      Instantiates a new operand.
      Parameters:
      aProperty - The key (= alias) and the value for the operand.
      aType - the type
  • Method Details

    • parseArgs

      public List<Operand<T>> parseArgs(String[] aArgs, String[] aOptions, CliContext aCliContext) throws ArgsSyntaxException
      Parses the provided command line arguments and determines the according values by evaluating this Constituent instance or, in case of being a node in the syntax tree (such as a Condition, traversing the child Constituent instances' Constituent.parseArgs(String[], String[], CliContext) methods. In case of successfully parsing this Constituent and / or the child Constituent instances, the evaluated command line arguments are returned: Depending on the Constituent subclasses representing the evaluated command line arguments, instances of Flag classes, Option classes or Operand classes may be found in the result. In case of parsing failure, an according exception is thrown. ATTENTION: This method does not test for superfluous command line arguments being passed; e.g. command line arguments not being evaluated by any of the Constituent instance being traversed. This method is commonly used by a root Constituent's ArgsParser.evalArgs(String[]) method, which delegates to the Constituent.parseArgs(String[], String[], CliContext) method and after which it determines whether there are superfluous arguments to be taken care of (by throwing an according exception). Business logic therefore should invoke the root node's Constituent.parseArgs(String[], String[], CliContext) method as ignoring superfluous command line arguments will aCause unexpected behavior from the point of view of the invoker.
      Specified by:
      parseArgs in interface Constituent
      Parameters:
      aArgs - The command line arguments to be parsed.
      aOptions - The list of options (short and as well as long) which are reserved and cannot be used as value.
      aCliContext - the cli context
      Returns:
      The list of evaluated command line arguments being instances of the Operand interfaces or its sub-types.
      Throws:
      ArgsSyntaxException - thrown in case of a command line arguments mismatch regarding provided and expected args.
    • toSyntax

      public String toSyntax(CliContext aCliCtx)
      This method is to be called from inside the Constituent hierarchy; use the method Synopsisable.toSynopsis(SyntaxNotation) in case you invoke syntax retrieval from the root Constituent. Returns the human readable (verbose) syntax of this Constituent instance including, in case of being a node in the syntax tree (such as a Condition, the syntax of the child Constituent instances. ATTENTION: As of different parenthesis settings for some notations regarding the root Constituent and the child Constituents, the method Constituent.toSyntax(CliContext) is called from inside the Constituent hierarchy. In case the syntax is to be retrieved from the root Constituent, then the applicable method to be called is Synopsisable.toSynopsis(SyntaxNotation), as for some notations it will for example not create the most outer braces.
      Specified by:
      toSyntax in interface Constituent
      Parameters:
      aCliCtx - The CliContext for which the syntax is being generated.
      Returns:
      The human readable (verbose) command line arguments syntax.
    • getAlias

      public String getAlias()
      Retrieves the name (alias) of the parameter value which can be the name of the operand (Operand) or the option argument (Option), depending on the sub-type inheriting from this interface. The parameter name is merely used for constructing the command line arguments syntax String via Constituent.toSyntax(CliContext) and the command line arguments detail description when creating a command line tool's help output. Attention: The alias can also be used as a key when putting an Operand's key/value-pair into a dictionary such as is done by the ApplicationProperties type provided by the refcodes-properties-ext-runime artifact!
      Specified by:
      getAlias in interface org.refcodes.mixin.AliasAccessor
      Specified by:
      getAlias in interface Operand<T>
      Returns:
      The name of the parameter, e.g the name of the operand or the name of the option argument.
    • getType

      public Class<T> getType()
      Specified by:
      getType in interface org.refcodes.mixin.TypeAccessor<T>
    • getValue

      public T getValue()
      Specified by:
      getValue in interface Operand<T>
      Specified by:
      getValue in interface org.refcodes.mixin.ValueAccessor<T>
    • toParsedArgs

      public String[] toParsedArgs()
      Retrieves the (command line) args which represent this Operand after being "parsed" (provided with command line args).
      Specified by:
      toParsedArgs in interface ArgsAccessor
      Specified by:
      toParsedArgs in interface Operand<T>
      Returns:
      The according args from the command line args.
    • reset

      public void reset()
      Specified by:
      reset in interface org.refcodes.mixin.Resetable
    • toString

      public String toString()
      Overrides:
      toString in class Object
    • compareTo

      public int compareTo(Operand<?> obj)
      Specified by:
      compareTo in interface Comparable<T>
    • clone

      public Object clone() throws CloneNotSupportedException
      Specified by:
      clone in interface org.refcodes.mixin.Clonable
      Overrides:
      clone in class Object
      Throws:
      CloneNotSupportedException
    • toSchema

      public CliSchema toSchema()
      Specified by:
      toSchema in interface Constituent
      Specified by:
      toSchema in interface org.refcodes.mixin.Schemable
    • setValue

      protected void setValue(T aValue)
      Sets the value for the Operand as parsed by the parseArgs(String[], String[], CliContext) method.
      Parameters:
      aValue - The value to be set for this Operand.
    • setParsedArgs

      protected void setParsedArgs(String[] aArgs)
      Sets the command line argument(s) representing the Operand and its value as parsed by the parseArgs(String[], String[], CliContext) method.
      Parameters:
      aArgs - The command line arguments representing this Operand with its value.
    • toType

      protected abstract T toType(String aArg) throws ParseArgsException
      Double dispatch hook to be implemented by subclasses of the AbstractOperand for converting a command line argument to the required Operand's type. In case conversion failed, then an according exception is to be thrown.
      Parameters:
      aArg - The command line argument to be converted to an instance of the given type T.
      Returns:
      An instance of type T from the provided command line argument.
      Throws:
      ParseArgsException - Thrown in case the provided command line arguments do not respect the required syntax or cannot be converted to the required type.
    • getDescription

      public String getDescription()
      Specified by:
      getDescription in interface org.refcodes.mixin.DescriptionAccessor