joptsimple

Class BuiltinHelpFormatter

java.lang.Object

joptsimple.BuiltinHelpFormatter

All Implemented Interfaces:

HelpFormatter

public class BuiltinHelpFormatter
extends java.lang.Object
implements HelpFormatter

A help formatter that allows configuration of overall row width and column separator width.

The formatter produces output in two sections: one for the options, and one for non-option arguments.

The options section has two columns: the left column for the options, and the right column for their descriptions. The formatter will allow as much space as possible for the descriptions, by minimizing the option column's width, no greater than slightly less than half the overall desired width.

The non-option arguments section is one column, occupying as much width as it can.

Subclasses are free to override bits of this implementation as they see fit. Inspect the code carefully to understand the flow of control that this implementation guarantees.

Field Summary

Fields

Modifier and Type	Field and Description
private Rows	nonOptionRows
private Rows	optionRows

Constructor Summary

Constructors

Constructor and Description
BuiltinHelpFormatter() Makes a formatter with a pre-configured overall row width and column separator width.
BuiltinHelpFormatter(int desiredOverallWidth, int desiredColumnSeparatorWidth) Makes a formatter with a given overall row width and column separator width.

Method Summary

Modifier and Type	Method and Description
protected void	addHeaders(java.util.Collection<? extends OptionDescriptor> options) Adds help row headers for option help columns.
protected void	addNonOptionRow(java.lang.String single) Adds a single row of non-option argument help.
protected void	addNonOptionsDescription(java.util.Collection<? extends OptionDescriptor> options) Adds non-option arguments descriptions to the help output.
protected void	addOptionRow(java.lang.String single) Adds a row of option help output in the left column, with empty space in the right column.
protected void	addOptionRow(java.lang.String left, java.lang.String right) Adds a row of option help output in the left and right columns.
protected void	addOptions(java.util.Collection<? extends OptionDescriptor> options) Adds help rows for the given options.
protected void	addRows(java.util.Collection<? extends OptionDescriptor> options) Adds rows of help output for the given options.
protected void	appendOptionHelp(java.lang.StringBuilder buffer, java.lang.String typeIndicator, java.lang.String description, boolean required) Appends info about an option's argument to the given buffer.
protected void	appendTypeIndicator(java.lang.StringBuilder buffer, java.lang.String typeIndicator, java.lang.String description, char start, char end) Appends a type indicator for an option's argument to the given buffer.
protected java.lang.String	createDefaultValuesDisplay(java.util.List<?> defaultValues) Gives a display string for the default values of an option's argument.
protected java.lang.String	createDescriptionDisplay(OptionDescriptor descriptor) Gives a string representing a description of the option with the given descriptor.
protected java.lang.String	createNonOptionArgumentsDisplay(OptionDescriptor nonOptionDescriptor) Creates a non-options argument help string.
protected java.lang.String	createOptionDisplay(OptionDescriptor descriptor) Creates a string for how the given option descriptor is to be represented in help.
protected java.lang.String	extractTypeIndicator(OptionDescriptor descriptor) Gives an indicator of the type of arguments of the option described by the given descriptor, for use in help.
protected OptionDescriptor	findAndRemoveNonOptionsSpec(java.util.Collection<? extends OptionDescriptor> options) Finds the non-option arguments descriptor in the given collection, removes it, and returns it.
protected void	fitRowsToWidth() Resizes the columns of all the rows to be no wider than the widest element in that column.
java.lang.String	format(java.util.Map<java.lang.String,? extends OptionDescriptor> options) Produces help text, given a set of option descriptors.
protected java.lang.String	formattedHelpOutput() Produces help output for an entire set of options and non-option arguments.
protected boolean	hasRequiredOption(java.util.Collection<? extends OptionDescriptor> options) Tells whether the given option descriptors contain a "required" option.
protected void	maybeAppendNonOptionsDescription(java.lang.StringBuilder buffer, OptionDescriptor nonOptions) Appends help for the given non-option arguments descriptor to the given buffer.
protected void	maybeAppendOptionInfo(java.lang.StringBuilder buffer, OptionDescriptor descriptor) Appends additional info about the given option to the given buffer.
protected java.lang.String	message(java.lang.String keySuffix, java.lang.Object... args) Looks up and gives a resource bundle message.
protected java.lang.String	nonOptionOutput() Produces non-option argument help.
protected java.lang.String	optionLeader(java.lang.String option) Gives a string that represents the given option's "option leader" in help.
protected java.lang.String	optionOutput() Produces help for options and their descriptions.
protected boolean	shouldShowNonOptionArgumentDisplay(OptionDescriptor nonOptionDescriptor) Decides whether or not to show a non-option arguments help.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

nonOptionRows

private final Rows nonOptionRows

optionRows

private final Rows optionRows

Constructor Detail

BuiltinHelpFormatter

BuiltinHelpFormatter()

Makes a formatter with a pre-configured overall row width and column separator width.

BuiltinHelpFormatter

public BuiltinHelpFormatter(int desiredOverallWidth,
                            int desiredColumnSeparatorWidth)

Makes a formatter with a given overall row width and column separator width.

Parameters:

desiredOverallWidth - how many characters wide to make the overall help display

desiredColumnSeparatorWidth - how many characters wide to make the separation between option column and description column

Method Detail

format

public java.lang.String format(java.util.Map<java.lang.String,? extends OptionDescriptor> options)

Produces help text, given a set of option descriptors.

This implementation:

• Sorts the given descriptors by their first elements of OptionDescriptor.options()
• Passes the resulting sorted set to addRows(java.util.Collection)
• Returns the result of formattedHelpOutput()

Specified by:

format in interface HelpFormatter

Parameters:

options - descriptors for the configured options of a parser

Returns:

text to be used as help

See Also:

OptionParser.printHelpOn(java.io.Writer), OptionParser.formatHelpWith(HelpFormatter)

addOptionRow

protected void addOptionRow(java.lang.String single)

Adds a row of option help output in the left column, with empty space in the right column.

Parameters:

single - text to put in the left column

addOptionRow

protected void addOptionRow(java.lang.String left,
                            java.lang.String right)

Adds a row of option help output in the left and right columns.

Parameters:

left - text to put in the left column

right - text to put in the right column

addNonOptionRow

protected void addNonOptionRow(java.lang.String single)

Adds a single row of non-option argument help.

Parameters:

single - single row of non-option argument help text

fitRowsToWidth

protected void fitRowsToWidth()

Resizes the columns of all the rows to be no wider than the widest element in that column.

nonOptionOutput

protected java.lang.String nonOptionOutput()

Produces non-option argument help.

Returns:

non-option argument help

optionOutput

protected java.lang.String optionOutput()

Produces help for options and their descriptions.

Returns:

option help

formattedHelpOutput

protected java.lang.String formattedHelpOutput()

Produces help output for an entire set of options and non-option arguments.

This implementation concatenates:

• the result of nonOptionOutput()
• if there is non-option output, a line separator
• the result of optionOutput()

Returns:

help output for entire set of options and non-option arguments

addRows

protected void addRows(java.util.Collection<? extends OptionDescriptor> options)

Adds rows of help output for the given options.

This implementation:

• Calls addNonOptionsDescription(java.util.Collection) with the options as the argument
• If there are no options, calls addOptionRow(String) with an argument that indicates that no options are specified.
• Otherwise, calls addHeaders(java.util.Collection) with the options as the argument, followed by addOptions(java.util.Collection) with the options as the argument.
• Calls fitRowsToWidth().

Parameters:

options - descriptors for the configured options of a parser

addNonOptionsDescription

protected void addNonOptionsDescription(java.util.Collection<? extends OptionDescriptor> options)

Adds non-option arguments descriptions to the help output.

This implementation:

• Finds and removes the non-option arguments descriptor
• Decides whether there is anything to show for non-option arguments
• If there is, adds a header row and adds a non-option arguments description

Parameters:

options - descriptors for the configured options of a parser

shouldShowNonOptionArgumentDisplay

protected boolean shouldShowNonOptionArgumentDisplay(OptionDescriptor nonOptionDescriptor)

Decides whether or not to show a non-option arguments help.

This implementation responds with true if the non-option descriptor has a non-null, non-empty value for any of OptionDescriptor.description(), OptionDescriptor.argumentTypeIndicator(), or OptionDescriptor.argumentDescription().

Parameters:

nonOptionDescriptor - non-option argument descriptor

Returns:

true if non-options argument help should be shown

createNonOptionArgumentsDisplay

protected java.lang.String createNonOptionArgumentsDisplay(OptionDescriptor nonOptionDescriptor)

Creates a non-options argument help string.

This implementation creates an empty string buffer and calls maybeAppendOptionInfo(StringBuilder, OptionDescriptor) and maybeAppendNonOptionsDescription(StringBuilder, OptionDescriptor), passing them the buffer and the non-option arguments descriptor.

Parameters:

nonOptionDescriptor - non-option argument descriptor

Returns:

help string for non-options

maybeAppendNonOptionsDescription

protected void maybeAppendNonOptionsDescription(java.lang.StringBuilder buffer,
                                                OptionDescriptor nonOptions)

Appends help for the given non-option arguments descriptor to the given buffer.

This implementation appends " -- " if the buffer has text in it and the non-option arguments descriptor has a OptionDescriptor.description(); followed by the OptionDescriptor.description().

Parameters:

buffer - string buffer

nonOptions - non-option arguments descriptor

findAndRemoveNonOptionsSpec

protected OptionDescriptor findAndRemoveNonOptionsSpec(java.util.Collection<? extends OptionDescriptor> options)

Finds the non-option arguments descriptor in the given collection, removes it, and returns it.

Parameters:

options - descriptors for the configured options of a parser

Returns:

the non-option arguments descriptor

addHeaders

protected void addHeaders(java.util.Collection<? extends OptionDescriptor> options)

Adds help row headers for option help columns.

This implementation uses the headers "Option" and "Description". If the options contain a "required" option, the "Option" header looks like "Option (* = required). Both headers are "underlined" using "-".

Parameters:

options - descriptors for the configured options of a parser

hasRequiredOption

protected final boolean hasRequiredOption(java.util.Collection<? extends OptionDescriptor> options)

Tells whether the given option descriptors contain a "required" option.

Parameters:

options - descriptors for the configured options of a parser

Returns:

true if at least one of the options is "required"

addOptions

protected void addOptions(java.util.Collection<? extends OptionDescriptor> options)

Adds help rows for the given options.

This implementation loops over the given options, and for each, calls addOptionRow(String, String) using the results of createOptionDisplay(OptionDescriptor) and createDescriptionDisplay(OptionDescriptor), respectively, as arguments.

Parameters:

options - descriptors for the configured options of a parser

createOptionDisplay

protected java.lang.String createOptionDisplay(OptionDescriptor descriptor)

Creates a string for how the given option descriptor is to be represented in help.

This implementation gives a string consisting of the concatenation of:

• "* " for "required" options, otherwise ""
• For each of the OptionDescriptor.options() of the descriptor, separated by ", ":
  • optionLeader(String) of the option
  • the option
• the result of maybeAppendOptionInfo(StringBuilder, OptionDescriptor)

Parameters:

descriptor - a descriptor for a configured option of a parser

Returns:

help string

optionLeader

protected java.lang.String optionLeader(java.lang.String option)

Gives a string that represents the given option's "option leader" in help.

This implementation answers with "--" for options of length greater than one; otherwise answers with "-".

Parameters:

option - a string option

Returns:

an "option leader" string

maybeAppendOptionInfo

protected void maybeAppendOptionInfo(java.lang.StringBuilder buffer,
                                     OptionDescriptor descriptor)

Appends additional info about the given option to the given buffer.

This implementation:

• calls extractTypeIndicator(OptionDescriptor) for the descriptor
• calls OptionDescriptor.argumentDescription() for the descriptor
• if either of the above is present, calls appendOptionHelp(StringBuilder, String, String, boolean)

Parameters:

buffer - string buffer

descriptor - a descriptor for a configured option of a parser

extractTypeIndicator

protected java.lang.String extractTypeIndicator(OptionDescriptor descriptor)

Gives an indicator of the type of arguments of the option described by the given descriptor, for use in help.

This implementation asks for the OptionDescriptor.argumentTypeIndicator() of the given descriptor, and if it is present and not "java.lang.String", parses it as a fully qualified class name and returns the base name of that class; otherwise returns "String".

Parameters:

descriptor - a descriptor for a configured option of a parser

Returns:

type indicator text

appendOptionHelp

protected void appendOptionHelp(java.lang.StringBuilder buffer,
                                java.lang.String typeIndicator,
                                java.lang.String description,
                                boolean required)

Appends info about an option's argument to the given buffer.

This implementation calls appendTypeIndicator(StringBuilder, String, String, char, char) with the surrounding characters '<' and '>' for options with required arguments, and with the surrounding characters '[' and ']' for options with optional arguments.

Parameters:

buffer - string buffer

typeIndicator - type indicator

description - type description

required - indicator of "required"-ness of the argument of the option

appendTypeIndicator

protected void appendTypeIndicator(java.lang.StringBuilder buffer,
                                   java.lang.String typeIndicator,
                                   java.lang.String description,
                                   char start,
                                   char end)

Appends a type indicator for an option's argument to the given buffer.

This implementation appends, in order:

• ' '
• start
• the type indicator, if not null
• if the description is present, then ": " plus the description if the type indicator is present; otherwise the description only
• end

Parameters:

buffer - string buffer

typeIndicator - type indicator

description - type description

start - starting character

end - ending character

createDescriptionDisplay

protected java.lang.String createDescriptionDisplay(OptionDescriptor descriptor)

Gives a string representing a description of the option with the given descriptor.

This implementation:

• Asks for the descriptor's OptionDescriptor.defaultValues()
• If they're not present, answers the descriptor's OptionDescriptor.description().
• If they are present, concatenates and returns:
  • the descriptor's OptionDescriptor.description()
  • ' '
  • "default: " plus the result of createDefaultValuesDisplay(java.util.List), surrounded by parentheses

Parameters:

descriptor - a descriptor for a configured option of a parser

Returns:

display text for the option's description

createDefaultValuesDisplay

protected java.lang.String createDefaultValuesDisplay(java.util.List<?> defaultValues)

Gives a display string for the default values of an option's argument.

This implementation gives the Object.toString() of the first value if there is only one value, otherwise gives the Object.toString() of the whole list.

Parameters:

defaultValues - some default values for a given option's argument

Returns:

a display string for those default values

message

protected java.lang.String message(java.lang.String keySuffix,
                                   java.lang.Object... args)

Looks up and gives a resource bundle message.

This implementation looks in the bundle "joptsimple.HelpFormatterMessages" in the default locale, using a key that is the concatenation of this class's fully qualified name, '.', and the given key suffix, formats the corresponding value using the given arguments, and returns the result.

Parameters:

keySuffix - suffix to use when looking up the bundle message

args - arguments to fill in the message template with

Returns:

a formatted localized message