org.unix4j.unix.uniq.UniqOptions Maven / Gradle / Ivy
package org.unix4j.unix.uniq;
import java.util.Collections;
import java.util.Iterator;
import org.unix4j.convert.OptionSetConverters.OptionSetConverter;
import org.unix4j.convert.ValueConverter;
import org.unix4j.option.DefaultOptionSet;
import org.unix4j.option.Option;
import org.unix4j.option.OptionSet;
import org.unix4j.unix.Uniq;
import org.unix4j.unix.uniq.UniqOption;
/**
* Interface implemented by all option sets for the {@link Uniq uniq} command.
* It is recommended to use {@link Uniq#Options} to specify a valid
* combination of options.
*
* The options for the uniq command are:
*
*
* {@code -c} {@code --count} Precedes each output line with a count of the number of times the
line occurred in the input. {@code -d} {@code --duplicatedOnly} Suppresses the writing of lines that are not repeated in the input. {@code -u} {@code --uniqueOnly} Suppresses the writing of lines that are repeated in the input. {@code -g} {@code --global} Suppresses repeated lines globally, that is, if lines are
non-adjacent. This option guarantees unique output lines even if the
input lines are not sorted.
*
* This interface serves as an alias for the extended interface to simplify the
* command signature methods by avoiding generic parameters.
*/
public interface UniqOptions extends OptionSet {
/**
* Constant for an empty option set.
*/
UniqOptions EMPTY = new UniqOptions() {
@Override
public Class optionType() {
return UniqOption.class;
}
@Override
public boolean isSet(UniqOption option) {
return false;
}
/**
* Returns 0 as this is a set with no active options.
*
* @return zero
*/
@Override
public int size() {
return 0;
}
/**
* Returns an immutable empty set.
*
* @return an immutable empty set.
*/
@Override
public java.util.Set asSet() {
return Collections.emptySet();
}
/**
* Returns an iterator returning no elements.
*
* @return an immutable iterator with no elements.
*/
@Override
public Iterator iterator() {
return asSet().iterator();
}
/**
* Returns true if the {@link Option#acronym() acronym} should be used
* for the specified {@code option} in string representations.
*
* This method returns always true;
*
* @param option
* the option of interest
* @return always true
*/
@Override
public boolean useAcronymFor(UniqOption option) {
return true;
}
};
/**
* Default implementation for a modifiable option set.
*/
class Default extends DefaultOptionSet implements UniqOptions {
/**
* Default constructor for an empty option set with no active options.
*/
public Default() {
super(UniqOption.class);
}
/**
* Constructor for an option set with a single active option.
* @param option the option to be set
*/
public Default(UniqOption option) {
super(option);
}
/**
* Constructor for an option set with the given active options.
* @param options the options to be set
*/
public Default(UniqOption... options) {
this();
setAll(options);
}
/**
* Constructor for an option set initialized with the options given by
* another option set.
*
* @param optionSet set with the options to be active
*/
public Default(OptionSet optionSet) {
this();
setAll(optionSet);
}
}
/**
* Value converter for {@link UniqOptions} based on an {@link OptionSetConverter}.
*/
ValueConverter CONVERTER = new ValueConverter() {
private final OptionSetConverter converter = new OptionSetConverter(UniqOption.class);
@Override
public UniqOptions convert(Object value) {
final OptionSet set = converter.convert(value);
return set == null ? null : new Default(set);
}
};
}