/*
- * Sone - Options.java - Copyright © 2010 David Roden
+ * Sone - Options.java - Copyright © 2010–2013 David Roden
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
package net.pterodactylus.sone.core;
-import java.util.ArrayList;
-import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
-import java.util.List;
import java.util.Map;
+import com.google.common.base.Predicate;
+
/**
* Stores various options that influence Sone’s behaviour.
*
public static interface Option<T> {
/**
- * Returns the default value of the option.
- *
- * @return The default value of the option
- */
- public T getDefault();
-
- /**
* Returns the current value of the option. If the current value is not
* set (usually {@code null}), the default value is returned.
*
public T getReal();
/**
- * Sets the current value of the option.
+ * Validates the given value. Note that {@code null} is always a valid
+ * value!
*
* @param value
- * The new value of the option
+ * The value to validate
+ * @return {@code true} if this option does not have a validator, or the
+ * validator validates this object, {@code false} otherwise
*/
- public void set(T value);
-
- }
-
- /**
- * Interface for objects that want to be notified when an option changes its
- * value.
- *
- * @param <T>
- * The type of the option
- * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
- */
- public static interface OptionWatcher<T> {
+ public boolean validate(T value);
/**
- * Notifies an object that an option has been changed.
+ * Sets the current value of the option.
*
- * @param option
- * The option that has changed
- * @param oldValue
- * The old value of the option
- * @param newValue
+ * @param value
* The new value of the option
+ * @throws IllegalArgumentException
+ * if the value is not valid for this option
*/
- public void optionChanged(Option<T> option, T oldValue, T newValue);
+ public void set(T value) throws IllegalArgumentException;
}
/**
- * Basic implementation of an {@link Option} that notifies an
- * {@link OptionWatcher} if the value changes.
+ * Basic implementation of an {@link Option}.
*
* @param <T>
* The type of the option
/** The current value. */
private volatile T value;
- /** The option watcher. */
- private final List<OptionWatcher<T>> optionWatchers = new ArrayList<OptionWatcher<T>>();
+ /** The validator. */
+ private Predicate<T> validator;
/**
* Creates a new default option.
*
* @param defaultValue
* The default value of the option
- * @param optionWatchers
- * The option watchers
*/
- public DefaultOption(T defaultValue, OptionWatcher<T>... optionWatchers) {
- this.defaultValue = defaultValue;
- this.optionWatchers.addAll(Arrays.asList(optionWatchers));
+ public DefaultOption(T defaultValue) {
+ this(defaultValue, null);
}
/**
- * {@inheritDoc}
+ * Creates a new default option.
+ *
+ * @param defaultValue
+ * The default value of the option
+ * @param validator
+ * The validator for value validation (may be {@code null})
*/
- @Override
- public T getDefault() {
- return defaultValue;
+ public DefaultOption(T defaultValue, Predicate<T> validator) {
+ this.defaultValue = defaultValue;
+ this.validator = validator;
}
/**
* {@inheritDoc}
*/
@Override
+ public boolean validate(T value) {
+ return (validator == null) || (value == null) || validator.apply(value);
+ }
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
public void set(T value) {
+ if ((value != null) && (validator != null) && (!validator.apply(value))) {
+ throw new IllegalArgumentException("New Value (" + value + ") could not be validated.");
+ }
T oldValue = this.value;
this.value = value;
- if (!get().equals(oldValue)) {
- for (OptionWatcher<T> optionWatcher : optionWatchers) {
- optionWatcher.optionChanged(this, oldValue, get());
- }
- }
}
}
/** Holds all {@link String} {@link Option}s. */
private final Map<String, Option<String>> stringOptions = Collections.synchronizedMap(new HashMap<String, Option<String>>());
+ /** Holds all {@link Enum} {@link Option}s. */
+ private final Map<String, Option<? extends Enum<?>>> enumOptions = Collections.synchronizedMap(new HashMap<String, Option<? extends Enum<?>>>());
+
/**
* Adds a boolean option.
*
return stringOptions.get(name);
}
+ /**
+ * Adds an {@link Enum} {@link Option}.
+ *
+ * @param <T>
+ * The enum type
+ * @param name
+ * The name of the option
+ * @param enumOption
+ * The option
+ * @return The given option
+ */
+ public <T extends Enum<T>> Option<T> addEnumOption(String name, Option<T> enumOption) {
+ enumOptions.put(name, enumOption);
+ return enumOption;
+ }
+
+ /**
+ * Returns a {@link Enum} {@link Option}. As the type can probably not be
+ * interred correctly you could help the compiler by calling this method
+ * like this:
+ * <p>
+ *
+ * <pre>
+ * options.<SomeEnum> getEnumOption("SomeEnumOption").get();
+ * </pre>
+ *
+ * @param <T>
+ * The enum type
+ * @param name
+ * The name of the option
+ * @return The enum option, or {@code null} if there is no enum option with
+ * the given name
+ */
+ @SuppressWarnings("unchecked")
+ public <T extends Enum<T>> Option<T> getEnumOption(String name) {
+ return (Option<T>) enumOptions.get(name);
+ }
+
}
projects / Sone.git / blobdiff