/**
* Copyright 2009 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package org.waveprotocol.wave.model.util;
/**
* A read-write interface to a set of strings.
*
* We define this in favor of using a standard Java collections interface
* so that we can write an optimized implementation for GWT.
*
* Null is not permitted as a value. All methods, even {@link #contains(String)}
* will throw an exception for null values.
*
* @author ohler@google.com (Christian Ohler)
*/
public interface StringSet extends ReadableStringSet {
/**
* A function that accepts a String and returns a boolean.
*/
public interface StringPredicate {
boolean apply(String x);
}
/**
* @param s must not be null
* Adds s to the set. If s is already in the set, does nothing.
*/
void add(String s);
/**
* Removes s from the set. If s is not in the set, does nothing.
*/
void remove(String s);
/**
* Removes all strings from the set.
*/
void clear();
/**
* Equivalent to calling add(s) for every s in stringsToAdd.
*/
void addAll(ReadableStringSet stringsToAdd);
/**
* Equivalent to calling remove(s) for every s in stringsToRemove.
*/
void removeAll(ReadableStringSet stringsToRemove);
/**
* Call the predicate for each entry in the set, in undefined order.
* If the predicate returns false, the entry is removed from the
* set; if it returns true, it remains.
*/
void filter(StringPredicate filter);
}