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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * Copyright 2014 The Netty Project
 *
 * The Netty Project licenses this file to you 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:
 *
 * https://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 io.netty.util.collection;

import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Set;

/**
 * Utilities for short-based primitive collections.
 */
public final class ShortCollections {

    private static final ShortObjectMap EMPTY_MAP = new EmptyMap();

    private ShortCollections() {
    }

    /**
     * Returns an unmodifiable empty {@link ShortObjectMap}.
     */
    @SuppressWarnings("unchecked")
    public static  ShortObjectMap emptyMap() {
        return (ShortObjectMap) EMPTY_MAP;
    }

    /**
     * Creates an unmodifiable wrapper around the given map.
     */
    public static  ShortObjectMap unmodifiableMap(final ShortObjectMap map) {
        return new UnmodifiableMap(map);
    }

    /**
     * An empty map. All operations that attempt to modify the map are unsupported.
     */
    private static final class EmptyMap implements ShortObjectMap {
        @Override
        public Object get(short key) {
            return null;
        }

        @Override
        public Object put(short key, Object value) {
            throw new UnsupportedOperationException("put");
        }

        @Override
        public Object remove(short key) {
            return null;
        }

        @Override
        public int size() {
            return 0;
        }

        @Override
        public boolean isEmpty() {
            return true;
        }

        @Override
        public boolean containsKey(Object key) {
            return false;
        }

        @Override
        public void clear() {
            // Do nothing.
        }

        @Override
        public Set keySet() {
            return Collections.emptySet();
        }

        @Override
        public boolean containsKey(short key) {
            return false;
        }

        @Override
        public boolean containsValue(Object value) {
            return false;
        }

        @Override
        public Iterable> entries() {
            return Collections.emptySet();
        }

        @Override
        public Object get(Object key) {
            return null;
        }

        @Override
        public Object put(Short key, Object value) {
            throw new UnsupportedOperationException();
        }

        @Override
        public Object remove(Object key) {
            return null;
        }

        @Override
        public void putAll(Map m) {
            throw new UnsupportedOperationException();
        }

        @Override
        public Collection values() {
            return Collections.emptyList();
        }

        @Override
        public Set> entrySet() {
            return Collections.emptySet();
        }
    }

    /**
     * An unmodifiable wrapper around a {@link ShortObjectMap}.
     *
     * @param  the value type stored in the map.
     */
    private static final class UnmodifiableMap implements ShortObjectMap {
        private final ShortObjectMap map;
        private Set keySet;
        private Set> entrySet;
        private Collection values;
        private Iterable> entries;

        UnmodifiableMap(ShortObjectMap map) {
            this.map = map;
        }

        @Override
        public V get(short key) {
            return map.get(key);
        }

        @Override
        public V put(short key, V value) {
            throw new UnsupportedOperationException("put");
        }

        @Override
        public V remove(short key) {
            throw new UnsupportedOperationException("remove");
        }

        @Override
        public int size() {
            return map.size();
        }

        @Override
        public boolean isEmpty() {
            return map.isEmpty();
        }

        @Override
        public void clear() {
            throw new UnsupportedOperationException("clear");
        }

        @Override
        public boolean containsKey(short key) {
            return map.containsKey(key);
        }

        @Override
        public boolean containsValue(Object value) {
            return map.containsValue(value);
        }

        @Override
        public boolean containsKey(Object key) {
            return map.containsKey(key);
        }

        @Override
        public V get(Object key) {
            return map.get(key);
        }

        @Override
        public V put(Short key, V value) {
            throw new UnsupportedOperationException("put");
        }

        @Override
        public V remove(Object key) {
            throw new UnsupportedOperationException("remove");
        }

        @Override
        public void putAll(Map m) {
            throw new UnsupportedOperationException("putAll");
        }

        @Override
        public Iterable> entries() {
            if (entries == null) {
                entries = new Iterable>() {
                    @Override
                    public Iterator> iterator() {
                        return new IteratorImpl(map.entries().iterator());
                    }
                };
            }

            return entries;
        }

        @Override
        public Set keySet() {
            if (keySet == null) {
                keySet = Collections.unmodifiableSet(map.keySet());
            }
            return keySet;
        }

        @Override
        public Set> entrySet() {
            if (entrySet == null) {
                entrySet = Collections.unmodifiableSet(map.entrySet());
            }
            return entrySet;
        }

        @Override
        public Collection values() {
            if (values == null) {
                values = Collections.unmodifiableCollection(map.values());
            }
            return values;
        }

        /**
         * Unmodifiable wrapper for an iterator.
         */
        private class IteratorImpl implements Iterator> {
            final Iterator> iter;

            IteratorImpl(Iterator> iter) {
                this.iter = iter;
            }

            @Override
            public boolean hasNext() {
                return iter.hasNext();
            }

            @Override
            public PrimitiveEntry next() {
                if (!hasNext()) {
                    throw new NoSuchElementException();
                }
                return new EntryImpl(iter.next());
            }

            @Override
            public void remove() {
                throw new UnsupportedOperationException("remove");
            }
        }

        /**
         * Unmodifiable wrapper for an entry.
         */
        private class EntryImpl implements PrimitiveEntry {
            private final PrimitiveEntry entry;

            EntryImpl(PrimitiveEntry entry) {
                this.entry = entry;
            }

            @Override
            public short key() {
                return entry.key();
            }

            @Override
            public V value() {
                return entry.value();
            }

            @Override
            public void setValue(V value) {
                throw new UnsupportedOperationException("setValue");
            }
        }
    }
}