/**
* Licensed to jclouds, Inc. (jclouds) under one or more
* contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. jclouds 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
*
* 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.jclouds.collect;
import static com.google.common.base.Preconditions.checkNotNull;
import java.io.IOException;
import java.util.AbstractMap;
import java.util.AbstractSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import com.google.common.base.Function;
import com.google.common.base.Throwables;
import com.google.common.io.InputSupplier;
/**
*
*
* @author Adrian Cole
*
*/
public class InputSupplierMap<K, V> extends AbstractMap<K, V> {
private final Map<K, InputSupplier<V>> toMap;
private final Function<V, InputSupplier<V>> putFunction;
public InputSupplierMap(Map<K, InputSupplier<V>> toMap, Function<V, InputSupplier<V>> putFunction) {
this.toMap = checkNotNull(toMap);
this.putFunction = checkNotNull(putFunction);
}
@Override
public int size() {
return toMap.size();
}
@Override
public V put(K key, V value) {
V old = get(key);
toMap.put(key, value != null ? putFunction.apply(value) : null);
return old;
}
@Override
public boolean containsKey(Object key) {
return toMap.containsKey(key);
}
@Override
public V get(Object key) {
InputSupplier<V> value = toMap.get(key);
try {
return value != null ? value.getInput() : null;
} catch (IOException e) {
throw Throwables.propagate(e);
}
}
@Override
public V remove(Object key) {
try {
return toMap.containsKey(key) ? toMap.remove(key).getInput() : null;
} catch (IOException e) {
throw Throwables.propagate(e);
}
}
@Override
public void clear() {
toMap.clear();
}
@Override
public Set<Entry<K, V>> entrySet() {
return new EntrySet();
}
private class EntrySet extends AbstractSet<Entry<K, V>> {
@Override
public int size() {
return InputSupplierMap.this.size();
}
@Override
public Iterator<Entry<K, V>> iterator() {
final Iterator<java.util.Map.Entry<K, InputSupplier<V>>> mapIterator = toMap.entrySet().iterator();
return new Iterator<Entry<K, V>>() {
public boolean hasNext() {
return mapIterator.hasNext();
}
public Entry<K, V> next() {
final java.util.Map.Entry<K, InputSupplier<V>> entry = mapIterator.next();
return new AbstractMapEntry<K, V>() {
@Override
public K getKey() {
return entry.getKey();
}
@Override
public V getValue() {
try {
return entry.getValue().getInput();
} catch (IOException e) {
throw Throwables.propagate(e);
}
}
};
}
public void remove() {
mapIterator.remove();
}
};
}
@Override
public void clear() {
toMap.clear();
}
@Override
public boolean contains(Object o) {
if (!(o instanceof Entry)) {
return false;
}
Entry<?, ?> entry = (Entry<?, ?>) o;
Object entryKey = entry.getKey();
Object entryValue = entry.getValue();
V mapValue = InputSupplierMap.this.get(entryKey);
if (mapValue != null) {
return mapValue.equals(entryValue);
}
return entryValue == null && containsKey(entryKey);
}
@Override
public boolean remove(Object o) {
if (contains(o)) {
Entry<?, ?> entry = (Entry<?, ?>) o;
Object key = entry.getKey();
toMap.remove(key);
return true;
}
return false;
}
}
}