| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF 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.apache.sling.api.wrappers; |
| |
| import java.util.Collection; |
| import java.util.HashMap; |
| import java.util.Map; |
| import java.util.Set; |
| |
| import org.apache.sling.api.resource.ValueMap; |
| import org.apache.sling.api.wrappers.impl.ObjectConverter; |
| import org.jetbrains.annotations.NotNull; |
| import org.jetbrains.annotations.Nullable; |
| |
| /** |
| * An implementation of the {@link ValueMap} based on two {@link ValueMap}s: |
| * - One containing the properties |
| * - Another one containing the defaults to use in case the properties map |
| * does not contain the values. |
| * In case you would like to avoid duplicating properties on multiple resources, |
| * you can use a <code>CompositeValueMap</code> to get a concatenated map of |
| * properties. |
| * @since 2.3 (Sling API Bundle 2.5.0) |
| */ |
| public class CompositeValueMap implements ValueMap { |
| |
| /** |
| * Current properties |
| */ |
| private final ValueMap properties; |
| |
| /** |
| * Default properties |
| */ |
| private final ValueMap defaults; |
| |
| /** |
| * Merge mode |
| */ |
| private final boolean merge; |
| |
| /** |
| * Constructor |
| * @param properties The {@link ValueMap} to read from |
| * @param defaults The default {@link ValueMap} to use as fallback |
| */ |
| public CompositeValueMap(final ValueMap properties, final ValueMap defaults) { |
| this(properties, defaults, true); |
| } |
| |
| /** |
| * Constructor |
| * @param properties The {@link ValueMap} to read from |
| * @param defaults The default {@link ValueMap} to use as fallback |
| * @param merge Merge flag |
| * - If <code>true</code>, getting a key would return the |
| * current property map's value (if available), even if the |
| * corresponding default does not exist. |
| * - If <code>false</code>, getting a key would return |
| * <code>null</code> if the corresponding default does not |
| * exist |
| */ |
| public CompositeValueMap(final ValueMap properties, final ValueMap defaults, boolean merge) { |
| if (properties == null) { |
| throw new IllegalArgumentException("Properties need to be provided"); |
| } |
| this.properties = properties; |
| this.defaults = defaults != null ? defaults : ValueMap.EMPTY; |
| this.merge = merge; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @SuppressWarnings("unchecked") |
| @Nullable |
| public <T> T get(@NotNull String name, @NotNull Class<T> type) { |
| Object value = get(name); |
| if (value == null) { |
| return null; |
| } |
| if (type.isAssignableFrom(value.getClass())) { |
| return (T)value; |
| } |
| return ObjectConverter.convert(value,type); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @SuppressWarnings("unchecked") |
| @NotNull |
| public <T> T get(@NotNull String name, @NotNull T defaultValue) { |
| if (defaultValue == null) { |
| return (T) get(name); |
| } |
| T value = (T)get(name, defaultValue.getClass()); |
| if (value == null) { |
| return defaultValue; |
| } |
| return value; |
| } |
| // ---- Map |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public int size() { |
| return keySet().size(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean isEmpty() { |
| if ( defaults.size() > 0 || (merge && properties.size() > 0) ) { |
| return false; |
| } |
| return size() == 0; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean containsKey(final Object key) { |
| return keySet().contains(key.toString()); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean containsValue(final Object value) { |
| return values().contains(value); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public Object get(final Object key) { |
| if (merge || defaults.containsKey(key)) { |
| // Check if property has been provided, if not use defaults |
| if (properties.containsKey(key)) { |
| return properties.get(key); |
| } else { |
| return defaults.get(key); |
| } |
| } |
| |
| // Override mode and no default value provided for this key |
| return null; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public Object put(final String aKey, final Object value) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public Object remove(final Object key) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void putAll(final Map<? extends String, ?> properties) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void clear() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public Set<String> keySet() { |
| return buildAggregatedMap().keySet(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public Collection<Object> values() { |
| return buildAggregatedMap().values(); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public Set<Entry<String, Object>> entrySet() { |
| return buildAggregatedMap().entrySet(); |
| } |
| |
| /** |
| * Build the aggregated map containing all values. |
| */ |
| private Map<String, Object> buildAggregatedMap() { |
| final Map<String, Object> entries = new HashMap<String, Object>(); |
| |
| // Add properties in merge mode or if defaults exists |
| for (final Entry<String, Object> entry : properties.entrySet()) { |
| if (merge || defaults.containsKey(entry.getKey())) { |
| entries.put(entry.getKey(), entry.getValue()); |
| } |
| } |
| |
| // Add missing defaults |
| for (final Entry<String, Object> entry : defaults.entrySet()) { |
| if ( ! entries.containsKey(entry.getKey()) ) { |
| entries.put(entry.getKey(), entry.getValue()); |
| } |
| } |
| |
| return entries; |
| } |
| } |