Java tutorial
/* * 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.nosql.generic.resource.impl; import java.io.ByteArrayInputStream; import java.io.IOException; import java.io.InputStream; import java.util.Calendar; import java.util.Date; import java.util.Map; import org.apache.commons.io.IOUtils; import org.apache.sling.api.resource.ModifiableValueMap; import org.apache.sling.api.resource.Resource; import org.apache.sling.api.wrappers.ValueMapDecorator; /** * Enhances ValueMap that adds special support for deep path access. * Additionally date and binary types are converted to string and back when reading. * Besides this only primitive types String, Integer, Long, Double, Boolean and arrays of them are supported. */ class NoSqlValueMap extends ValueMapDecorator implements ModifiableValueMap { private final Resource resource; private final NoSqlResourceProvider resourceProvider; public NoSqlValueMap(Map<String, Object> map, Resource resource, NoSqlResourceProvider resourceProvider) { super(convertForWriteAll(map)); this.resource = resource; this.resourceProvider = resourceProvider; } @SuppressWarnings("unchecked") @Override public <T> T get(String name, Class<T> type) { if (type == Date.class) { Calendar value = get(name, Calendar.class); if (value != null) { return (T) value.getTime(); } } else if (type == InputStream.class) { // Support conversion from byte array to InputStream byte[] data = get(name, byte[].class); if (data != null) { return (T) new ByteArrayInputStream(data); } else { return null; } } else if (type == null) { return (T) super.get(name); } return super.get(name, type); } @Override public Object put(String key, Object value) { Object result = super.put(key, convertForWrite(value)); resourceProvider.markAsChanged(resource); return result; } @SuppressWarnings("unchecked") @Override public void putAll(Map<? extends String, ?> map) { super.putAll((Map<? extends String, ?>) convertForWriteAll((Map<String, Object>) map)); resourceProvider.markAsChanged(resource); } @Override public Object remove(Object key) { Object result = super.remove(key); resourceProvider.markAsChanged(resource); return result; } @Override public void clear() { super.clear(); resourceProvider.markAsChanged(resource); } private static Object convertForWrite(Object value) { if (value instanceof Date) { Calendar calendar = Calendar.getInstance(); calendar.setTime((Date) value); value = calendar; } else if (value instanceof InputStream) { // Store InputStream values as byte array try { value = convertForWrite(IOUtils.toByteArray((InputStream) value)); } catch (IOException ex) { throw new RuntimeException("Unable to convert input stream to byte array."); } } else if (value != null && !isValidType(value.getClass())) { throw new IllegalArgumentException("Data type not supported for NoSqlValueMap: " + value.getClass()); } return value; } static boolean isValidType(Class clazz) { if (clazz.isArray()) { if (clazz.getComponentType() == byte.class) { // byte only supported as array return true; } return isValidType(clazz.getComponentType()); } else { return clazz == String.class || clazz == Integer.class || clazz == Long.class || clazz == Double.class || clazz == Boolean.class || Calendar.class.isAssignableFrom(clazz); } } public static Map<String, Object> convertForWriteAll(Map<String, Object> map) { for (Map.Entry<String, Object> entry : map.entrySet()) { map.put(entry.getKey(), convertForWrite(entry.getValue())); } return map; } }