001/******************************************************************************* 002 * Copyright (c) 2016 Diamond Light Source Ltd. and others. 003 * All rights reserved. This program and the accompanying materials 004 * are made available under the terms of the Eclipse Public License v1.0 005 * which accompanies this distribution, and is available at 006 * http://www.eclipse.org/legal/epl-v10.html 007 * 008 * Contributors: 009 * Diamond Light Source Ltd - initial API and implementation 010 *******************************************************************************/ 011package org.eclipse.january.metadata; 012 013import java.lang.reflect.Method; 014import java.util.HashMap; 015import java.util.Map; 016 017import org.eclipse.january.MetadataException; 018import org.eclipse.january.dataset.LazyDatasetBase; 019import org.eclipse.january.metadata.internal.AxesMetadataImpl; 020import org.eclipse.january.metadata.internal.DimensionMetadataImpl; 021import org.eclipse.january.metadata.internal.ErrorMetadataImpl; 022import org.eclipse.january.metadata.internal.MaskMetadataImpl; 023import org.eclipse.january.metadata.internal.OriginMetadataImpl; 024import org.eclipse.january.metadata.internal.PeemMetadataImpl; 025import org.eclipse.january.metadata.internal.StatisticsMetadataImpl; 026import org.eclipse.january.metadata.internal.UnitMetadataImpl; 027 028public class MetadataFactory { 029 030 private MetadataFactory() { 031 } 032 033 static Map<Class<? extends MetadataType>, Class<? extends MetadataType>> metadataClasses = createMap(); 034 private static Map<Class<? extends MetadataType>, Class<? extends MetadataType>> createMap() { 035 Map<Class<? extends MetadataType>, Class<? extends MetadataType>> map = new HashMap<Class<? extends MetadataType>, Class<? extends MetadataType>>(); 036 map.put(IMetadata.class, Metadata.class); 037 map.put(ErrorMetadata.class, ErrorMetadataImpl.class); 038 map.put(AxesMetadata.class, AxesMetadataImpl.class); 039 map.put(DimensionMetadata.class, DimensionMetadataImpl.class); 040 map.put(MaskMetadata.class, MaskMetadataImpl.class); 041 map.put(OriginMetadata.class, OriginMetadataImpl.class); 042 map.put(PeemMetadata.class, PeemMetadataImpl.class); 043 map.put(StatisticsMetadata.class, StatisticsMetadataImpl.class); 044 map.put(UnitMetadata.class, UnitMetadataImpl.class); 045 return map; 046 } 047 048 049 /** 050 * Create a metadata object of given class with given arguments 051 * @param clazz 052 * @param arguments these must match the arguments given in the initialize method specified in the class 053 * @return metadata object or null if type not available 054 * @throws MetadataException if the class cannot be instantiated, the initialize method does not exist, or 055 * the initialize method could not be called successfully 056 */ 057 public static <T extends MetadataType> T createMetadata(Class<T> clazz, Object... arguments) throws MetadataException { 058 @SuppressWarnings("unchecked") 059 Class<T> mdClass = (Class<T>) metadataClasses.get(clazz); 060 if (mdClass == null) { 061 return null; 062 } 063 064 T obj = null; 065 try { 066 obj = mdClass.newInstance(); 067 } catch (Exception e) { 068 throw new MetadataException("Could not create metadata object", e); 069 } 070 071 try { 072 for (Method m : mdClass.getMethods()) { 073 if (m.getName().equals("initialize")) { 074 m.invoke(obj, arguments); 075 return obj; 076 } 077 } 078 } catch (Exception e) { 079 throw new MetadataException("Could not initialize object", e); 080 } 081 throw new MetadataException("Could not find initialize method"); 082 } 083 084 /** 085 * Register metadata class 086 * @param clazz 087 */ 088 public static <T extends MetadataType> void registerClass(Class<T> clazz) { 089 Class<? extends MetadataType> iClass = LazyDatasetBase.findMetadataTypeSubInterfaces(clazz); 090 091 metadataClasses.put(iClass, clazz); 092 } 093}