Java tutorial
package org.bimserver.shared.pb; /****************************************************************************** * Copyright (C) 2009-2012 BIMserver.org * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as * published by the Free Software Foundation, either version 3 of the * License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Affero General Public License for more details. * * You should have received a copy of the GNU Affero General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. *****************************************************************************/ import java.io.ByteArrayOutputStream; import java.io.IOException; import java.util.ArrayList; import java.util.Collection; import java.util.Date; import java.util.HashSet; import java.util.Iterator; import java.util.List; import java.util.Set; import javax.activation.DataHandler; import org.apache.commons.io.IOUtils; import org.bimserver.shared.exceptions.ServerException; import org.bimserver.shared.exceptions.UserException; import org.bimserver.shared.meta.SBase; import org.bimserver.shared.meta.SMethod; import org.bimserver.shared.meta.SService; import org.bimserver.shared.pb.ProtocolBuffersMetaData.MethodDescriptorContainer; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.google.protobuf.ByteString; import com.google.protobuf.Descriptors.Descriptor; import com.google.protobuf.Descriptors.EnumDescriptor; import com.google.protobuf.Descriptors.FieldDescriptor; import com.google.protobuf.Descriptors.FieldDescriptor.JavaType; import com.google.protobuf.DynamicMessage; import com.google.protobuf.DynamicMessage.Builder; import com.google.protobuf.Message; import com.google.protobuf.ServiceException; public class Reflector extends ProtocolBuffersConverter { private static final Logger LOGGER = LoggerFactory.getLogger(Reflector.class); private final ProtocolBuffersMetaData protocolBuffersMetaData; private final Channel channel; private final SService sService; public Reflector(ProtocolBuffersMetaData protocolBuffersMetaData, SService sService, Channel channel) { super(sService, protocolBuffersMetaData); this.protocolBuffersMetaData = protocolBuffersMetaData; this.sService = sService; this.channel = channel; } @SuppressWarnings({ "rawtypes", "unchecked" }) public Object callMethod(String interfaceName, String methodName, Class<?> definedReturnType, Object... args) throws ServerException, UserException { try { MethodDescriptorContainer methodDescriptorContainer = protocolBuffersMetaData.getMethod(interfaceName, methodName); SMethod sMethod = sService.getSMethod(methodName); Descriptor inputDescriptor = methodDescriptorContainer.getInputDescriptor(); Builder builder = DynamicMessage.newBuilder(methodDescriptorContainer.getInputDescriptor()); int i = 0; for (FieldDescriptor field : inputDescriptor.getFields()) { Object arg = args[i]; if (field.getJavaType() == JavaType.ENUM) { EnumDescriptor enumType = field.getEnumType(); builder.setField(field, enumType.findValueByName(arg.toString())); } else { if (arg instanceof SBase) { builder.setField(field, convertSObjectToProtocolBuffersObject((SBase) arg, sMethod.getParameter(i).getType())); } else if (arg instanceof DataHandler) { DataHandler dataHandler = (DataHandler) arg; ByteArrayOutputStream baos = new ByteArrayOutputStream(); try { IOUtils.copy(dataHandler.getInputStream(), baos); } catch (IOException e) { LOGGER.error("", e); } builder.setField(field, ByteString.copyFrom(baos.toByteArray())); } else { if (arg != null) { if (arg instanceof Collection) { Collection col = (Collection) arg; Iterator iterator = col.iterator(); while (iterator.hasNext()) { Object o = iterator.next(); builder.addRepeatedField(field, o); } } else { builder.setField(field, arg); } } } } i++; } DynamicMessage message = builder.build(); Message result = channel.callBlockingMethod(methodDescriptorContainer, message); FieldDescriptor errorMessageField = methodDescriptorContainer.getOutputField("errorMessage"); String errorMessage = (String) result.getField(errorMessageField); if (errorMessage.equals("OKE")) { if (result.getDescriptorForType().getName().equals("VoidResponse")) { return null; } else { FieldDescriptor outputField = methodDescriptorContainer.getOutputField("value"); Object value = result.getField(outputField); if (outputField.isRepeated()) { if (value instanceof Collection) { Collection collection = (Collection) value; Collection x = null; if (definedReturnType == List.class) { x = new ArrayList(); } else if (definedReturnType == Set.class) { x = new HashSet(); } for (Object v : collection) { if (v instanceof DynamicMessage) { x.add(convertProtocolBuffersMessageToSObject((DynamicMessage) v, null, sMethod.getBestReturnType())); } else { x.add(v); } } return x; } else { return new ArrayList(); } } else if (outputField.getJavaType() == JavaType.ENUM) { EnumDescriptor enumType = outputField.getEnumType(); return enumType.findValueByName(value.toString()); } else if (value instanceof DynamicMessage) { return convertProtocolBuffersMessageToSObject((DynamicMessage) value, null, sMethod.getBestReturnType()); } else { if (definedReturnType == Date.class) { return new Date((Long) value); } return value; } } } else { throw new UserException(errorMessage); } } catch (ConvertException e) { throw new ServerException(e); } catch (ServiceException e) { throw new ServerException(e.getMessage()); } } }