Java tutorial
package ca.uhn.fhir.rest.param; /* * #%L * HAPI FHIR - Core Library * %% * Copyright (C) 2014 - 2016 University Health Network * %% * Licensed 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. * #L% */ import static org.apache.commons.lang3.StringUtils.isBlank; import java.io.ByteArrayInputStream; import java.io.IOException; import java.io.InputStreamReader; import java.io.Reader; import java.lang.reflect.Method; import java.lang.reflect.Modifier; import java.nio.charset.Charset; import java.util.Collection; import java.util.List; import java.util.Map; import org.apache.commons.io.IOUtils; import org.apache.commons.lang3.Validate; import org.hl7.fhir.instance.model.api.IBaseBinary; import org.hl7.fhir.instance.model.api.IBaseResource; import ca.uhn.fhir.context.FhirContext; import ca.uhn.fhir.context.FhirVersionEnum; import ca.uhn.fhir.model.api.IResource; import ca.uhn.fhir.model.api.ResourceMetadataKeyEnum; import ca.uhn.fhir.model.api.TagList; import ca.uhn.fhir.parser.DataFormatException; import ca.uhn.fhir.parser.IParser; import ca.uhn.fhir.rest.api.RestOperationTypeEnum; import ca.uhn.fhir.rest.method.BaseMethodBinding; import ca.uhn.fhir.rest.method.IParameter; import ca.uhn.fhir.rest.method.MethodUtil; import ca.uhn.fhir.rest.method.RequestDetails; import ca.uhn.fhir.rest.server.Constants; import ca.uhn.fhir.rest.server.EncodingEnum; import ca.uhn.fhir.rest.server.IResourceProvider; import ca.uhn.fhir.rest.server.RestfulServerUtils; import ca.uhn.fhir.rest.server.exceptions.InternalErrorException; import ca.uhn.fhir.rest.server.exceptions.InvalidRequestException; public class ResourceParameter implements IParameter { private Mode myMode; private Class<? extends IBaseResource> myResourceType; public ResourceParameter(Class<? extends IResource> theParameterType, Object theProvider, Mode theMode) { Validate.notNull(theParameterType, "theParameterType can not be null"); Validate.notNull(theMode, "theMode can not be null"); myResourceType = theParameterType; myMode = theMode; Class<? extends IBaseResource> providerResourceType = null; if (theProvider instanceof IResourceProvider) { providerResourceType = ((IResourceProvider) theProvider).getResourceType(); } if (Modifier.isAbstract(myResourceType.getModifiers()) && providerResourceType != null) { myResourceType = providerResourceType; } } public Mode getMode() { return myMode; } public Class<? extends IBaseResource> getResourceType() { return myResourceType; } @Override public void initializeTypes(Method theMethod, Class<? extends Collection<?>> theOuterCollectionType, Class<? extends Collection<?>> theInnerCollectionType, Class<?> theParameterType) { // ignore for now } @Override public void translateClientArgumentIntoQueryArgument(FhirContext theContext, Object theSourceClientArgument, Map<String, List<String>> theTargetQueryArguments, IBaseResource theTargetResource) throws InternalErrorException { // TODO Auto-generated method stub } @Override public Object translateQueryParametersIntoServerArgument(RequestDetails theRequest, BaseMethodBinding<?> theMethodBinding) throws InternalErrorException, InvalidRequestException { switch (myMode) { case BODY: try { return IOUtils.toString(createRequestReader(theRequest)); } catch (IOException e) { // Shouldn't happen since we're reading from a byte array throw new InternalErrorException("Failed to load request", e); } case BODY_BYTE_ARRAY: return theRequest.loadRequestContents(); case ENCODING: return RestfulServerUtils.determineRequestEncodingNoDefault(theRequest); case RESOURCE: default: return parseResourceFromRequest(theRequest, theMethodBinding, myResourceType); } // } } public static Reader createRequestReader(RequestDetails theRequest, Charset charset) { Reader requestReader = new InputStreamReader(new ByteArrayInputStream(theRequest.loadRequestContents()), charset); return requestReader; } public static Reader createRequestReader(RequestDetails theRequest) { return createRequestReader(theRequest, determineRequestCharset(theRequest)); } public static Charset determineRequestCharset(RequestDetails theRequest) { Charset charset = theRequest.getCharset(); if (charset == null) { charset = Charset.forName("UTF-8"); } return charset; } @SuppressWarnings("unchecked") public static <T extends IBaseResource> T loadResourceFromRequest(RequestDetails theRequest, BaseMethodBinding<?> theMethodBinding, Class<T> theResourceType) { FhirContext ctx = theRequest.getServer().getFhirContext(); final Charset charset = determineRequestCharset(theRequest); Reader requestReader = createRequestReader(theRequest, charset); RestOperationTypeEnum restOperationType = theMethodBinding != null ? theMethodBinding.getRestOperationType() : null; EncodingEnum encoding = RestfulServerUtils.determineRequestEncodingNoDefault(theRequest); if (encoding == null) { String ctValue = theRequest.getHeader(Constants.HEADER_CONTENT_TYPE); if (ctValue != null) { if (ctValue.startsWith("application/x-www-form-urlencoded")) { String msg = theRequest.getServer().getFhirContext().getLocalizer().getMessage( ResourceParameter.class, "invalidContentTypeInRequest", ctValue, theMethodBinding.getRestOperationType()); throw new InvalidRequestException(msg); } } if (isBlank(ctValue)) { /* * If the client didn't send a content type, try to guess */ String body; try { body = IOUtils.toString(requestReader); } catch (IOException e) { // This shouldn't happen since we're reading from a byte array.. throw new InternalErrorException(e); } encoding = MethodUtil.detectEncodingNoDefault(body); if (encoding == null) { String msg = ctx.getLocalizer().getMessage(ResourceParameter.class, "noContentTypeInRequest", restOperationType); throw new InvalidRequestException(msg); } else { requestReader = new InputStreamReader( new ByteArrayInputStream(theRequest.loadRequestContents()), charset); } } else { String msg = ctx.getLocalizer().getMessage(ResourceParameter.class, "invalidContentTypeInRequest", ctValue, restOperationType); throw new InvalidRequestException(msg); } } IParser parser = encoding.newParser(ctx); T retVal; try { if (theResourceType != null) { retVal = parser.parseResource(theResourceType, requestReader); } else { retVal = (T) parser.parseResource(requestReader); } } catch (DataFormatException e) { String msg = ctx.getLocalizer().getMessage(ResourceParameter.class, "failedToParseRequest", encoding.name(), e.getMessage()); throw new InvalidRequestException(msg); } if (theRequest.getServer().getFhirContext().getVersion().getVersion().equals(FhirVersionEnum.DSTU1)) { TagList tagList = new TagList(); for (String nextTagComplete : theRequest.getHeaders(Constants.HEADER_CATEGORY)) { MethodUtil.parseTagValue(tagList, nextTagComplete); } if (tagList.isEmpty() == false) { ((IResource) retVal).getResourceMetadata().put(ResourceMetadataKeyEnum.TAG_LIST, tagList); } } return retVal; } public static IBaseResource parseResourceFromRequest(RequestDetails theRequest, BaseMethodBinding<?> theMethodBinding, Class<? extends IBaseResource> theResourceType) { IBaseResource retVal = null; if (IBaseBinary.class.isAssignableFrom(theResourceType)) { String ct = theRequest.getHeader(Constants.HEADER_CONTENT_TYPE); if (EncodingEnum.forContentTypeStrict(ct) == null) { FhirContext ctx = theRequest.getServer().getFhirContext(); IBaseBinary binary = (IBaseBinary) ctx.getResourceDefinition("Binary").newInstance(); binary.setContentType(ct); binary.setContent(theRequest.loadRequestContents()); retVal = binary; } } if (retVal == null) { retVal = loadResourceFromRequest(theRequest, theMethodBinding, theResourceType); } return retVal; } public enum Mode { BODY, BODY_BYTE_ARRAY, ENCODING, RESOURCE } }