ca.uhn.fhir.rest.method.ElementsParameter.java Source code

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Here is the source code for ca.uhn.fhir.rest.method.ElementsParameter.java

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package ca.uhn.fhir.rest.method;

/*
 * #%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.isNotBlank;

import java.lang.reflect.Method;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.StringTokenizer;

import org.apache.commons.lang3.StringUtils;
import org.hl7.fhir.instance.model.api.IBaseResource;

import ca.uhn.fhir.context.ConfigurationException;
import ca.uhn.fhir.context.FhirContext;
import ca.uhn.fhir.rest.api.SummaryEnum;
import ca.uhn.fhir.rest.param.CollectionBinder;
import ca.uhn.fhir.rest.server.Constants;
import ca.uhn.fhir.rest.server.exceptions.InternalErrorException;
import ca.uhn.fhir.rest.server.exceptions.InvalidRequestException;

public class ElementsParameter implements IParameter {

    @SuppressWarnings("rawtypes")
    private Class<? extends Collection> myInnerCollectionType;

    @SuppressWarnings("unchecked")
    @Override
    public void translateClientArgumentIntoQueryArgument(FhirContext theContext, Object theSourceClientArgument,
            Map<String, List<String>> theTargetQueryArguments, IBaseResource theTargetResource)
            throws InternalErrorException {
        if (theSourceClientArgument instanceof Collection) {
            StringBuilder values = new StringBuilder();
            for (String next : (Collection<String>) theSourceClientArgument) {
                if (isNotBlank(next)) {
                    if (values.length() > 0) {
                        values.append(',');
                    }
                    values.append(next);
                }
            }
            theTargetQueryArguments.put(Constants.PARAM_ELEMENTS, Collections.singletonList(values.toString()));
        } else {
            String elements = (String) theSourceClientArgument;
            if (elements != null) {
                theTargetQueryArguments.put(Constants.PARAM_ELEMENTS, Collections.singletonList(elements));
            }
        }
    }

    @Override
    @SuppressWarnings({ "rawtypes", "unchecked" })
    public Object translateQueryParametersIntoServerArgument(RequestDetails theRequest,
            BaseMethodBinding<?> theMethodBinding) throws InternalErrorException, InvalidRequestException {
        Set<String> value = getElementsValueOrNull(theRequest);
        if (value == null || value.isEmpty()) {
            return null;
        }

        if (myInnerCollectionType == null) {
            return StringUtils.join(value, ',');
        }

        try {
            Collection retVal = myInnerCollectionType.newInstance();
            retVal.addAll(value);
            return retVal;
        } catch (InstantiationException e) {
            throw new InternalErrorException("Failed to instantiate " + myInnerCollectionType, e);
        } catch (IllegalAccessException e) {
            throw new InternalErrorException("Failed to instantiate " + myInnerCollectionType, e);
        }
    }

    public static Set<String> getElementsValueOrNull(RequestDetails theRequest) {
        String[] summary = theRequest.getParameters().get(Constants.PARAM_ELEMENTS);

        if (summary != null && summary.length > 0) {
            Set<String> retVal = new HashSet<String>();
            for (String next : summary) {
                StringTokenizer tok = new StringTokenizer(next, ",");
                while (tok.hasMoreTokens()) {
                    String token = tok.nextToken();
                    if (isNotBlank(token)) {
                        retVal.add(token);
                    }
                }
            }
            if (retVal.isEmpty()) {
                return null;
            }

            // Always include the meta element even for subsetted values
            retVal.add("meta");

            return retVal;
        } else {
            return null;
        }
    }

    @Override
    public void initializeTypes(Method theMethod, Class<? extends Collection<?>> theOuterCollectionType,
            Class<? extends Collection<?>> theInnerCollectionType, Class<?> theParameterType) {
        if (theOuterCollectionType != null) {
            throw new ConfigurationException("Method '" + theMethod.getName() + "' in type '"
                    + theMethod.getDeclaringClass().getCanonicalName() + "' is of type " + SummaryEnum.class
                    + " but can not be a collection of collections");
        }
        if (theInnerCollectionType != null) {
            myInnerCollectionType = CollectionBinder.getInstantiableCollectionType(theInnerCollectionType,
                    SummaryEnum.class.getSimpleName());
        }
    }

}