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/* * Copyright 2015 DuraSpace, Inc. * * 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. */ package org.fcrepo.kernel.modeshape.utils; import static java.util.Arrays.asList; import static java.util.Arrays.stream; import static org.fcrepo.kernel.modeshape.utils.FedoraTypesUtils.getReferencePropertyName; import static org.fcrepo.kernel.modeshape.utils.FedoraTypesUtils.isExternalNode; import static org.fcrepo.kernel.modeshape.utils.FedoraTypesUtils.isInternalReferenceProperty; import static org.fcrepo.kernel.modeshape.utils.FedoraTypesUtils.isMultivaluedProperty; import static org.fcrepo.kernel.modeshape.utils.UncheckedPredicate.uncheck; import static org.slf4j.LoggerFactory.getLogger; import java.util.ArrayList; import java.util.List; import java.util.concurrent.atomic.AtomicBoolean; import org.apache.commons.lang3.StringUtils; import javax.jcr.Node; import javax.jcr.Property; import javax.jcr.PropertyType; import javax.jcr.RepositoryException; import javax.jcr.Value; import com.hp.hpl.jena.rdf.model.Resource; import org.fcrepo.kernel.api.models.FedoraResource; import org.fcrepo.kernel.api.exception.IdentifierConversionException; import org.fcrepo.kernel.api.exception.NoSuchPropertyDefinitionException; import org.fcrepo.kernel.api.identifiers.IdentifierConverter; import org.slf4j.Logger; /** * Tools for replacing, appending and deleting JCR node properties * @author Chris Beer * @author ajs6f * @since May 10, 2013 */ public class NodePropertiesTools { private static final Logger LOGGER = getLogger(NodePropertiesTools.class); /** * Given a JCR node, property and value, either: * - if the property is single-valued, replace the existing property with * the new value * - if the property is multivalued, append the new value to the property * @param node the JCR node * @param propertyName a name of a JCR property (either pre-existing or * otherwise) * @param newValue the JCR value to insert * @throws RepositoryException if repository exception occurred */ public void appendOrReplaceNodeProperty(final Node node, final String propertyName, final Value newValue) throws RepositoryException { final Property property; // if it already exists, we can take some shortcuts if (node.hasProperty(propertyName)) { property = node.getProperty(propertyName); if (property.isMultiple()) { LOGGER.debug("Appending value {} to {} property {}", newValue, PropertyType.nameFromValue(property.getType()), propertyName); // if the property is multi-valued, go ahead and append to it. final List<Value> newValues = new ArrayList<>(asList(node.getProperty(propertyName).getValues())); if (!newValues.contains(newValue)) { newValues.add(newValue); property.setValue(newValues.toArray(new Value[newValues.size()])); } } else { // or we'll just overwrite its single value LOGGER.debug("Overwriting {} property {} with new value {}", PropertyType.nameFromValue(property.getType()), propertyName, newValue); property.setValue(newValue); } } else { // we're creating a new property on this node, so we check whether it should be multi-valued boolean isMultiple = true; try { isMultiple = isMultivaluedProperty(node, propertyName); } catch (final NoSuchPropertyDefinitionException e) { // simply represents a new kind of property on this node } if (isMultiple) { LOGGER.debug("Creating new multivalued {} property {} with " + "initial value [{}]", PropertyType.nameFromValue(newValue.getType()), propertyName, newValue); property = node.setProperty(propertyName, new Value[] { newValue }, newValue.getType()); } else { LOGGER.debug("Creating new single-valued {} property {} with " + "initial value {}", PropertyType.nameFromValue(newValue.getType()), propertyName, newValue); property = node.setProperty(propertyName, newValue, newValue.getType()); } } if (!property.isMultiple() && !isInternalReferenceProperty.test(property)) { final String referencePropertyName = getReferencePropertyName(propertyName); if (node.hasProperty(referencePropertyName)) { node.getProperty(referencePropertyName).remove(); } } } /** * Add a reference placeholder from one node to another in-domain resource * @param idTranslator the id translator * @param node the node * @param propertyName the property name * @param resource the resource * @throws RepositoryException if repository exception occurred */ public void addReferencePlaceholders(final IdentifierConverter<Resource, FedoraResource> idTranslator, final Node node, final String propertyName, final Resource resource) throws RepositoryException { try { final Node refNode = idTranslator.convert(resource).getNode(); if (isExternalNode.test(refNode)) { // we can't apply REFERENCE properties to external resources return; } final String referencePropertyName = getReferencePropertyName(propertyName); if (!isMultivaluedProperty(node, propertyName)) { if (node.hasProperty(referencePropertyName)) { node.getProperty(referencePropertyName).remove(); } if (node.hasProperty(propertyName)) { node.getProperty(propertyName).remove(); } } final Value v = node.getSession().getValueFactory().createValue(refNode, true); appendOrReplaceNodeProperty(node, referencePropertyName, v); } catch (final IdentifierConversionException e) { // no-op } } /** * Remove a reference placeholder that links one node to another in-domain resource * @param idTranslator the id translator * @param node the node * @param propertyName the property name * @param resource the resource * @throws RepositoryException if repository exception occurred */ public void removeReferencePlaceholders(final IdentifierConverter<Resource, FedoraResource> idTranslator, final Node node, final String propertyName, final Resource resource) throws RepositoryException { final String referencePropertyName = getReferencePropertyName(propertyName); final Node refNode = idTranslator.convert(resource).getNode(); final Value v = node.getSession().getValueFactory().createValue(refNode, true); removeNodeProperty(node, referencePropertyName, v); } /** * Given a JCR node, property and value, remove the value (if it exists) * from the property, and remove the * property if no values remove * * @param node the JCR node * @param propertyName a name of a JCR property (either pre-existing or * otherwise) * @param valueToRemove the JCR value to remove * @throws RepositoryException if repository exception occurred */ public void removeNodeProperty(final Node node, final String propertyName, final Value valueToRemove) throws RepositoryException { LOGGER.debug("Request to remove {}", valueToRemove); // if the property doesn't exist, we don't need to worry about it. if (node.hasProperty(propertyName)) { final Property property = node.getProperty(propertyName); final String strValueToRemove = valueToRemove.getString(); if (property.isMultiple()) { final AtomicBoolean remove = new AtomicBoolean(); final Value[] newValues = stream(node.getProperty(propertyName).getValues()).filter(uncheck(v -> { final String strVal = v.getString(); LOGGER.debug("v is '{}', valueToRemove is '{}'", v, strValueToRemove); if (strVal.equals(strValueToRemove)) { remove.set(true); return false; } return true; })).toArray(Value[]::new); // we only need to update the property if we did anything. if (remove.get()) { if (newValues.length == 0) { LOGGER.debug("Removing property '{}'", propertyName); property.remove(); } else { LOGGER.debug("Removing value '{}' from property '{}'", strValueToRemove, propertyName); property.setValue(newValues); } } else { LOGGER.debug("Value not removed from property name '{}' (value '{}')", propertyName, strValueToRemove); throw new RepositoryException("Property '" + propertyName + "': Unable to remove value '" + StringUtils.substring(strValueToRemove, 0, 50) + "...'"); } } else { final String strPropVal = property.getValue().getString(); LOGGER.debug("Removing string '{}'", strValueToRemove); if (StringUtils.equals(strPropVal, strValueToRemove)) { LOGGER.debug("single value: Removing value from property '{}'", propertyName); property.remove(); } else { LOGGER.debug( "Value not removed from property name '{}' (property value: '{}';compare value: '{}')", propertyName, strPropVal, strValueToRemove); throw new RepositoryException("Property '" + propertyName + "': Unable to remove value '" + StringUtils.substring(strValueToRemove, 0, 50) + "'"); } } } } }