/**
* The contents of this file are subject to the license and copyright
* detailed in the LICENSE and NOTICE files at the root of the source
* tree and available online at
*
* http://www.dspace.org/license/
*/
package org.dspace.xoai.filter;
import com.lyncode.xoai.dataprovider.xml.xoaiconfig.parameters.ParameterMap;
import com.lyncode.xoai.dataprovider.xml.xoaiconfig.parameters.ParameterValue;
import com.lyncode.xoai.dataprovider.xml.xoaiconfig.parameters.SimpleType;
import org.apache.log4j.LogManager;
import org.apache.log4j.Logger;
import org.dspace.core.Constants;
import org.dspace.core.Context;
import org.dspace.xoai.data.DSpaceItem;
import org.dspace.xoai.exceptions.InvalidMetadataFieldException;
import org.dspace.xoai.filter.results.DatabaseFilterResult;
import org.dspace.xoai.filter.results.SolrFilterResult;
import org.dspace.xoai.services.api.database.FieldResolver;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
/**
* This filter allows one to retrieve (from the data source) those items
* which contains at least one metadata field value defined, it allows
* one to define multiple metadata fields to check against.
* <p/>
* One line summary: At least one metadata field defined
*
* @author Ariel J. Lira <arieljlira@gmail.com>
* @author Lyncode Development Team <dspace@lyncode.com>
*/
public class DSpaceMetadataExistsFilter extends DSpaceFilter {
private static Logger log = LogManager
.getLogger(DSpaceMetadataExistsFilter.class);
private FieldResolver fieldResolver;
private List<String> fields;
private ParameterMap configuration;
public DSpaceMetadataExistsFilter(FieldResolver fieldResolver, ParameterMap configuration) {
this.fieldResolver = fieldResolver;
this.configuration = configuration;
}
private List<String> getFields() {
if (this.fields == null) {
ParameterValue fields = getConfiguration().get("fields");
if (fields == null) fields = getConfiguration().get("field");
if (fields instanceof SimpleType) {
this.fields = new ArrayList<String>();
this.fields.add(((SimpleType) fields).asString());
} else {
this.fields = new ArrayList<String>();
for (ParameterValue val : fields.asParameterList().getValues())
this.fields.add(val.asSimpleType().asString());
}
}
return fields;
}
@Override
public DatabaseFilterResult buildDatabaseQuery(Context context) {
try {
List<String> fields = this.getFields();
StringBuilder where = new StringBuilder();
List<Object> args = new ArrayList<Object>(fields.size());
where.append("(");
for (int i = 0; i < fields.size(); i++) {
where.append("EXISTS (SELECT tmp.* FROM metadatavalue tmp WHERE tmp.resource_id=i.item_id AND tmp.resource_type_id=" + Constants.ITEM+ " AND tmp.metadata_field_id=?)");
args.add(fieldResolver.getFieldID(context, fields.get(i)));
if (i < fields.size() - 1)
where.append(" OR ");
}
where.append(")");
return new DatabaseFilterResult(where.toString(), args);
} catch (InvalidMetadataFieldException e) {
log.error(e.getMessage(), e);
} catch (SQLException e) {
log.error(e.getMessage(), e);
}
return new DatabaseFilterResult();
}
@Override
public boolean isShown(DSpaceItem item) {
for (String field : this.getFields()) {
//do we have a match? if yes, our job is done
if (item.getMetadata(field).size() > 0)
return true;
}
return false;
}
@Override
public SolrFilterResult buildSolrQuery() {
StringBuilder cond = new StringBuilder("(");
List<String> fields = this.getFields();
for (int i = 0; i < fields.size(); i++) {
cond.append("metadata.").append(fields.get(i)).append(":[* TO *]");
if (i < fields.size() - 1)
cond.append(" OR ");
}
cond.append(")");
return new SolrFilterResult(cond.toString());
}
public ParameterMap getConfiguration() {
return configuration;
}
}