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* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
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*
* 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
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package org.apache.olingo.odata2.jpa.processor.core.jpql;
import java.util.List;
import org.apache.olingo.odata2.jpa.processor.api.access.JPAJoinClause;
import org.apache.olingo.odata2.jpa.processor.api.exception.ODataJPARuntimeException;
import org.apache.olingo.odata2.jpa.processor.api.jpql.JPQLContextView;
import org.apache.olingo.odata2.jpa.processor.api.jpql.JPQLJoinSelectSingleContextView;
import org.apache.olingo.odata2.jpa.processor.api.jpql.JPQLStatement;
import org.apache.olingo.odata2.jpa.processor.api.jpql.JPQLStatement.JPQLStatementBuilder;
public class JPQLJoinSelectSingleStatementBuilder extends JPQLStatementBuilder {
JPQLStatement jpqlStatement;
private JPQLJoinSelectSingleContextView context;
public JPQLJoinSelectSingleStatementBuilder(final JPQLContextView context) {
this.context = (JPQLJoinSelectSingleContextView) context;
}
@Override
public JPQLStatement build() throws ODataJPARuntimeException {
jpqlStatement = createStatement(createJPQLQuery());
return jpqlStatement;
}
private String createJPQLQuery() throws ODataJPARuntimeException {
StringBuilder jpqlQuery = new StringBuilder();
StringBuilder joinWhereCondition = null;
jpqlQuery.append(JPQLStatement.KEYWORD.SELECT).append(JPQLStatement.DELIMITER.SPACE);
jpqlQuery.append(context.getSelectExpression()).append(JPQLStatement.DELIMITER.SPACE);
jpqlQuery.append(JPQLStatement.KEYWORD.FROM).append(JPQLStatement.DELIMITER.SPACE);
if (context.getJPAJoinClauses() != null && context.getJPAJoinClauses().size() > 0) {
List<JPAJoinClause> joinClauseList = context.getJPAJoinClauses();
JPAJoinClause joinClause = joinClauseList.get(0);
String joinCondition = joinClause.getJoinCondition();
joinWhereCondition = new StringBuilder();
if (joinCondition != null) {
joinWhereCondition.append(joinCondition);
}
String relationShipAlias = null;
joinClause = joinClauseList.get(1);
jpqlQuery.append(joinClause.getEntityName()).append(JPQLStatement.DELIMITER.SPACE);
jpqlQuery.append(joinClause.getEntityAlias());
int i = 1;
int limit = joinClauseList.size();
relationShipAlias = joinClause.getEntityAlias();
while (i < limit) {
jpqlQuery.append(JPQLStatement.DELIMITER.SPACE);
jpqlQuery.append(JPQLStatement.KEYWORD.JOIN).append(JPQLStatement.DELIMITER.SPACE);
joinClause = joinClauseList.get(i);
jpqlQuery.append(relationShipAlias).append(JPQLStatement.DELIMITER.PERIOD);
jpqlQuery.append(joinClause.getEntityRelationShip()).append(JPQLStatement.DELIMITER.SPACE);
jpqlQuery.append(joinClause.getEntityRelationShipAlias());
relationShipAlias = joinClause.getEntityRelationShipAlias();
i++;
joinCondition = joinClause.getJoinCondition();
if (joinCondition != null) {
joinWhereCondition.append(JPQLStatement.DELIMITER.SPACE + JPQLStatement.Operator.AND
+ JPQLStatement.DELIMITER.SPACE);
joinWhereCondition.append(joinCondition);
}
}
} else {
throw ODataJPARuntimeException.throwException(ODataJPARuntimeException.JOIN_CLAUSE_EXPECTED, null);
}
if (joinWhereCondition.length() > 0) {
jpqlQuery.append(JPQLStatement.DELIMITER.SPACE);
jpqlQuery.append(JPQLStatement.KEYWORD.WHERE).append(JPQLStatement.DELIMITER.SPACE);
jpqlQuery.append(joinWhereCondition.toString());
}
return jpqlQuery.toString();
}
}