All Downloads are FREE. Search and download functionalities are using the official Maven repository.

com.querydsl.jpa.hibernate.AbstractHibernateQuery Maven / Gradle / Ivy

There is a newer version: 5.1.0
Show newest version
/*
 * Copyright 2015, The Querydsl Team (http://www.querydsl.com/team)
 *
 * 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 com.querydsl.jpa.hibernate;

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.stream.Stream;

import org.jetbrains.annotations.Nullable;

import org.hibernate.*;
import org.hibernate.query.Query;

import com.mysema.commons.lang.CloseableIterator;
import com.querydsl.core.*;
import com.querydsl.core.NonUniqueResultException;
import com.querydsl.core.QueryException;
import com.querydsl.core.types.Expression;
import com.querydsl.core.types.FactoryExpression;
import com.querydsl.core.types.Path;
import com.querydsl.jpa.*;

/**
 * Abstract base class for Hibernate API based implementations of the JPQL interface
 *
 * @param  result type
 * @param  concrete subtype
 *
 * @author tiwe
 */
public abstract class AbstractHibernateQuery> extends JPAQueryBase {

    private static final Logger logger = Logger.getLogger(HibernateQuery.class.getName());

    @Nullable
    protected Boolean cacheable, readOnly;

    @Nullable
    protected String cacheRegion, comment;

    protected int fetchSize = 0;

    protected final Map,LockMode> lockModes = new HashMap,LockMode>();

    @Nullable
    protected FlushMode flushMode;

    private final SessionHolder session;

    protected int timeout = 0;

    public AbstractHibernateQuery(Session session) {
        this(new DefaultSessionHolder(session), HQLTemplates.DEFAULT, new DefaultQueryMetadata());
    }

    public AbstractHibernateQuery(SessionHolder session, JPQLTemplates patterns, QueryMetadata metadata) {
        super(metadata, patterns);
        this.session = session;
    }

    @Override
    public long fetchCount() {
        QueryModifiers modifiers = getMetadata().getModifiers();
        try {
            Query query = createQuery(modifiers, true);
            Long rv = (Long) query.uniqueResult();
            if (rv != null) {
                return rv;
            } else {
                throw new QueryException("Query returned null");
            }
        } finally {
            reset();
        }
    }

    /**
     * Expose the original Hibernate query for the given projection
     *
     * @return query
     */
    public Query createQuery() {
        return createQuery(getMetadata().getModifiers(), false);
    }

    private Query createQuery(@Nullable QueryModifiers modifiers, boolean forCount) {
        JPQLSerializer serializer = serialize(forCount);
        String queryString = serializer.toString();
        logQuery(queryString);
        Query query = session.createQuery(queryString);
        HibernateUtil.setConstants(query, serializer.getConstants(),
                getMetadata().getParams());
        if (fetchSize > 0) {
            query.setFetchSize(fetchSize);
        }
        if (timeout > 0) {
            query.setTimeout(timeout);
        }
        if (cacheable != null) {
            query.setCacheable(cacheable);
        }
        if (cacheRegion != null) {
            query.setCacheRegion(cacheRegion);
        }
        if (comment != null) {
            query.setComment(comment);
        }
        if (readOnly != null) {
            query.setReadOnly(readOnly);
        }
        for (Map.Entry, LockMode> entry : lockModes.entrySet()) {
            query.setLockMode(entry.getKey().toString(), entry.getValue());
        }
        if (flushMode != null) {
            query.setFlushMode(flushMode);
        }

        if (modifiers != null && modifiers.isRestricting()) {
            Integer limit = modifiers.getLimitAsInteger();
            Integer offset = modifiers.getOffsetAsInteger();
            if (limit != null) {
                query.setMaxResults(limit);
            }
            if (offset != null) {
                query.setFirstResult(offset);
            }
        }

        // set transformer, if necessary
        Expression projection = getMetadata().getProjection();
        if (!forCount && projection instanceof FactoryExpression) {
            query.setResultTransformer(new FactoryExpressionTransformer((FactoryExpression) projection));
        }
        return query;
    }


    /**
     * Return the query results as an {@code Iterator}. If the query
     * contains multiple results pre row, the results are returned in
     * an instance of {@code Object[]}.
*
* Entities returned as results are initialized on demand. The first * SQL query returns identifiers only.
*/ @Override public CloseableIterator iterate() { try { Query query = createQuery(); ScrollableResults results = query.scroll(ScrollMode.FORWARD_ONLY); return new ScrollableResultsIterator(results); } finally { reset(); } } @Override public Stream stream() { try { Query query = createQuery(); return query.getResultStream(); } finally { reset(); } } @Override @SuppressWarnings("unchecked") public List fetch() { try { return createQuery().list(); } finally { reset(); } } @Override public QueryResults fetchResults() { try { Query countQuery = createQuery(null, true); long total = (Long) countQuery.uniqueResult(); if (total > 0) { QueryModifiers modifiers = getMetadata().getModifiers(); Query query = createQuery(modifiers, false); @SuppressWarnings("unchecked") List list = query.list(); return new QueryResults(list, modifiers, total); } else { return QueryResults.emptyResults(); } } finally { reset(); } } protected void logQuery(String queryString) { if (logger.isLoggable(Level.FINE)) { String normalizedQuery = queryString.replace('\n', ' '); logger.fine(normalizedQuery); } } @Override protected void reset() { } /** * Return the query results as {@code ScrollableResults}. The * scrollability of the returned results depends upon JDBC driver * support for scrollable {@code ResultSet}s.
* * @param mode scroll mode * @return scrollable results */ public ScrollableResults scroll(ScrollMode mode) { try { return createQuery().scroll(mode); } finally { reset(); } } /** * Enable caching of this query result set. * @param cacheable Should the query results be cacheable? */ @SuppressWarnings("unchecked") public Q setCacheable(boolean cacheable) { this.cacheable = cacheable; return (Q) this; } /** * Set the name of the cache region. * @param cacheRegion the name of a query cache region, or {@code null} * for the default query cache */ @SuppressWarnings("unchecked") public Q setCacheRegion(String cacheRegion) { this.cacheRegion = cacheRegion; return (Q) this; } /** * Add a comment to the generated SQL. * @param comment comment * @return the current object */ @SuppressWarnings("unchecked") public Q setComment(String comment) { this.comment = comment; return (Q) this; } /** * Set a fetchJoin size for the underlying JDBC query. * @param fetchSize the fetchJoin size * @return the current object */ @SuppressWarnings("unchecked") public Q setFetchSize(int fetchSize) { this.fetchSize = fetchSize; return (Q) this; } /** * Set the lock mode for the given path. * @return the current object */ @SuppressWarnings("unchecked") public Q setLockMode(Path path, LockMode lockMode) { lockModes.put(path, lockMode); return (Q) this; } /** * Override the current session flush mode, just for this query. * @return the current object */ @SuppressWarnings("unchecked") public Q setFlushMode(FlushMode flushMode) { this.flushMode = flushMode; return (Q) this; } /** * Entities retrieved by this query will be loaded in * a read-only mode where Hibernate will never dirty-check * them or make changes persistent. * * @return the current object * */ @SuppressWarnings("unchecked") public Q setReadOnly(boolean readOnly) { this.readOnly = readOnly; return (Q) this; } /** * Set a timeout for the underlying JDBC query. * @param timeout the timeout in seconds * @return the current object */ @SuppressWarnings("unchecked") public Q setTimeout(int timeout) { this.timeout = timeout; return (Q) this; } @SuppressWarnings("unchecked") @Override public T fetchOne() throws NonUniqueResultException { try { QueryModifiers modifiers = getMetadata().getModifiers(); Query query = createQuery(modifiers, false); try { return (T) query.uniqueResult(); } catch (org.hibernate.NonUniqueResultException e) { throw new NonUniqueResultException(e); } } finally { reset(); } } @Override protected JPQLSerializer createSerializer() { return new JPQLSerializer(getTemplates()); } protected void clone(Q query) { cacheable = query.cacheable; cacheRegion = query.cacheRegion; fetchSize = query.fetchSize; flushMode = query.flushMode; lockModes.putAll(query.lockModes); readOnly = query.readOnly; timeout = query.timeout; } protected abstract Q clone(SessionHolder sessionHolder); /** * Clone the state of this query to a new instance with the given Session * * @param session session * @return cloned query */ public Q clone(Session session) { return this.clone(new DefaultSessionHolder(session)); } /** * Clone the state of this query to a new instance with the given StatelessSession * * @param session session * @return cloned query */ public Q clone(StatelessSession session) { return this.clone(new StatelessSessionHolder(session)); } /** * Clone the state of this query to a new instance * * @return closed query */ @Override public Q clone() { return this.clone(this.session); } }




© 2015 - 2024 Weber Informatics LLC | Privacy Policy