com.jvoid.persistence.hibernate.GenericHibernateDAO.java Source code

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Here is the source code for com.jvoid.persistence.hibernate.GenericHibernateDAO.java

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/*
 * #%L
 * jVoiD Open Platform
 * %%
 * Copyright 2014-2015 Schogini Systems Pvt Ltd (http://www.schogini.com)
 * Project Website: http://www.jvoid.com
 * %%
 * 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%
 */
package com.jvoid.persistence.hibernate;

import java.io.Serializable;
import java.lang.reflect.ParameterizedType;
import java.util.List;

import org.hibernate.Criteria;
import org.hibernate.LockMode;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.criterion.Criterion;
import org.hibernate.criterion.Example;
import org.springframework.beans.factory.annotation.Autowired;

import com.jvoid.persistence.persistenceapi.GenericDAO;

/**
 * Generic Hibernate DAO class
 * 
 * @author Shajir
 * @version 1.0
 */

public abstract class GenericHibernateDAO<T, ID extends Serializable> implements GenericDAO<T, ID> {

    private Class<T> persistentClass;
    @Autowired
    private SessionFactory sessionFactory;
    //   private Transaction tx;

    @SuppressWarnings("unchecked")
    public GenericHibernateDAO() {
        this.persistentClass = (Class<T>) ((ParameterizedType) getClass().getGenericSuperclass())
                .getActualTypeArguments()[0];
        //      this.tx = getSession().beginTransaction();
    }

    public void setSessionFactory(SessionFactory sessionFactory) {
        this.sessionFactory = sessionFactory;
        //        this.tx = getSession().beginTransaction();
    }

    //   public void setSession(Session s) {
    //      this.session = s;
    //   }

    protected Transaction getTransaction() {
        return getSession().getTransaction();
    }

    protected Session getSession() {
        //        if (session == null)  
        //            throw new IllegalStateException("Session has not been set on DAO before usage");  
        //        return session;  
        return this.sessionFactory.getCurrentSession();
    }

    public Class<T> getPersistentClass() {
        return persistentClass;
    }

    @SuppressWarnings("unchecked")
    @Override
    public T findById(ID id, boolean lock) {
        T entity;
        try {
            if (lock) {
                entity = (T) getSession().get(getPersistentClass(), id, LockMode.UPGRADE);
            } else {
                entity = (T) getSession().get(getPersistentClass(), id);
            }
            return entity;
        } catch (Exception e) {
            // e.printStackTrace();
            getTransaction().rollback();
            return null;
        }
    }

    @Override
    public List<T> findAll() {
        return findByCriteria();
    }

    @SuppressWarnings("unchecked")
    @Override
    public List<T> findAllByCriteria(Criterion criterion) {
        try {
            Criteria crit = getSession().createCriteria(getPersistentClass());
            crit.add(criterion);
            return crit.list();
        } catch (Exception e) {
            // e.printStackTrace();
            getTransaction().rollback();
            return null;
        }
    }

    @SuppressWarnings("unchecked")
    @Override
    public List<T> findByExample(T exampleInstance, String... excludeProperty) {
        try {
            Criteria crit = getSession().createCriteria(getPersistentClass());
            Example example = Example.create(exampleInstance);
            for (String exclude : excludeProperty) {
                example.excludeProperty(exclude);
            }
            crit.add(example);
            return crit.list();
        } catch (Exception e) {
            // e.printStackTrace();
            getTransaction().rollback();
            return null;
        }
    }

    @Override
    public T saveOrUpdate(T entity) {
        try {
            getSession().saveOrUpdate(entity);
            return entity;
        } catch (Exception e) {
            System.out.println(e.getMessage());
            e.printStackTrace();
            getTransaction().rollback();
            return null;
        }
    }

    @Override
    public void removeEntity(T entity) {
        getSession().delete(entity);
    }

    @Override
    public void flush() {
        getTransaction().commit();
        // getSession().flush();
    }

    @Override
    public void clear() {
        getSession().clear();
    }

    @SuppressWarnings("unchecked")
    protected List<T> findByCriteria(Criterion... criterion) {
        try {
            Criteria crit = getSession().createCriteria(getPersistentClass());
            for (Criterion c : criterion) {
                crit.add(c);
            }
            return crit.list();
        } catch (Exception e) {
            // e.printStackTrace();
            getTransaction().rollback();
            return null;
        }
    }
}