edu.harvard.med.iccbl.dev.HibernateConsole.java Source code

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Here is the source code for edu.harvard.med.iccbl.dev.HibernateConsole.java

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// $HeadURL$
// $Id$
//
// Copyright  2006, 2010, 2011, 2012 by the President and Fellows of Harvard College.
// 
// Screensaver is an open-source project developed by the ICCB-L and NSRB labs
// at Harvard Medical School. This software is distributed under the terms of
// the GNU General Public License.

package edu.harvard.med.iccbl.dev;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;

import org.apache.commons.io.IOUtils;
import org.apache.log4j.Logger;
import org.hibernate.Session;

import edu.harvard.med.screensaver.io.CommandLineApplication;
import edu.harvard.med.screensaver.util.StringUtils;

/**
 * A command-line application for issuing HQL queries to a Screensaver database.
 *
 * @author <a mailto="andrew_tolopko@hms.harvard.edu">Andrew Tolopko</a>
 * @author <a mailto="john_sullivan@hms.harvard.edu">John Sullivan</a>
 */
public class HibernateConsole {
    private static Logger log = Logger.getLogger(HibernateConsole.class);

    public static void main(String[] args) {
        BufferedReader br = null;
        try {
            CommandLineApplication app = new CommandLineApplication(args);
            app.processOptions(true, false);
            br = new BufferedReader(new InputStreamReader(System.in));

            EntityManagerFactory emf = (EntityManagerFactory) app.getSpringBean("entityManagerFactory");
            EntityManager em = emf.createEntityManager();

            do {
                System.out.println("Enter HQL query (blank to quit): ");
                String input = br.readLine();
                if (input.length() == 0) {
                    System.out.println("Goodbye!");
                    System.exit(0);
                }
                try {
                    List list = ((Session) em.getDelegate()).createQuery(input).list(); // note: this uses the Hibernate Session object, to allow HQL (and JPQL)
                    // List list = em.createQuery(input).getResultList();  // note: this JPA method supports JPQL

                    System.out.println("Result:");
                    for (Iterator iter = list.iterator(); iter.hasNext();) {
                        Object item = iter.next();
                        // format output from multi-item selects ("select a, b, c, ... from ...")
                        if (item instanceof Object[]) {
                            List<Object> fields = Arrays.asList((Object[]) item);
                            System.out.println(StringUtils.makeListString(fields, ", "));
                        }
                        // format output from single-item selected ("select a from ..." or "from ...")
                        else {
                            System.out.println("[" + item.getClass().getName() + "]: " + item);
                        }
                    }
                    System.out.println("(" + list.size() + " rows)\n");
                } catch (Exception e) {
                    System.out.println("Hibernate Error: " + e.getMessage());
                    log.error("Hibernate error", e);
                }
                System.out.println();
            } while (true);
        } catch (Exception e) {
            System.err.println("Fatal Error: " + e.getMessage());
            e.printStackTrace();
        } finally {
            IOUtils.closeQuietly(br);
        }
    }

}