AbstractRepository.java

/*
 * Name:        AbstractRepository
 * Purpose:     To abstract out the Repository interface so that each implementation (ex: UserRepository)
 *              doesn't have to implement every method.
 *
 */
package com.example.dao;

import com.example.struts.utilities.HibernateUtil;
import java.util.ArrayList;
import java.util.List;
import org.hibernate.Query;


import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;

/**
 *
 * @author Cecil.Meeks
 */
public abstract class AbstractRepository<T> implements Repository<T> {

   String errorMessage = "Not supported yet";
   String className = "";
   List<Like> likeList;

   public void SetClassName(String className) {
      this.className = className;
      this.likeList = new ArrayList<Like>();
   }

   public String GetClassName() {
      return this.className;
   }

   // Session factory and sessions
   public SessionFactory getSessionFactory() {
      SessionFactory factory = HibernateUtil.getSessionFactory();
      return factory;
   }

   public Session getSessionFromFactory() {
      return getSessionFactory().getCurrentSession();
   }

   // Query building
   public AbstractRepository<T> like(String column, String value) {
      if (likeList != null) {
         likeList.add(new Like(column, value));
      }
      return this;
   }

   public List<T> select() {
      List<T> objects = new ArrayList<T>();
      String hql = "from " + className + " " + className.toLowerCase();

      try {
         Session session = getSessionFromFactory();
         Transaction trans = session.getTransaction();
         trans.begin();

         // Build LIKE
         hql += BuildLIKEString(hql);

         // Build query
         Query query = session.createQuery(hql);

         // Set parameters
         if (likeList.size() > 0) {
            for (Like like : likeList) {
               query.setParameter(like.getColumnName(), like.getValue());
            }
         }

         objects = query.list();
         trans.commit();
         
      } catch (Exception ex) {
         for(StackTraceElement elem : ex.getStackTrace()){
            System.out.println("StackTrace Element (Exception): " + elem.toString());
            System.out.println("StackTrace Element (Class Name): " + elem.getClassName());
            System.out.println("StackTrace Element (Method Name): " + elem.getMethodName());
            System.out.println("StackTrace Element (Line Number): " + elem.getLineNumber());
         }
      }
      return objects;
   }

   private String BuildLIKEString(String queryString) {
      String qs = "";
      boolean first = true;

      if (likeList.size() > 0) {
         for (Like like : likeList) {
            if (first) {
               first = false;
               qs += " where ";
            } else {
               qs += " and ";
            }

            qs += className.toLowerCase() + "." + like.getColumnName() + " like :" + like.getColumnName();
         }
      }

      return qs;
   }

// Fetching shortcuts
   public Object first() {
      throw new UnsupportedOperationException(errorMessage);
   }

   public List<T> findAll() {
      throw new UnsupportedOperationException(errorMessage);

   }

   // Insert / Updates
   public int insert(Object dataBean) {
      Integer ret = 0;

      Session session = getSessionFromFactory();
      session.beginTransaction();
      Transaction trans = session.getTransaction();

      try {
         session.save(dataBean);
         trans.commit();
      } catch (Exception ex) {
         trans.rollback();
         ret = -1;
      }
      return ret;
   }

   public int update(Object dataBean) {
      Integer ret = 0;

      Session session = getSessionFromFactory();
      session.beginTransaction();
      Transaction trans = session.getTransaction();

      try {
         session.update(dataBean);
         trans.commit();
      } catch (Exception ex) {
         trans.rollback();
         ret = -1;
      }
      return ret;
   }

   public int delete(Object dataBean) {
      Integer ret = 0;

      Session session = getSessionFromFactory();
      session.beginTransaction();
      Transaction trans = session.getTransaction();

      try {
         session.delete(dataBean);
         trans.commit();
      } catch (Exception ex) {
         trans.rollback();
         ret = -1;
      }
      return ret;
   }
}

StackTrace.log

StackTrace Element (Exception): $Proxy0.createQuery(Unknown Source)
StackTrace Element (Class Name): $Proxy0
StackTrace Element (Method Name): createQuery
StackTrace Element (Line Number): -1
StackTrace Element (Exception): com.example.dao.AbstractRepository.select(AbstractRepository.java:71)
StackTrace Element (Class Name): com.example.dao.AbstractRepository
StackTrace Element (Method Name): select
StackTrace Element (Line Number): 71
StackTrace Element (Exception): com.example.models.TestSites.main(TestSites.java:52)
StackTrace Element (Class Name): com.example.models.TestSites
StackTrace Element (Method Name): main
StackTrace Element (Line Number): 52

State.java

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package com.example.models;

import java.util.UUID;

/**
 *
 * @author Cecil.Meeks
 */
public class State {

    private String stateKey;
    private String stateCode;
    private String name;
    private String countryCodeKey;
    private String accountingStateCode;

    public State() {
    }
    // ---------------------------------------------------------------------------------------------------------
    // ID (Key)
    // ---------------------------------------------------------------------------------------------------------
    public String getStateKey() {
        return stateKey;
    }

    private void setStateKey(String stateKey) {
        this.stateKey = stateKey;
    }


    // ---------------------------------------------------------------------------------------------------------
    // StateCode
    // ---------------------------------------------------------------------------------------------------------
    public String getStateCode() {
        return stateCode;
    }

    public void setStateCode(String stateCode) {
        this.stateCode = stateCode;
    }

    // ---------------------------------------------------------------------------------------------------------
    // Name
    // ---------------------------------------------------------------------------------------------------------
    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    // ---------------------------------------------------------------------------------------------------------
    // CountryCodeKey
    // ---------------------------------------------------------------------------------------------------------
    public String getCountryCodeKey() {
        return countryCodeKey;
    }

    public UUID getCountryCodeKeyAsUUID() {
        return UUID.fromString( countryCodeKey );
    }

    public void setCountryCodeKey(String countryCodeKey) {
        this.countryCodeKey = countryCodeKey;
    }

    // ---------------------------------------------------------------------------------------------------------
    // AccountingStateCode
    // ---------------------------------------------------------------------------------------------------------
    public String getAccountingStateCode() {
        return accountingStateCode;
    }

    public void setAccountingStateCode(String accountingStateCode) {
        this.accountingStateCode = accountingStateCode;
    }
}

TestStates.java

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package com.example.models;

import com.example.dao.repositories.*;
import java.util.List;
import java.util.UUID;

/**
 *
 * @author Cecil.Meeks
 */
public class TestSites {

    public static void main(String[] args) {

        StateRepository stateRepo = new StateRepository();

        // Example 4
        // Search for states using LIKE
        // List<State> states = stateRepo.like("StateCode", "T%").select()

        List<State> states = stateRepo.like("StateCode", "%TN").select();

        System.out.println("Count: " + states.size() );

        for(State state : states){
           System.out.println("State: " + state.getName());
        }        

    }
}