content: /**
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * 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
   * with the License.  You may obtain a copy of the License at
   * <p>
   * http://www.apache.org/licenses/LICENSE-2.0
   * <p>
   * 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 org.apache.oozie.ambari.view.repo;
  
  import java.util.Collection;
  import java.util.Date;
  
  import org.apache.ambari.view.DataStore;
  import org.apache.ambari.view.PersistenceException;
  import org.apache.oozie.ambari.view.model.Indexed;
  import org.apache.oozie.ambari.view.model.When;
  
  public class BaseRepo<T> {
  
    protected final DataStore dataStore;
    private final Class type;
  
    public BaseRepo(Class type, DataStore dataStore) {
      this.type = type;
      this.dataStore = dataStore;
    }
  
    public String generateId() {
      return java.util.UUID.randomUUID().toString();
    }
  
    public Collection<T> findAll() {
      try {
        return dataStore.findAll(type, null);
      } catch (PersistenceException e) {
        throw new RuntimeException(e);
      }
    }
  
    public T findById(String id) {
      try {
        return (T) dataStore.find(type, id);
      } catch (PersistenceException e) {
        throw new RuntimeException(e);
      }
    }
  
    public T create(T obj) {
      try {
        if (obj instanceof Indexed) {
          Indexed idxObj = (Indexed) obj;
          if (idxObj.getId() == null) {
            idxObj.setId(this.generateId());
          } else {
            T findById = findById(idxObj.getId());
            if (findById != null) {
              throw new RuntimeException("Object already exist in db");
            }
          }
        }
        if (obj instanceof When) {
          Date now = new Date();
          When when = (When) obj;
          when.setCreatedAt(String.valueOf(now.getTime()));
          when.setUpdatedAt(String.valueOf(now.getTime()));
        }
        this.dataStore.store(obj);
        return obj;
      } catch (PersistenceException e) {
        throw new RuntimeException(e);
      }
    }
  
    public void update(T obj) {
      try {
        if (obj instanceof When) {
          Date now = new Date();
          When when = (When) obj;
          when.setUpdatedAt(String.valueOf(now.getTime()));
        }
        this.dataStore.store(obj);
      } catch (PersistenceException e) {
        throw new RuntimeException(e);
      }
    }
  
    public void delete(T obj) {
      try {
        this.dataStore.remove(obj);
      } catch (PersistenceException e) {
        throw new RuntimeException(e);
      }
    }
  
    public void deleteById(String id) {
      try {
        T findById = this.findById(id);
        this.dataStore.remove(findById);
      } catch (PersistenceException e) {
        throw new RuntimeException(e);
      }
    }
  }
  