package org.luke.ct.core;
import java.lang.reflect.ParameterizedType;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Logger;
import javax.jdo.PersistenceManager;
import javax.jdo.Query;
import org.luke.ct.model.BaseEntity;
import com.google.appengine.api.datastore.Key;
import com.google.appengine.api.datastore.KeyFactory;
/**
* 以jdo方式實現的基礎數據類
*
* @since 2011/09/01 1.0
* @version 1.0
* @author kyle
*
* @param <T>
* 實體類 entity class
*/
public class DAOSupport<T extends BaseEntity> implements IDAO<T> {
// 獲得當前T的類型
protected Class<T> entityClass;// = GenericsUtil.getSuperClassGenricType(this.getClass());
// 日誌對像
private static final Logger log = Logger.getLogger(DAOSupport.class.getName());
@SuppressWarnings("unchecked")
public DAOSupport() {
// 獲得當前T的類型
this.entityClass = (Class<T>) ((ParameterizedType) getClass().getGenericSuperclass()).getActualTypeArguments()[0];
}
/**
* 添加實體
*/
public void add(T entity) {
PersistenceManager pm = PMF.get().getPersistenceManager();
try {
// 連同encodeKey一起存起來
pm.makePersistent(entity);
entity.setEncodedKey();
pm.makePersistent(entity);
log.info("add entity" + entity.getClass().getName());
} catch (Exception e) {
log.severe("添加實體 " + entity.getClass().getName() + " 時候出錯!");
log.severe(e.getMessage());
} finally {
pm.close();
}
}
/**
* 刪除實體
*/
public void delete(Key key) {
PersistenceManager pm = PMF.get().getPersistenceManager();
try {
T delEntity = pm.getObjectById(entityClass, key);
pm.deletePersistent(delEntity);
log.info("delete entity" + entityClass.getName());
} catch (Exception e) {
log.severe("刪除實體 " + entityClass.getName() + "時候出錯!");
log.severe(e.getMessage());
} finally {
pm.close();
}
}
/**
* 更新實體
*/
public void modify(T entity) {
PersistenceManager pm = PMF.get().getPersistenceManager();
try {
// 更新數據，直接調用makePersistent()方法的，要求實體類註解了如下
// @PersistenceCapable(detachable="true")
pm.makePersistent(entity);
log.info("modify entity" + entityClass.getName());
} catch (Exception e) {
log.severe("更新實體 " + entity.getClass().getName() + "時候出錯!");
log.severe(e.getMessage());
} finally {
pm.close();
}
}
/**
* @param filter
* 查詢過濾條件
* @param ordering
* 查詢後排序條件
* @param firstResult
* 開始記錄
* @param maxResult
* 檢索結果的最大數量
* @return 查詢處理好的數據
* @author kyle
*/
@SuppressWarnings("unchecked")
public QueryResult<T> getPaginationData(String filter, String ordering, long firstResult, long maxResult) {
PersistenceManager pm = PMF.get().getPersistenceManager();
QueryResult<T> qr = new QueryResult<T>();
try {
Query query = GSQLUtil.getSelectSqlStr(pm, entityClass, filter, ordering, firstResult, maxResult);
Object obj = query.execute();
if (obj != null) {
List<T> list = (List<T>) obj;
qr.setResultList(list);
// 不調用list.size()方法，那麼調用pm.close()後，再次使用list會出現Object Manager has been closed Exception
list.size();
Query queryCount = GSQLUtil.getSelectSqlStr(pm, entityClass, filter);
List<T> l = (List<T>) queryCount.execute();
qr.setTotalRecord(l.size());
} else {
qr.setResultList(new ArrayList<T>());
qr.setTotalRecord((long) 0);
}
log.info("query entity" + entityClass.getName());
} catch (Exception e) {
log.severe("查詢時候出錯了！");
log.severe(e.getMessage());
} finally {
pm.close();
}
return qr;
}
/**
* @param filter
* 查詢過濾條件
* @param odering
* 查詢後排序條件
* @return 查詢處理好的數據
* @author kyle
*/
public QueryResult<T> getPaginationData(String filter, String ordering) {
long min = -1;
return getPaginationData(filter, ordering, min, min);
}
/**
*
* @param filter
* 查詢過濾條件
* @param firstResult
* 開始記錄
* @param maxResult
* 檢索結果的最大數量
* @return 查詢處理好的數據
* @author kyle
*/
public QueryResult<T> getPaginationData(String filter, long firstResult, long maxResult) {
return getPaginationData(filter, null, firstResult, maxResult);
}
/**
*
* @param firstResult
* 開始記錄
* @param maxResult
* 檢索結果的最大數量
* @return 查詢處理好的數據
* @author kyle
*/
public QueryResult<T> getPaginationData(long firstResult, long maxResult) {
return getPaginationData(null, null, firstResult, maxResult);
}
/**
* @param filter
* 查詢過濾條件
* @return 查詢處理好的數據
* @author kyle
*/
public QueryResult<T> getPaginationData(String filter) {
return getPaginationData(filter, null);
}
/**
* @return 查詢處理好的數據
* @author kyle
*/
public QueryResult<T> getPaginationData() {
return getPaginationData(null);
}
public T getDataByID(Key key) {
PersistenceManager pm = PMF.get().getPersistenceManager();
T entity = null;
try {
entity = (T) pm.getObjectById(entityClass, key);
log.info("query entity" + entityClass.getName());
} catch (Exception e) {
log.severe("查詢時候出錯了！");
log.severe(e.getMessage());
} finally {
pm.close();
}
return entity;
}
public T getDataByID(String encodeKey) {
try {
Key key = KeyFactory.stringToKey(encodeKey);
return getDataByID(key);
} catch (IllegalArgumentException e) {
log.severe("encodeKey不合法!error:" + e.getMessage());
return null;
}
}
public T getDataByID(Long key) {
try {
Key k = KeyFactory.createKey(entityClass.getSimpleName(), key);
return getDataByID(k);
} catch (IllegalArgumentException e) {
log.severe("Long Key不合法!error:" + e.getMessage());
return null;
}
}
}