1 /*

     2  * Copyright (c) 2007-2008 Nokia Corporation and/or its subsidiary(-ies).

     3  * All rights reserved.

     4  * This component and the accompanying materials are made available

     5  * under the terms of the License "Eclipse Public License v1.0"

     6  * which accompanies this distribution, and is available

     7  * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8  *

     9  * Initial Contributors:

    10  * Nokia Corporation - initial contribution.

    11  *

    12  * Contributors:

    13  *

    14  * Description:  

    15  *

    16  */

    17 

    18 package com.nokia.helium.metadata.ant.types;

    19 

    20 import java.util.Hashtable;

    21 import java.util.Map;

    22 

    23 import javax.persistence.EntityManager;

    24 

    25 import com.nokia.helium.metadata.model.metadata.Component;

    26 import com.nokia.helium.metadata.model.metadata.LogFile;

    27 

    28 /**

    29  * LogMetaDataInput which implements some abstract component handling. 

    30  *

    31  */

    32 public abstract class AbstractComponentBaseMetadataInput extends LogMetaDataInput {

    33     protected static final String DEFAULT_COMPONENT = "Default";

    34     private Map<String, Component> components = new Hashtable<String, Component>();

    35     private Component defaultComponent;

    36     

    37     /**

    38      * Provides an entity manager to manipulate the data.

    39      * @return

    40      */

    41     protected abstract EntityManager getEntityManager();

    42     

    43     /**

    44      * Defines the name of the default component.

    45      * @return a String with the name of the default component.

    46      */

    47     protected String getDefaultComponentName() {

    48         return DEFAULT_COMPONENT;

    49     }

    50     

    51     /**

    52      * Get the default component instance from the database.

    53      * Or create it if needed.

    54      * @param logFile logFile to associate the component to.

    55      * @return the Component instance. 

    56      */

    57     protected Component getDefaultComponent(LogFile logFile) {

    58         if (defaultComponent == null) {

    59             defaultComponent = getComponent(getDefaultComponentName(), logFile);

    60         }

    61         return defaultComponent;

    62     }

    63 

    64     /**

    65      * Get the database instance for the name component.

    66      * @param name the name of the component

    67      * @param logFile logFile to associate the component to.

    68      * @return the Component instance.

    69      */

    70     protected Component getComponent(String name, LogFile logFile) {

    71         if (!components.containsKey(name)) {

    72             Component component = createComponent(name, logFile);

    73             components.put(name, component);

    74             return component;

    75         }

    76         return components.get(name);

    77     }

    78     

    79     /**

    80      * Creates a new component. This method is called by the 

    81      * getComponent method if the component entity is not found

    82      * in the cache.

    83      * @param name the name of the component

    84      * @param logFile logFile to associate the component to.

    85      * @return the Component instance.

    86      */

    87     protected Component createComponent(String name, LogFile logFile) {

    88         Component component = new Component();

    89         component.setComponent(name);

    90         component.setLogFile(logFile);

    91         getEntityManager().getTransaction().begin();

    92         getEntityManager().persist(component);

    93         getEntityManager().getTransaction().commit();

    94         return component;

    95     }

    96 

    97     /**

    98      * Clear the components cache.

    99      */

   100     protected void clear() {

   101         components = new Hashtable<String, Component>();

   102         defaultComponent = null;

   103     }

   104 }