// This Source Code is in the Public Domain per: http://litesoft.org/License.txt
package org.litesoft.core;

import java.io.*;
import java.util.*;

import org.litesoft.core.typeutils.*;
import org.litesoft.core.util.*;

@SuppressWarnings({"UnusedDeclaration"})
public class ServerStore implements Disposable
{
    private Map mEntries = new HashMap();

    public ServerStore()
    {
    }

    public ServerStore( ServerStore pCopyFrom )
    {
        if ( pCopyFrom != null )
        {
            pCopyFrom.copyTo( mEntries );
        }
    }

    /**
     * Returns the object bound with the specified pClass Name in this ServerStore, or
     * <code>null</code> if no object is bound under the pClass Name.
     *
     * @param pClass specifying the Class Name of the object
     *
     * @return the object bound with the specified Class Name
     *
     * @throws IllegalArgumentException if pClass is null
     */
    @SuppressWarnings({"unchecked"})
    public synchronized final <T> T get( Class<T> pClass )
    {
        return (T) mEntries.get( pClass );
    }

    /**
     * Returns the object bound with the specified Class Name in this ServerStore, or
     * <code>null</code> if no object is bound under the Class Name.
     *
     * @param pClass specifying the Class Name of the object
     *
     * @return the object bound with the specified Class Name
     *
     * @throws IllegalArgumentException if pClass is null
     * @throws NoSuchElementException   if there is no object bound to the specified Class Name
     */
    public <T extends Serializable> T getRequired( Class<T> pClass )
            throws NoSuchElementException
    {
        T zInstance = get( pClass );
        if ( zInstance == null )
        {
            throw new NoSuchElementException();
        }
        return zInstance;
    }

    /**
     * Binds an object to this ServerStore, using the pClass Name specified.
     * If an object of the same pClass Name is already bound to this ServerStore,
     * the object is replaced.
     * <p/>
     * <p>If the value passed in is null, this has the same effect as calling
     * <code>removeAttribute()<code>.
     *
     * @param pClass    the Class Name to which the object will be bound;
     *                  cannot be null
     * @param pInstance the object to be bound
     *
     * @throws IllegalArgumentException if pClass is null
     */
    public final <T, V extends T> void set( Class<T> pClass, V pInstance )
    {
        if ( pInstance == null )
        {
            remove( pClass );
        }
        else
        {
            Object zPrev = LLput( assertNotNull( pClass ), pInstance );
            if ( pInstance != zPrev ) // Same Object!
            {
                LLdispose( zPrev );
            }
        }
    }

    /**
     * Removes the object bound with the specified pClass Name from
     * this ServerStore. If the ServerStore does not have an object
     * bound with the specified pClass Name, this method does nothing.
     *
     * @param pClass specifying the Class Name of the object
     *               to remove from this ServerStore
     *
     * @throws IllegalArgumentException if pClass is null
     */
    public final <T> void remove( Class<T> pClass )
    {
        LLdispose( LLremove( assertNotNull( pClass ) ) );
    }

    @Override
    protected void finalize()
            throws Throwable
    {
        dispose();
        super.finalize();
    }

    @Override
    public void dispose()
    {
        Map zMap;
        synchronized ( this )
        {
            zMap = mEntries;
            mEntries = null;
        }
        if ( zMap != null )
        {
            for ( Object zInstance : zMap.values() )
            {
                LLdispose( zInstance );
            }
        }
    }

    private <T> Class<T> assertNotNull( Class<T> pClass )
    {
        Objects.assertNotNull( "Class", pClass );
        return pClass;
    }

    @SuppressWarnings({"unchecked"})
    private synchronized <T, V extends T> Object LLput( Class<T> pClass, V pInstance )
    {
        return mEntries.put( pClass, pInstance );
    }

    private synchronized <T> Object LLremove( Class<T> pClass )
    {
        return mEntries.remove( pClass );
    }

    private void LLdispose( Object pInstance )
    {
        if ( pInstance instanceof Disposable )
        {
            ((Disposable) pInstance).dispose();
        }
    }

    @SuppressWarnings({"unchecked"})
    private synchronized void copyTo( Map pTarget )
    {
        pTarget.putAll( mEntries );
    }
}