com.servicerocket.confluence.randombits.storage.EmptyStorage Maven / Gradle / Ivy
/*
* Copyright (c) 2006, David Peterson
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of "randombits.org" nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
package com.servicerocket.confluence.randombits.storage;
import java.util.Collections;
import java.util.Set;
/**
* This storage implementation will act like it is storing, but will never actually
* store any data. This is useful in situations where a storage instance is expected but no
* actual storing is done and it's simpler than adding != null tests everywhere.
*
* @author David Peterson
*/
public class EmptyStorage extends ObjectBasedStorage
{
private boolean isReadOnly;
/**
* Constructs a new empty storage location which will never
* store any data entered into it.
*/
public EmptyStorage()
{
this(false);
}
/**
* @param isReadOnly Sets whether this storage will report itself as
* read-only.
*/
public EmptyStorage(boolean isReadOnly)
{
super(BoxType.Virtual);
this.isReadOnly = isReadOnly;
}
/**
* @return an empty set.
*/
@Override protected Set baseNameSet()
{
return Collections.EMPTY_SET;
}
/**
* Returns an object stored with the specified name.
*
* @param name The name of the value to return.
* @return the stored object.
*/
@Override protected Object getBaseObject(String name)
{
return null;
}
/**
* Sets the object in the base object.
*
* @param name The name of the value.
* @param value The object value to set.
*/
@Override protected void setBaseObject(String name, Object value)
{
// Do nothing...
}
/**
* @see Storage#isReadOnly()
*/
@Override public boolean isReadOnly()
{
return isReadOnly;
}
}