com.opsmatters.core.provider.ResourceCache Maven / Gradle / Ivy
/*
* Copyright 2018 Gerald Curley
*
* Licensed 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
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* 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 com.opsmatters.core.provider;
import java.util.Collection;
/**
* Represents the base class for all provider resource caches.
*
* @author Gerald Curley (opsmatters)
*/
public abstract class ResourceCache
{
private String name = "";
private long updatedAt = 0L;
/**
* Constructor that takes a name.
* @param name The name of the items in the cache
*/
public ResourceCache(String name)
{
this.name = name;
}
/**
* Returns the name of the cache.
* @return The cache name
*/
public String getName()
{
return name;
}
/**
* Sets the date the cache was last updated.
* @param updatedAt The date the cache was last updated
*/
protected void setUpdatedAt(long updatedAt)
{
this.updatedAt = updatedAt;
}
/**
* Sets the date the cache was last updated to the current date.
*/
protected void setUpdatedAt()
{
setUpdatedAt(System.currentTimeMillis());
}
/**
* Returns the date the cache was last updated.
* @return The date the cache was last updated
*/
public long getUpdatedAt()
{
return updatedAt;
}
/**
* Returns a string representation of the object.
*/
@Override
public String toString()
{
return getName();
}
/**
* Adds an item to the cache.
* @param item The item to add
*/
public abstract void add(T item);
/**
* Adds the list to the items in the cache.
* @param items The items to add
*/
public abstract void add(Collection items);
/**
* Sets the cache to the items in the list.
* @param items The items to set
*/
public void set(Collection items)
{
clear();
add(items);
}
/**
* Returns the item for the given id.
* @param id The id of the item
* @return The item for the given id
*/
public abstract T get(long id);
/**
* Returns the items in the cache.
* @return The items in the cache
*/
public abstract Collection list();
/**
* Returns the size of the cache.
* @return The size of the cache
*/
public abstract int size();
/**
* Clears the cache.
*/
public abstract void clear();
}