net.ontopia.infoset.content.InMemoryContentStore.java Source code

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Here is the source code for net.ontopia.infoset.content.InMemoryContentStore.java

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/*
 * #!
 * Ontopia Content Store
 * #-
 * Copyright (C) 2001 - 2013 The Ontopia Project
 * #-
 * 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 net.ontopia.infoset.content;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Map;
import net.ontopia.topicmaps.core.TopicMapIF;
import org.apache.commons.io.IOUtils;

/**
 * INTERNAL: Content store implementation that saves everything in memory.
 */
public class InMemoryContentStore implements ContentStoreIF {
    private static InMemoryContentStore store;

    private int nextKey;
    private Map<Integer, byte[]> content;

    // --- Static interface

    public static ContentStoreIF getInstance(TopicMapIF topicmap) {
        if (store == null)
            store = new InMemoryContentStore();
        return store;
    }

    // --- ContentStoreIF implementation

    public InMemoryContentStore() {
        content = new HashMap<Integer, byte[]>();
    }

    @Override
    public boolean containsKey(int key) throws ContentStoreException {
        return content.containsKey(new Integer(key));
    }

    @Override
    public ContentInputStream get(int key) throws ContentStoreException {
        byte[] data = content.get(new Integer(key));
        if (data == null)
            throw new ContentStoreException("No content for key " + key);
        return new ContentInputStream(new ByteArrayInputStream(data), data.length);
    }

    @Override
    public int add(ContentInputStream data) throws ContentStoreException {
        return add(data, data.getLength());
    }

    @Override
    public int add(InputStream data, int length) throws ContentStoreException {
        try {
            content.put(nextKey, IOUtils.toByteArray(data));
            return nextKey++;
        } catch (IOException e) {
            throw new ContentStoreException(e);
        }
    }

    @Override
    public boolean remove(int key) throws ContentStoreException {
        Integer okey = new Integer(key);
        boolean result = content.containsKey(okey);
        content.remove(okey);
        return result;
    }

    @Override
    public void close() throws ContentStoreException {
        content = null;
    }

}