org.broadleafcommerce.common.extensibility.context.merge.DynamicResourceIterator.java Source code

Introduction

Here is the source code for org.broadleafcommerce.common.extensibility.context.merge.DynamicResourceIterator.java

Source

/*
 * #%L
 * BroadleafCommerce Common Libraries
 * %%
 * Copyright (C) 2009 - 2013 Broadleaf Commerce
 * %%
 * 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.
 * #L%
 */
package org.broadleafcommerce.common.extensibility.context.merge;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.broadleafcommerce.common.extensibility.context.ResourceInputStream;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Collection;

/**
 * This class serves as a basic iterator for a list of source files to be
 * merged. The interesting part, however, is that additional resources
 * may be inserted at any time at the current iterator position.
 *
 * @author Jeff Fischer
 */
public class DynamicResourceIterator extends ArrayList<ResourceInputStream> {

    private static final Log LOG = LogFactory.getLog(DynamicResourceIterator.class);

    private int position = 0;
    private int embeddedInsertPosition = 0;

    public ResourceInputStream nextResource() {
        ResourceInputStream ris = get(position);
        position++;
        embeddedInsertPosition = position;
        return ris;
    }

    public int getPosition() {
        return position;
    }

    public void addEmbeddedResource(ResourceInputStream ris) {
        if (embeddedInsertPosition == size()) {
            add(ris);
        } else {
            add(embeddedInsertPosition, ris);
        }
        embeddedInsertPosition++;
    }

    public boolean hasNext() {
        return position < size();
    }

    @Override
    public boolean add(ResourceInputStream resourceInputStream) {
        byte[] sourceArray;
        try {
            sourceArray = buildArrayFromStream(resourceInputStream);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        ResourceInputStream ris = new ResourceInputStream(new ByteArrayInputStream(sourceArray), null,
                resourceInputStream.getNames());
        return super.add(ris);
    }

    @Override
    public boolean addAll(Collection<? extends ResourceInputStream> c) {
        for (ResourceInputStream ris : c) {
            if (!add(ris)) {
                return false;
            }
        }
        return true;
    }

    @Override
    public void add(int index, ResourceInputStream resourceInputStream) {
        byte[] sourceArray;
        try {
            sourceArray = buildArrayFromStream(resourceInputStream);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        ResourceInputStream ris = new ResourceInputStream(new ByteArrayInputStream(sourceArray), null,
                resourceInputStream.getNames());
        super.add(index, ris);
    }

    protected byte[] buildArrayFromStream(InputStream source) throws IOException {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        boolean eof = false;
        try {
            while (!eof) {
                int temp = source.read();
                if (temp == -1) {
                    eof = true;
                } else {
                    baos.write(temp);
                }
            }
        } finally {
            try {
                source.close();
            } catch (Throwable e) {
                LOG.error("Unable to merge source and patch locations", e);
            }
        }

        return baos.toByteArray();
    }
}