HeapResourceFactory.java

/*
 * ====================================================================
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */
package com.apigee.sdk.apm.http.impl.client.cache;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;

import com.apigee.sdk.apm.http.annotation.Immutable;
import com.apigee.sdk.apm.http.client.cache.InputLimit;
import com.apigee.sdk.apm.http.client.cache.Resource;
import com.apigee.sdk.apm.http.client.cache.ResourceFactory;

/**
 * Generates {@link Resource} instances stored entirely in heap.
 * 
 * @since 4.1
 */
@Immutable
public class HeapResourceFactory implements ResourceFactory {

	public Resource generate(final String requestId,
			final InputStream instream, final InputLimit limit)
			throws IOException {
		ByteArrayOutputStream outstream = new ByteArrayOutputStream();
		byte[] buf = new byte[2048];
		long total = 0;
		int l;
		while ((l = instream.read(buf)) != -1) {
			// System.out.println("Current Size:" + total);
			outstream.write(buf, 0, l);
			total += l;
			if (limit != null && total > limit.getValue()) {
				limit.reached();
				break;
			}
		}
		return new HeapResource(outstream.toByteArray());
	}

	public Resource copy(final String requestId, final Resource resource)
			throws IOException {
		byte[] body;
		if (resource instanceof HeapResource) {
			body = ((HeapResource) resource).getByteArray();
		} else {
			ByteArrayOutputStream outstream = new ByteArrayOutputStream();
			IOUtils.copyAndClose(resource.getInputStream(), outstream);
			body = outstream.toByteArray();
		}
		return new HeapResource(body);
	}

}