Java tutorial
/* * 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. */ package org.jclouds.blobstore; import static com.google.common.base.Preconditions.checkNotNull; import static com.google.common.io.BaseEncoding.base16; import static org.jclouds.http.Uris.uriBuilder; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.util.Date; import java.util.Map; import java.util.concurrent.ConcurrentHashMap; import java.util.concurrent.ConcurrentMap; import javax.inject.Inject; import javax.ws.rs.core.HttpHeaders; import org.jclouds.blobstore.domain.Blob; import org.jclouds.blobstore.domain.Blob.Factory; import org.jclouds.blobstore.options.ListContainerOptions; import org.jclouds.blobstore.util.BlobStoreUtils; import org.jclouds.date.DateService; import org.jclouds.domain.Location; import org.jclouds.http.HttpUtils; import org.jclouds.io.ContentMetadataCodec; import org.jclouds.io.MutableContentMetadata; import org.jclouds.io.Payload; import org.jclouds.io.Payloads; import org.jclouds.io.payloads.ByteArrayPayload; import org.jclouds.io.payloads.DelegatingPayload; import com.google.common.base.Supplier; import com.google.common.base.Throwables; import com.google.common.collect.ImmutableList; import com.google.common.collect.Multimaps; public class TransientStorageStrategy implements LocalStorageStrategy { private final ConcurrentMap<String, ConcurrentMap<String, Blob>> containerToBlobs = new ConcurrentHashMap<String, ConcurrentMap<String, Blob>>(); private final ConcurrentMap<String, Location> containerToLocation = new ConcurrentHashMap<String, Location>(); private final Supplier<Location> defaultLocation; private final DateService dateService; private final Factory blobFactory; private final ContentMetadataCodec contentMetadataCodec; @Inject TransientStorageStrategy(Supplier<Location> defaultLocation, DateService dateService, Factory blobFactory, ContentMetadataCodec contentMetadataCodec) { this.defaultLocation = defaultLocation; this.dateService = dateService; this.blobFactory = blobFactory; this.contentMetadataCodec = contentMetadataCodec; } @Override public boolean containerExists(final String containerName) { return containerToBlobs.containsKey(containerName); } @Override public Iterable<String> getAllContainerNames() { return containerToBlobs.keySet(); } @Override public boolean createContainerInLocation(final String containerName, final Location location) { ConcurrentMap<String, Blob> origValue = containerToBlobs.putIfAbsent(containerName, new ConcurrentHashMap<String, Blob>()); if (origValue != null) { return false; } containerToLocation.put(containerName, location != null ? location : defaultLocation.get()); return true; } @Override public void deleteContainer(final String containerName) { containerToBlobs.remove(containerName); } @Override public void clearContainer(final String containerName) { clearContainer(containerName, ListContainerOptions.Builder.recursive()); } @Override public void clearContainer(String containerName, ListContainerOptions options) { // TODO implement options containerToBlobs.get(containerName).clear(); } @Override public boolean blobExists(final String containerName, final String blobName) { Map<String, Blob> map = containerToBlobs.get(containerName); return map != null && map.containsKey(blobName); } @Override public Iterable<String> getBlobKeysInsideContainer(final String containerName) { return containerToBlobs.get(containerName).keySet(); } @Override public Blob getBlob(final String containerName, final String blobName) { Map<String, Blob> map = containerToBlobs.get(containerName); return map == null ? null : map.get(blobName); } @Override public String putBlob(final String containerName, final Blob blob) throws IOException { Blob newBlob = createUpdatedCopyOfBlobInContainer(containerName, blob); Map<String, Blob> map = containerToBlobs.get(containerName); map.put(newBlob.getMetadata().getName(), newBlob); Payloads.calculateMD5(newBlob); return base16().lowerCase().encode(newBlob.getPayload().getContentMetadata().getContentMD5()); } @Override public void removeBlob(final String containerName, final String blobName) { Map<String, Blob> map = containerToBlobs.get(containerName); if (map != null) map.remove(blobName); } @Override public Location getLocation(final String containerName) { return containerToLocation.get(containerName); } @Override public String getSeparator() { return "/"; } private Blob createUpdatedCopyOfBlobInContainer(String containerName, Blob in) { checkNotNull(in, "blob"); checkNotNull(in.getPayload(), "blob.payload"); ByteArrayPayload payload = (in.getPayload() instanceof ByteArrayPayload) ? ByteArrayPayload.class.cast(in.getPayload()) : null; if (payload == null) payload = (in.getPayload() instanceof DelegatingPayload) ? (DelegatingPayload.class.cast(in.getPayload()).getDelegate() instanceof ByteArrayPayload) ? ByteArrayPayload.class .cast(DelegatingPayload.class.cast(in.getPayload()).getDelegate()) : null : null; try { if (payload == null || !(payload instanceof ByteArrayPayload)) { MutableContentMetadata oldMd = in.getPayload().getContentMetadata(); ByteArrayOutputStream out = new ByteArrayOutputStream(); in.getPayload().writeTo(out); payload = (ByteArrayPayload) Payloads.calculateMD5(Payloads.newPayload(out.toByteArray())); HttpUtils.copy(oldMd, payload.getContentMetadata()); } else { if (payload.getContentMetadata().getContentMD5() == null) Payloads.calculateMD5(in); } } catch (IOException e) { Throwables.propagate(e); } Blob blob = blobFactory.create(BlobStoreUtils.copy(in.getMetadata())); blob.setPayload(payload); blob.getMetadata().setContainer(containerName); blob.getMetadata().setUri(uriBuilder(new StringBuilder("mem://").append(containerName)) .path(in.getMetadata().getName()).build()); blob.getMetadata().setLastModified(new Date()); String eTag = base16().lowerCase().encode(payload.getContentMetadata().getContentMD5()); blob.getMetadata().setETag(eTag); // Set HTTP headers to match metadata blob.getAllHeaders().replaceValues(HttpHeaders.LAST_MODIFIED, ImmutableList.of(dateService.rfc822DateFormat(blob.getMetadata().getLastModified()))); blob.getAllHeaders().replaceValues(HttpHeaders.ETAG, ImmutableList.of(eTag)); copyPayloadHeadersToBlob(payload, blob); blob.getAllHeaders().putAll(Multimaps.forMap(blob.getMetadata().getUserMetadata())); return blob; } private void copyPayloadHeadersToBlob(Payload payload, Blob blob) { blob.getAllHeaders().putAll(contentMetadataCodec.toHeaders(payload.getContentMetadata())); } }