| /* |
| * 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.apache.nifi.controller; |
| |
| import com.google.common.cache.Cache; |
| import com.google.common.cache.CacheBuilder; |
| import java.io.ByteArrayInputStream; |
| import java.io.ByteArrayOutputStream; |
| import java.io.DataInputStream; |
| import java.io.DataOutputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.util.ArrayList; |
| import java.util.Collection; |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.concurrent.TimeUnit; |
| import org.apache.nifi.persistence.StandardSnippetDeserializer; |
| import org.apache.nifi.persistence.StandardSnippetSerializer; |
| import org.apache.nifi.stream.io.StreamUtils; |
| |
| public class SnippetManager { |
| |
| private final Cache<String, StandardSnippet> snippetMap = CacheBuilder.newBuilder().expireAfterWrite(1, TimeUnit.MINUTES).build(); |
| |
| public synchronized void addSnippet(final StandardSnippet snippet) { |
| if (snippetMap.getIfPresent(snippet.getId()) != null) { |
| throw new IllegalStateException("Snippet with ID " + snippet.getId() + " already exists"); |
| } |
| snippetMap.put(snippet.getId(), snippet); |
| } |
| |
| public synchronized void removeSnippet(final StandardSnippet snippet) { |
| if (snippetMap.getIfPresent(snippet.getId()) == null) { |
| throw new IllegalStateException("Snippet is not contained in this SnippetManager"); |
| } |
| snippetMap.invalidate(snippet.getId()); |
| } |
| |
| public synchronized StandardSnippet getSnippet(final String identifier) { |
| return snippetMap.getIfPresent(identifier); |
| } |
| |
| public synchronized Collection<StandardSnippet> getSnippets() { |
| return Collections.unmodifiableCollection(snippetMap.asMap().values()); |
| } |
| |
| public synchronized void clear() { |
| snippetMap.invalidateAll(); |
| } |
| |
| public static List<StandardSnippet> parseBytes(final byte[] bytes) { |
| final List<StandardSnippet> snippets = new ArrayList<>(); |
| |
| try (final InputStream rawIn = new ByteArrayInputStream(bytes); |
| final DataInputStream in = new DataInputStream(rawIn)) { |
| final int length = in.readInt(); |
| final byte[] buffer = new byte[length]; |
| StreamUtils.fillBuffer(in, buffer, true); |
| final StandardSnippet snippet = StandardSnippetDeserializer.deserialize(new ByteArrayInputStream(buffer)); |
| snippets.add(snippet); |
| } catch (final IOException e) { |
| throw new RuntimeException("Failed to parse bytes", e); // should never happen because of streams being used |
| } |
| |
| return snippets; |
| } |
| |
| public byte[] export() { |
| try (final ByteArrayOutputStream baos = new ByteArrayOutputStream(); |
| final DataOutputStream dos = new DataOutputStream(baos)) { |
| for (final StandardSnippet snippet : getSnippets()) { |
| final byte[] bytes = StandardSnippetSerializer.serialize(snippet); |
| dos.writeInt(bytes.length); |
| dos.write(bytes); |
| } |
| |
| return baos.toByteArray(); |
| } catch (final IOException e) { |
| // won't happen |
| return null; |
| } |
| } |
| } |