001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase.io.hfile;
019
020import static org.apache.hbase.thirdparty.com.google.common.base.Preconditions.checkArgument;
021import static org.apache.hbase.thirdparty.com.google.common.base.Preconditions.checkNotNull;
022
023import java.io.IOException;
024import org.apache.hadoop.fs.FileSystem;
025import org.apache.hadoop.fs.Path;
026import org.apache.hadoop.hbase.fs.HFileSystem;
027import org.apache.hadoop.hbase.io.FSDataInputStreamWrapper;
028import org.apache.hadoop.hbase.io.hfile.ReaderContext.ReaderType;
029import org.apache.hadoop.hbase.keymeta.ManagedKeyDataCache;
030import org.apache.hadoop.hbase.keymeta.SystemKeyCache;
031import org.apache.yetus.audience.InterfaceAudience;
032
033/**
034 * A builder that helps in building up the ReaderContext
035 */
036@InterfaceAudience.Private
037public class ReaderContextBuilder {
038  private Path filePath;
039  private FSDataInputStreamWrapper fsdis;
040  private long fileSize;
041  private HFileSystem hfs;
042  private boolean primaryReplicaReader = true;
043  private ReaderType type = ReaderType.PREAD;
044  private SystemKeyCache systemKeyCache;
045  private ManagedKeyDataCache managedKeyDataCache;
046
047  public ReaderContextBuilder() {
048  }
049
050  public static ReaderContextBuilder newBuilder(ReaderContext readerContext) {
051    return new ReaderContextBuilder(readerContext);
052  }
053
054  private ReaderContextBuilder(ReaderContext readerContext) {
055    this.filePath = readerContext.getFilePath();
056    this.fsdis = readerContext.getInputStreamWrapper();
057    this.fileSize = readerContext.getFileSize();
058    this.hfs = readerContext.getFileSystem();
059    this.type = readerContext.getReaderType();
060    this.systemKeyCache = readerContext.getSystemKeyCache();
061    this.managedKeyDataCache = readerContext.getManagedKeyDataCache();
062  }
063
064  public ReaderContextBuilder withFilePath(Path filePath) {
065    this.filePath = filePath;
066    return this;
067  }
068
069  public ReaderContextBuilder withFileSize(long fileSize) {
070    this.fileSize = fileSize;
071    return this;
072  }
073
074  public ReaderContextBuilder withInputStreamWrapper(FSDataInputStreamWrapper fsdis) {
075    this.fsdis = fsdis;
076    return this;
077  }
078
079  public ReaderContextBuilder withFileSystem(HFileSystem hfs) {
080    this.hfs = hfs;
081    return this;
082  }
083
084  public ReaderContextBuilder withFileSystem(FileSystem fs) {
085    if (!(fs instanceof HFileSystem)) {
086      this.hfs = new HFileSystem(fs);
087    } else {
088      this.hfs = (HFileSystem) fs;
089    }
090    return this;
091  }
092
093  public ReaderContextBuilder withPrimaryReplicaReader(boolean primaryReplicaReader) {
094    this.primaryReplicaReader = primaryReplicaReader;
095    return this;
096  }
097
098  public ReaderContextBuilder withReaderType(ReaderType type) {
099    this.type = type;
100    return this;
101  }
102
103  public ReaderContextBuilder withFileSystemAndPath(FileSystem fs, Path filePath)
104    throws IOException {
105    this.withFileSystem(fs).withFilePath(filePath).withFileSize(fs.getFileStatus(filePath).getLen())
106      .withInputStreamWrapper(new FSDataInputStreamWrapper(fs, filePath));
107    return this;
108  }
109
110  public ReaderContextBuilder withManagedKeyDataCache(ManagedKeyDataCache managedKeyDataCache) {
111    this.managedKeyDataCache = managedKeyDataCache;
112    return this;
113  }
114
115  public ReaderContextBuilder withSystemKeyCache(SystemKeyCache systemKeyCache) {
116    this.systemKeyCache = systemKeyCache;
117    return this;
118  }
119
120  public ReaderContext build() {
121    validateFields();
122    return new ReaderContext(filePath, fsdis, fileSize, hfs, primaryReplicaReader, type,
123      systemKeyCache, managedKeyDataCache);
124  }
125
126  private void validateFields() throws IllegalArgumentException {
127    checkNotNull(filePath, "Illegal ReaderContext, no filePath specified.");
128    checkNotNull(fsdis, "Illegal ReaderContext, no StreamWrapper specified.");
129    checkNotNull(hfs, "Illegal ReaderContext, no HFileSystem specified.");
130    checkArgument(fileSize > 0L, "Illegal ReaderContext, fileSize <= 0");
131  }
132}