Java tutorial
/* * Licensed to Metamarkets Group Inc. (Metamarkets) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. Metamarkets 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 io.druid.segment.data; import com.google.common.io.ByteSink; import com.google.common.io.ByteStreams; import com.google.common.io.CountingOutputStream; import com.google.common.primitives.Doubles; import com.google.common.primitives.Ints; import io.druid.java.util.common.io.smoosh.FileSmoosher; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.nio.ByteBuffer; import java.nio.ByteOrder; import java.nio.channels.Channels; import java.nio.channels.WritableByteChannel; public class EntireLayoutDoubleSupplierSerializer implements DoubleSupplierSerializer { private final IOPeon ioPeon; private final String valueFile; private final String metaFile; private CountingOutputStream valuesOut; private long metaCount = 0; private final ByteBuffer orderBuffer; private int numInserted = 0; public EntireLayoutDoubleSupplierSerializer(IOPeon ioPeon, String filenameBase, ByteOrder order) { this.ioPeon = ioPeon; this.valueFile = filenameBase + ".value"; this.metaFile = filenameBase + ".format"; this.orderBuffer = ByteBuffer.allocate(Doubles.BYTES); orderBuffer.order(order); } @Override public void open() throws IOException { valuesOut = new CountingOutputStream(ioPeon.makeOutputStream(valueFile)); } @Override public int size() { return numInserted; } @Override public void add(double value) throws IOException { orderBuffer.rewind(); orderBuffer.putDouble(value); valuesOut.write(orderBuffer.array()); ++numInserted; } @Override public void closeAndConsolidate(ByteSink consolidatedOut) throws IOException { close(); try (OutputStream out = consolidatedOut.openStream(); InputStream meta = ioPeon.makeInputStream(metaFile); InputStream value = ioPeon.makeInputStream(valueFile)) { ByteStreams.copy(meta, out); ByteStreams.copy(value, out); } } @Override public long getSerializedSize() { return metaCount + valuesOut.getCount(); } @Override public void writeToChannel(WritableByteChannel channel, FileSmoosher smoosher) throws IOException { try (InputStream meta = ioPeon.makeInputStream(metaFile); InputStream value = ioPeon.makeInputStream(valueFile)) { ByteStreams.copy(Channels.newChannel(meta), channel); ByteStreams.copy(Channels.newChannel(value), channel); } } @Override public void close() throws IOException { valuesOut.close(); try (CountingOutputStream metaOut = new CountingOutputStream(ioPeon.makeOutputStream(metaFile))) { metaOut.write(CompressedDoublesIndexedSupplier.version); metaOut.write(Ints.toByteArray(numInserted)); metaOut.write(Ints.toByteArray(0)); metaOut.write(CompressedObjectStrategy.CompressionStrategy.NONE.getId()); metaOut.close(); metaCount = metaOut.getCount(); } } }