Java tutorial
/* * Licensed 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 com.addthis.hydra.data.tree.prop; import com.addthis.bundle.core.Bundle; import com.addthis.bundle.core.BundleField; import com.addthis.bundle.util.ValueUtil; import com.addthis.bundle.value.ValueFactory; import com.addthis.bundle.value.ValueObject; import com.addthis.codec.Codec; import com.addthis.hydra.data.tree.DataTreeNode; import com.addthis.hydra.data.tree.DataTreeNodeUpdater; import com.addthis.hydra.data.tree.TreeDataParameters; import com.addthis.hydra.data.tree.TreeNodeData; import com.addthis.basis.util.Varint; import io.netty.buffer.ByteBuf; import io.netty.buffer.PooledByteBufAllocator; import io.netty.buffer.Unpooled; public class DataTime extends TreeNodeData<DataTime.Config> { /** * This data attachment <span class="hydra-summary">stores the lowest and * highest values for a specified field</span>. * <p/> * <p>Job Configuration Example:</p> * <pre> * { type : "value", key : "ID", data : { * time : { type : "time", key : "TIME"}, * }},</pre> * * <p><b>Query Path Directives</b> * * <p>${attachment}=first returns the lowest value. * <p>${attachment}=last returns the highest value. * <p>${attachment}=life returns the highest value minus the lowest value. * * <p>% operations are not supported</p> * * <p>Query Path Example:</p> * <pre> * /+$+time=life * </pre> * * @user-reference * @hydra-name time */ public static final class Config extends TreeDataParameters<DataTime> { /** * Bundle field name from which to draw values. * This field is required. */ @Codec.Set(codable = true, required = true) private String key; @Override public DataTime newInstance() { return new DataTime(); } } @Codec.Set(codable = true) private long first = Long.MAX_VALUE; @Codec.Set(codable = true) private long last = Long.MIN_VALUE; private BundleField keyAccess; public long first() { return first; } public long last() { return last; } @Override public boolean updateChildData(DataTreeNodeUpdater state, DataTreeNode tn, Config conf) { Bundle p = state.getBundle(); if (keyAccess == null) { keyAccess = p.getFormat().getField(conf.key); } long packetTime = ValueUtil.asNumber(p.getValue(keyAccess)).asLong().getLong(); first = Math.min(first, packetTime); last = Math.max(last, packetTime); return true; } @Override public ValueObject getValue(String key) { if (key == null) { return null; } else if (key.equals("first")) { return ValueFactory.create(first); } else if (key.equals("last")) { return ValueFactory.create(last); } else if (key.equals("life")) { return ValueFactory.create(last - first); } else { return null; } } @Override public byte[] bytesEncode(long version) { byte[] encodedBytes = null; ByteBuf byteBuf = PooledByteBufAllocator.DEFAULT.buffer(); try { long delta = last - first; Varint.writeUnsignedVarLong(first, byteBuf); Varint.writeUnsignedVarLong(delta, byteBuf); encodedBytes = new byte[byteBuf.readableBytes()]; byteBuf.readBytes(encodedBytes); } finally { byteBuf.release(); } return encodedBytes; } @Override public void bytesDecode(byte[] b, long version) { ByteBuf byteBuf = Unpooled.wrappedBuffer(b); try { first = Varint.readUnsignedVarLong(byteBuf); last = first + Varint.readUnsignedVarLong(byteBuf); } finally { byteBuf.release(); } } public void setFirst(long first) { this.first = first; } public void setLast(long last) { this.last = last; } }