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.apache.htrace.viewer; import com.google.protobuf.Message; import com.google.protobuf.Descriptors.FieldDescriptor; import java.io.InputStream; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.OutputStream; import java.io.OutputStreamWriter; import java.nio.charset.Charset; import java.util.ArrayList; import java.util.Iterator; import java.util.List; import java.util.Map; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.hbase.Cell; import org.apache.hadoop.hbase.CellUtil; import org.apache.hadoop.hbase.HBaseConfiguration; import org.apache.hadoop.hbase.client.Get; import org.apache.hadoop.hbase.client.HConnection; import org.apache.hadoop.hbase.client.HConnectionManager; import org.apache.hadoop.hbase.client.HTableInterface; import org.apache.hadoop.hbase.client.Result; import org.apache.hadoop.hbase.client.ResultScanner; import org.apache.hadoop.hbase.client.Scan; import org.apache.hadoop.hbase.util.Bytes; import org.apache.htrace.impl.HBaseSpanReceiver; import org.apache.htrace.protobuf.generated.SpanProtos; public class HBaseSpanViewer { private static final Log LOG = LogFactory.getLog(HBaseSpanViewer.class); private Configuration conf; private HConnection hconnection; private HTableInterface htable; private byte[] table; private byte[] cf; private byte[] icf; public HBaseSpanViewer(Configuration conf) { this.conf = conf; this.table = Bytes.toBytes(conf.get(HBaseSpanReceiver.TABLE_KEY, HBaseSpanReceiver.DEFAULT_TABLE)); this.cf = Bytes .toBytes(conf.get(HBaseSpanReceiver.COLUMNFAMILY_KEY, HBaseSpanReceiver.DEFAULT_COLUMNFAMILY)); this.icf = Bytes .toBytes(conf.get(HBaseSpanReceiver.INDEXFAMILY_KEY, HBaseSpanReceiver.DEFAULT_INDEXFAMILY)); } public void close() { stopClient(); } public void startClient() { if (this.htable == null) { try { this.hconnection = HConnectionManager.createConnection(conf); this.htable = hconnection.getTable(table); } catch (IOException e) { LOG.warn("Failed to create HBase connection. " + e.getMessage()); } } } public void stopClient() { try { if (this.htable != null) { this.htable.close(); this.htable = null; } if (this.hconnection != null) { this.hconnection.close(); this.hconnection = null; } } catch (IOException e) { LOG.warn("Failed to close HBase connection. " + e.getMessage()); } } public List<SpanProtos.Span> getSpans(long traceid) throws IOException { startClient(); List<SpanProtos.Span> spans = new ArrayList<SpanProtos.Span>(); Get get = new Get(Bytes.toBytes(traceid)); get.addFamily(this.cf); try { for (Cell cell : htable.get(get).listCells()) { InputStream in = new ByteArrayInputStream(cell.getQualifierArray(), cell.getQualifierOffset(), cell.getQualifierLength()); spans.add(SpanProtos.Span.parseFrom(in)); } } catch (IOException e) { LOG.warn("Failed to get spans from HBase. " + e.getMessage()); stopClient(); } return spans; } public List<SpanProtos.Span> getRootSpans() throws IOException { startClient(); Scan scan = new Scan(); scan.addColumn(this.icf, HBaseSpanReceiver.INDEX_SPAN_QUAL); List<SpanProtos.Span> spans = new ArrayList<SpanProtos.Span>(); try { ResultScanner scanner = htable.getScanner(scan); Result result = null; while ((result = scanner.next()) != null) { for (Cell cell : result.listCells()) { InputStream in = new ByteArrayInputStream(cell.getValueArray(), cell.getValueOffset(), cell.getValueLength()); spans.add(SpanProtos.Span.parseFrom(in)); } } } catch (IOException e) { LOG.warn("Failed to get root spans from HBase. " + e.getMessage()); stopClient(); } return spans; } public static String toJsonString(final Message message) throws IOException { ByteArrayOutputStream out = new ByteArrayOutputStream(); OutputStreamWriter writer = new OutputStreamWriter(out, Charset.defaultCharset()); appendJsonString(message, writer); writer.flush(); out.flush(); return out.toString(); } public static void appendJsonString(final Message message, OutputStreamWriter writer) throws IOException { writer.append("{"); for (Iterator<Map.Entry<FieldDescriptor, Object>> iter = message.getAllFields().entrySet().iterator(); iter .hasNext();) { Map.Entry<FieldDescriptor, Object> field = iter.next(); appendFields(field.getKey(), field.getValue(), writer); if (iter.hasNext()) { writer.append(","); } } writer.append("}"); } private static void appendFields(FieldDescriptor fd, Object value, OutputStreamWriter writer) throws IOException { writer.append("\""); writer.append(fd.getName()); writer.append("\""); writer.append(":"); if (fd.isRepeated()) { writer.append("["); for (Iterator<?> it = ((List<?>) value).iterator(); it.hasNext();) { appendValue(fd, it.next(), writer); if (it.hasNext()) { writer.append(","); } } writer.append("]"); } else { appendValue(fd, value, writer); } } private static void appendValue(FieldDescriptor fd, Object value, OutputStreamWriter writer) throws IOException { switch (fd.getType()) { case INT64: // write int as string for handling in javascript case STRING: writer.append("\""); writer.append(value.toString()); writer.append("\""); break; case MESSAGE: appendJsonString((Message) value, writer); break; default: throw new IOException("unexpected field type."); } } /** * Run basic test. * @throws IOException */ public static void main(String[] args) throws IOException { HBaseSpanViewer viewer = new HBaseSpanViewer(HBaseConfiguration.create()); if (args.length == 0) { List<SpanProtos.Span> spans = viewer.getRootSpans(); for (SpanProtos.Span span : spans) { System.out.println(toJsonString(span)); } } else { List<SpanProtos.Span> spans = viewer.getSpans(Long.parseLong(args[0])); for (SpanProtos.Span span : spans) { System.out.println(toJsonString(span)); } } viewer.close(); } }