/*
* 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.accumulo.core.trace;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import cloudtrace.instrument.Span;
import cloudtrace.thrift.RemoteSpan;
public class SpanTree {
final Map<Long,List<Long>> parentChildren = new HashMap<Long,List<Long>>();
public final Map<Long,RemoteSpan> nodes = new HashMap<Long,RemoteSpan>();
public SpanTree() {}
public void addNode(RemoteSpan span) {
nodes.put(span.spanId, span);
if (parentChildren.get(span.parentId) == null)
parentChildren.put(span.parentId, new ArrayList<Long>());
parentChildren.get(span.parentId).add(span.spanId);
}
public Set<Long> visit(SpanTreeVisitor visitor) {
Set<Long> visited = new HashSet<Long>();
List<Long> root = parentChildren.get(new Long(Span.ROOT_SPAN_ID));
if (root == null || root.isEmpty())
return visited;
RemoteSpan rootSpan = nodes.get(root.iterator().next());
if (rootSpan == null)
return visited;
recurse(0, null, rootSpan, visitor, visited);
return visited;
}
private void recurse(int level, RemoteSpan parent, RemoteSpan node, SpanTreeVisitor visitor, Set<Long> visited) {
// improbable case: duplicate spanId in a trace tree: prevent
// infinite recursion
if (visited.contains(node.spanId))
return;
visited.add(node.spanId);
List<RemoteSpan> children = new ArrayList<RemoteSpan>();
List<Long> childrenIds = parentChildren.get(node.spanId);
if (childrenIds != null) {
for (Long childId : childrenIds) {
RemoteSpan child = nodes.get(childId);
if (child != null) {
children.add(child);
}
}
}
children = TraceDump.sortByStart(children);
visitor.visit(level, parent, node, children);
for (RemoteSpan child : children) {
recurse(level + 1, node, child, visitor, visited);
}
}
}