| /* |
| * 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.cassandra.db.tries; |
| |
| import java.util.function.Function; |
| |
| import org.agrona.DirectBuffer; |
| |
| /** |
| * A class for dumping the structure of a trie to a graphviz/dot representation for making trie graphs. |
| */ |
| class TrieToMermaid<T> extends TriePathReconstructor implements Trie.Walker<T, String> |
| { |
| private final StringBuilder b; |
| private final Function<T, String> contentToString; |
| private final Function<Integer, String> transitionToString; |
| private final boolean useMultiByte; |
| private int prevPos; |
| private int currNodeTextPos; |
| |
| public TrieToMermaid(Function<T, String> contentToString, |
| Function<Integer, String> transitionToString, |
| boolean useMultiByte) |
| { |
| this.contentToString = contentToString; |
| this.transitionToString = transitionToString; |
| this.useMultiByte = useMultiByte; |
| this.b = new StringBuilder(); |
| b.append("graph TD"); |
| newLineAndIndent(); |
| addNodeDefinition(nodeString(0)); |
| newLineAndIndent(); |
| b.append("style " + nodeString(0) + " fill:darkgrey"); |
| } |
| |
| @Override |
| public void resetPathLength(int newLength) |
| { |
| super.resetPathLength(newLength); |
| prevPos = newLength; |
| } |
| |
| private void newLineAndIndent() |
| { |
| b.append('\n'); |
| for (int i = 0; i < prevPos + 1; ++i) |
| b.append(" "); |
| } |
| |
| @Override |
| public void addPathByte(int nextByte) |
| { |
| newLineAndIndent(); |
| super.addPathByte(nextByte); |
| b.append(nodeString(prevPos)); |
| String newNode = nodeString(keyPos); |
| b.append(" --\""); |
| for (int i = prevPos; i < keyPos - 1; ++i) |
| b.append(transitionToString.apply(keyBytes[i] & 0xFF)); |
| b.append(transitionToString.apply(nextByte)); |
| b.append("\"--> "); |
| addNodeDefinition(newNode); |
| } |
| |
| private void addNodeDefinition(String newNode) |
| { |
| prevPos = keyPos; |
| currNodeTextPos = b.length(); |
| b.append(String.format("%s(( ))", newNode)); |
| } |
| |
| private String nodeString(int keyPos) |
| { |
| StringBuilder b = new StringBuilder(); |
| b.append("Node_"); |
| for (int i = 0; i < keyPos; ++i) |
| b.append(transitionToString.apply(keyBytes[i] & 0xFF)); |
| return b.toString(); |
| } |
| |
| @Override |
| public void addPathBytes(DirectBuffer buffer, int pos, int count) |
| { |
| if (useMultiByte) |
| { |
| super.addPathBytes(buffer, pos, count); |
| } |
| else |
| { |
| for (int i = 0; i < count; ++i) |
| addPathByte(buffer.getByte(pos + i) & 0xFF); |
| } |
| } |
| |
| @Override |
| public void content(T content) |
| { |
| b.replace(currNodeTextPos, b.length(), String.format("%s(((%s)))", nodeString(keyPos), contentToString.apply(content))); |
| } |
| |
| @Override |
| public String complete() |
| { |
| b.append("\n"); |
| return b.toString(); |
| } |
| } |