Java tutorial
/** * Copyright 2014-2015 SHAF-WORK * * 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 org.shaf.server.log; import java.io.IOException; import java.io.RandomAccessFile; import java.util.Stack; import com.google.common.base.Strings; /** * The log-file writer in XES format. * * @author Mykola Galushka */ public class XesWriter extends FileWriter { /** * The opened tags stack. */ private Stack<String> tags; /** * The random access file for populating a log. */ private final RandomAccessFile raf; /** * Constructs a new log-file writer in XES format. * * @param path * the path to writing log file. * @param overwrite * the flag to overwrite log file. * @throws IOException * if the writer initialization error occurs. */ public XesWriter(final String path, final boolean overwrite) throws IOException { super(path, overwrite); this.tags = new Stack<>(); this.raf = new RandomAccessFile(path, "rw"); this.writeStartDocument(); this.writeStartElement("log", new String[][] { { "xes.version", "1.1" }, { "xes.features", "arbitrary-depth" }, { "xmlns", "http://www.xes-standard.org/" } }); this.writeStartElement("extension", new String[][] { { "name", "Concept" }, { "prefix", "concept" }, { "uri", "http://www.xes-standard.org/concept.xesext" } }); this.writeEndElement(); this.writeStartElement("extension", new String[][] { { "name", "Time" }, { "prefix", "time" }, { "uri", "http://www.xes-standard.org/time.xesext" } }); this.writeEndElement(); this.writeStartElement("global", new String[][] { { "scope", "trace" } }); this.writeStartElement("string", new String[][] { { "key", "concept:name" }, { "value", "Server Process Log" } }); this.writeEndElement(); this.writeEndElement(); this.writeEndDocument(); } /** * Constructs a new log-file writer in XES format. * * @param path * the path to writing log file. * @throws IOException * if the writer initialization error occurs. */ public XesWriter(final String path) throws IOException { this(path, true); } /** * Writes the start trace to XES log-file. */ @Override public void startTrace(final LogTrace trace) throws IOException { this.raf.seek(this.raf.length() - "</log>".length()); this.writeStartElement("trace"); this.writeStartElement("int", new String[][] { { "key", "concept:id" }, { "value", String.valueOf(trace.getId()) } }); this.writeEndElement(); this.writeStartElement("string", new String[][] { { "key", "concept:info" }, { "value", trace.getInfo() } }); this.writeEndElement(); } /** * Writes the start event to XES log-file. */ @Override public void startEvent(final LogEvent event) throws IOException { this.writeStartElement("event"); this.writeStartElement("string", new String[][] { { "key", "concept:name" }, { "value", event.getProcessName() } }); this.writeEndElement(); this.writeStartElement("string", new String[][] { { "key", "org:resource" }, { "value", event.getProcessResource() } }); this.writeEndElement(); this.writeStartElement("date", new String[][] { { "key", "time:timestamp" }, { "value", super.format(event.getTimestamp()) } }); this.writeEndElement(); this.writeStartElement("string", new String[][] { { "key", "concept:info" }, { "value", event.getInfo() } }); this.writeEndElement(); this.writeStartElement("string", new String[][] { { "key", "lifecycle:transition" }, { "value", "SCHEDULE" } }); this.writeEndElement(); this.writeEndElement(); } /** * Writes the end event to XES log-file. */ @Override public void endEvent(final LogEvent event) throws IOException { this.writeStartElement("event"); this.writeStartElement("string", new String[][] { { "key", "concept:name" }, { "value", event.getProcessName() } }); this.writeEndElement(); this.writeStartElement("string", new String[][] { { "key", "org:resource" }, { "value", event.getProcessResource() } }); this.writeEndElement(); this.writeStartElement("date", new String[][] { { "key", "time:timestamp" }, { "value", super.format(event.getTimestamp()) } }); this.writeEndElement(); this.writeStartElement("string", new String[][] { { "key", "lifecycle:transition" }, { "value", "COMPLETE" } }); this.writeEndElement(); this.writeEndElement(); } /** * Writes the end trace to XES log-file. */ public void endTrace(final LogTrace trace) throws IOException { this.writeEndElement(); this.writeEndDocument(); } /** * Closes the XES file writer. */ @Override public void close() throws IOException { if (this.raf != null) { this.raf.close(); } } // ======================================================================== // The service methods // ======================================================================== /** * Writes the start of the XES document. * * @throws IOException * if an I/O error occurs during writing process. */ private final void writeStartDocument() throws IOException { this.raf.writeBytes("<?xml version=\"1.0\" encoding=\"UTF-8\"?>" + System.lineSeparator()); } /** * Writes the start of the XES element. * * @param tag * the element tag name. * @param attributes * the element attributes. * @throws IOException * if an I/O error occurs during writing process. */ private final void writeStartElement(final String tag, final String[][] attributes) throws IOException { this.raf.writeBytes(Strings.repeat(" ", this.tags.size())); this.tags.push(tag); this.raf.writeBytes("<" + tag); if (attributes != null) { for (String[] attribute : attributes) { this.raf.writeBytes(" " + attribute[0] + "=\"" + attribute[1] + "\""); } } this.raf.writeBytes(">" + System.lineSeparator()); } /** * Writes the start of the XES element. * * @param tag * the element tag name. * @throws IOException * if an I/O error occurs during writing process. */ private final void writeStartElement(final String tag) throws IOException { this.writeStartElement(tag, null); } /** * Writes the end of the XES element. * * @param tag * the element tag name. * @throws IOException * if an I/O error occurs during writing process. */ private final void writeEndElement() throws IOException { String tag = this.tags.pop(); this.raf.writeBytes(Strings.repeat(" ", this.tags.size())); this.raf.writeBytes("</" + tag + ">" + System.lineSeparator()); } /** * Writes the end of the XES document. * * @throws IOException * if an I/O error occurs during writing process. */ private final void writeEndDocument() throws IOException { this.raf.writeBytes("</log>"); } }