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.solr.handler.admin; import java.io.BufferedReader; import java.io.DataInputStream; import java.io.File; import java.io.StringWriter; import java.lang.management.ManagementFactory; import java.lang.management.OperatingSystemMXBean; import java.lang.management.RuntimeMXBean; import java.lang.reflect.Method; import java.net.InetAddress; import java.text.DecimalFormat; import java.util.Date; import java.util.Locale; import org.apache.commons.io.IOUtils; import org.apache.lucene.LucenePackage; import org.apache.solr.common.util.NamedList; import org.apache.solr.common.util.SimpleOrderedMap; import org.apache.solr.common.util.XML; import org.apache.solr.core.SolrCore; import org.apache.solr.handler.RequestHandlerBase; import org.apache.solr.request.SolrQueryRequest; import org.apache.solr.response.SolrQueryResponse; import org.apache.solr.schema.IndexSchema; import org.apache.solr.update.UpdateHandler; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * This handler returns system info * * NOTE: the response format is still likely to change. It should be designed so * that it works nicely with an XSLT transformation. Until we have a nice * XSLT front end for /admin, the format is still open to change. * * @version $Id: SystemInfoHandler.java 1067172 2011-02-04 12:50:14Z uschindler $ * @since solr 1.2 */ public class SystemInfoHandler extends RequestHandlerBase { private static Logger log = LoggerFactory.getLogger(SystemInfoHandler.class); @Override public void handleRequestBody(SolrQueryRequest req, SolrQueryResponse rsp) throws Exception { rsp.add("core", getCoreInfo(req.getCore())); rsp.add("lucene", getLuceneInfo()); rsp.add("jvm", getJvmInfo()); rsp.add("system", getSystemInfo()); rsp.setHttpCaching(false); } /** * Get system info */ private static SimpleOrderedMap<Object> getCoreInfo(SolrCore core) throws Exception { SimpleOrderedMap<Object> info = new SimpleOrderedMap<Object>(); IndexSchema schema = core.getSchema(); info.add("schema", schema != null ? schema.getSchemaName() : "no schema!"); // Host InetAddress addr = InetAddress.getLocalHost(); info.add("host", addr.getCanonicalHostName()); // Now info.add("now", new Date()); // Start Time info.add("start", new Date(core.getStartTime())); // Solr Home SimpleOrderedMap<Object> dirs = new SimpleOrderedMap<Object>(); dirs.add("instance", new File(core.getResourceLoader().getInstanceDir()).getAbsolutePath()); dirs.add("data", new File(core.getDataDir()).getAbsolutePath()); // dirs.add( "index", new File( core.getIndexDir(UpdateHandler.UPDATEPARTION) ).getAbsolutePath() ); info.add("directory", dirs); return info; } /** * Get system info */ public static SimpleOrderedMap<Object> getSystemInfo() throws Exception { SimpleOrderedMap<Object> info = new SimpleOrderedMap<Object>(); OperatingSystemMXBean os = ManagementFactory.getOperatingSystemMXBean(); info.add("name", os.getName()); info.add("version", os.getVersion()); info.add("arch", os.getArch()); // Java 1.6 addGetterIfAvaliable(os, "systemLoadAverage", info); // com.sun.management.UnixOperatingSystemMXBean addGetterIfAvaliable(os, "openFileDescriptorCount", info); addGetterIfAvaliable(os, "maxFileDescriptorCount", info); // com.sun.management.OperatingSystemMXBean addGetterIfAvaliable(os, "committedVirtualMemorySize", info); addGetterIfAvaliable(os, "totalPhysicalMemorySize", info); addGetterIfAvaliable(os, "totalSwapSpaceSize", info); addGetterIfAvaliable(os, "processCpuTime", info); try { if (!os.getName().toLowerCase(Locale.ENGLISH).startsWith("windows")) { // Try some command line things info.add("uname", execute("uname -a")); info.add("ulimit", execute("ulimit -n")); info.add("uptime", execute("uptime")); } } catch (Throwable ex) { } // ignore return info; } /** * Try to run a getter function. This is useful because java 1.6 has a few extra * useful functions on the <code>OperatingSystemMXBean</code> * * If you are running a sun jvm, there are nice functions in: * UnixOperatingSystemMXBean and com.sun.management.OperatingSystemMXBean * * it is package protected so it can be tested... */ static void addGetterIfAvaliable(Object obj, String getter, NamedList<Object> info) { // This is a 1.6 function, so lets do a little magic to *try* to make it work try { String n = Character.toUpperCase(getter.charAt(0)) + getter.substring(1); Method m = obj.getClass().getMethod("get" + n); Object v = m.invoke(obj, (Object[]) null); if (v != null) { info.add(getter, v); } } catch (Exception ex) { } // don't worry, this only works for 1.6 } /** * Utility function to execute a function */ private static String execute(String cmd) { DataInputStream in = null; BufferedReader reader = null; try { Process process = Runtime.getRuntime().exec(cmd); in = new DataInputStream(process.getInputStream()); // use default charset from locale here, because the command invoked also uses the default locale: return IOUtils.toString(in); } catch (Exception ex) { // ignore - log.warn("Error executing command", ex); return "(error executing: " + cmd + ")"; } finally { IOUtils.closeQuietly(reader); IOUtils.closeQuietly(in); } } /** * Get JVM Info - including memory info */ public static SimpleOrderedMap<Object> getJvmInfo() { SimpleOrderedMap<Object> jvm = new SimpleOrderedMap<Object>(); jvm.add("version", System.getProperty("java.vm.version")); jvm.add("name", System.getProperty("java.vm.name")); Runtime runtime = Runtime.getRuntime(); jvm.add("processors", runtime.availableProcessors()); long used = runtime.totalMemory() - runtime.freeMemory(); // not thread safe, but could be thread local DecimalFormat df = new DecimalFormat("#.#"); double percentUsed = ((double) (used) / (double) runtime.maxMemory()) * 100; SimpleOrderedMap<Object> mem = new SimpleOrderedMap<Object>(); mem.add("free", humanReadableUnits(runtime.freeMemory(), df)); mem.add("total", humanReadableUnits(runtime.totalMemory(), df)); mem.add("max", humanReadableUnits(runtime.maxMemory(), df)); mem.add("used", humanReadableUnits(used, df) + " (%" + df.format(percentUsed) + ")"); jvm.add("memory", mem); // JMX properties -- probably should be moved to a different handler SimpleOrderedMap<Object> jmx = new SimpleOrderedMap<Object>(); try { RuntimeMXBean mx = ManagementFactory.getRuntimeMXBean(); jmx.add("bootclasspath", mx.getBootClassPath()); jmx.add("classpath", mx.getClassPath()); // the input arguments passed to the Java virtual machine // which does not include the arguments to the main method. jmx.add("commandLineArgs", mx.getInputArguments()); // a map of names and values of all system properties. //jmx.add( "SYSTEM PROPERTIES", mx.getSystemProperties()); jmx.add("startTime", new Date(mx.getStartTime())); jmx.add("upTimeMS", mx.getUptime()); } catch (Exception e) { log.warn("Error getting JMX properties", e); } jvm.add("jmx", jmx); return jvm; } private static SimpleOrderedMap<Object> getLuceneInfo() throws Exception { SimpleOrderedMap<Object> info = new SimpleOrderedMap<Object>(); String solrImplVersion = ""; String solrSpecVersion = ""; String luceneImplVersion = ""; String luceneSpecVersion = ""; // --- Package p = SolrCore.class.getPackage(); StringWriter tmp = new StringWriter(); solrImplVersion = p.getImplementationVersion(); if (null != solrImplVersion) { XML.escapeCharData(solrImplVersion, tmp); solrImplVersion = tmp.toString(); } tmp = new StringWriter(); solrSpecVersion = p.getSpecificationVersion(); if (null != solrSpecVersion) { XML.escapeCharData(solrSpecVersion, tmp); solrSpecVersion = tmp.toString(); } p = LucenePackage.class.getPackage(); tmp = new StringWriter(); luceneImplVersion = p.getImplementationVersion(); if (null != luceneImplVersion) { XML.escapeCharData(luceneImplVersion, tmp); luceneImplVersion = tmp.toString(); } tmp = new StringWriter(); luceneSpecVersion = p.getSpecificationVersion(); if (null != luceneSpecVersion) { XML.escapeCharData(luceneSpecVersion, tmp); luceneSpecVersion = tmp.toString(); } // Add it to the list info.add("solr-spec-version", solrSpecVersion); info.add("solr-impl-version", solrImplVersion); info.add("lucene-spec-version", luceneSpecVersion); info.add("lucene-impl-version", luceneImplVersion); return info; } //////////////////////// SolrInfoMBeans methods ////////////////////// @Override public String getDescription() { return "Get System Info"; } @Override public String getVersion() { return "$Revision: 1067172 $"; } @Override public String getSourceId() { return "$Id: SystemInfoHandler.java 1067172 2011-02-04 12:50:14Z uschindler $"; } @Override public String getSource() { return "$URL: https://svn.apache.org/repos/asf/lucene/dev/branches/lucene_solr_3_5/solr/core/src/java/org/apache/solr/handler/admin/SystemInfoHandler.java $"; } private static final long ONE_KB = 1024; private static final long ONE_MB = ONE_KB * ONE_KB; private static final long ONE_GB = ONE_KB * ONE_MB; /** * Return good default units based on byte size. */ private static String humanReadableUnits(long bytes, DecimalFormat df) { String newSizeAndUnits; if (bytes / ONE_GB > 0) { newSizeAndUnits = String.valueOf(df.format((float) bytes / ONE_GB)) + " GB"; } else if (bytes / ONE_MB > 0) { newSizeAndUnits = String.valueOf(df.format((float) bytes / ONE_MB)) + " MB"; } else if (bytes / ONE_KB > 0) { newSizeAndUnits = String.valueOf(df.format((float) bytes / ONE_KB)) + " KB"; } else { newSizeAndUnits = String.valueOf(bytes) + " bytes"; } return newSizeAndUnits; } public NamedList getStatistics() { NamedList lst = super.getStatistics(); Info info = LinuxOsInfo.getInfo(); lst.add("higoInfo", info); return lst; } }