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.zeppelin.spark; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.PrintStream; import java.io.PrintWriter; import java.lang.reflect.Constructor; import java.lang.reflect.InvocationTargetException; import java.net.MalformedURLException; import java.net.URL; import java.net.URLClassLoader; import java.util.LinkedList; import java.util.List; import java.util.Map; import java.util.Properties; import com.google.common.reflect.TypeToken; import com.google.gson.Gson; import org.apache.commons.lang.StringUtils; import org.apache.spark.repl.SparkILoop; import org.apache.zeppelin.interpreter.Interpreter; import org.apache.zeppelin.interpreter.InterpreterContext; import org.apache.zeppelin.interpreter.InterpreterException; import org.apache.zeppelin.interpreter.InterpreterGroup; import org.apache.zeppelin.interpreter.InterpreterResult; import org.apache.zeppelin.interpreter.InterpreterResult.Code; import org.apache.zeppelin.interpreter.WrappedInterpreter; import org.apache.zeppelin.interpreter.thrift.InterpreterCompletion; import org.apache.zeppelin.scheduler.Scheduler; import org.apache.zeppelin.spark.dep.SparkDependencyContext; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.sonatype.aether.resolution.ArtifactResolutionException; import org.sonatype.aether.resolution.DependencyResolutionException; import scala.Console; import scala.None; import scala.Some; import scala.collection.convert.WrapAsJava$; import scala.collection.JavaConversions; import scala.tools.nsc.Settings; import scala.tools.nsc.interpreter.Completion.Candidates; import scala.tools.nsc.interpreter.Completion.ScalaCompleter; import scala.tools.nsc.interpreter.IMain; import scala.tools.nsc.interpreter.Results; import scala.tools.nsc.settings.MutableSettings.BooleanSetting; import scala.tools.nsc.settings.MutableSettings.PathSetting; /** * DepInterpreter downloads dependencies and pass them when SparkInterpreter initialized. * It extends SparkInterpreter but does not create sparkcontext * */ public class DepInterpreter extends Interpreter { /** * intp - org.apache.spark.repl.SparkIMain (scala 2.10) * intp - scala.tools.nsc.interpreter.IMain; (scala 2.11) */ private Object intp; private ByteArrayOutputStream out; private SparkDependencyContext depc; /** * completer - org.apache.spark.repl.SparkJLineCompletion (scala 2.10) */ private Object completer; private SparkILoop interpreter; static final Logger LOGGER = LoggerFactory.getLogger(DepInterpreter.class); public DepInterpreter(Properties property) { super(property); } public SparkDependencyContext getDependencyContext() { return depc; } public static String getSystemDefault(String envName, String propertyName, String defaultValue) { if (envName != null && !envName.isEmpty()) { String envValue = System.getenv().get(envName); if (envValue != null) { return envValue; } } if (propertyName != null && !propertyName.isEmpty()) { String propValue = System.getProperty(propertyName); if (propValue != null) { return propValue; } } return defaultValue; } @Override public void close() { if (intp != null) { Utils.invokeMethod(intp, "close"); } } @Override public void open() { out = new ByteArrayOutputStream(); createIMain(); } private void createIMain() { Settings settings = new Settings(); URL[] urls = getClassloaderUrls(); // set classpath for scala compiler PathSetting pathSettings = settings.classpath(); String classpath = ""; List<File> paths = currentClassPath(); for (File f : paths) { if (classpath.length() > 0) { classpath += File.pathSeparator; } classpath += f.getAbsolutePath(); } if (urls != null) { for (URL u : urls) { if (classpath.length() > 0) { classpath += File.pathSeparator; } classpath += u.getFile(); } } pathSettings.v_$eq(classpath); settings.scala$tools$nsc$settings$ScalaSettings$_setter_$classpath_$eq(pathSettings); // set classloader for scala compiler settings.explicitParentLoader_$eq(new Some<>(Thread.currentThread().getContextClassLoader())); BooleanSetting b = (BooleanSetting) settings.usejavacp(); b.v_$eq(true); settings.scala$tools$nsc$settings$StandardScalaSettings$_setter_$usejavacp_$eq(b); interpreter = new SparkILoop((java.io.BufferedReader) null, new PrintWriter(out)); interpreter.settings_$eq(settings); interpreter.createInterpreter(); intp = Utils.invokeMethod(interpreter, "intp"); if (Utils.isScala2_10()) { Utils.invokeMethod(intp, "setContextClassLoader"); Utils.invokeMethod(intp, "initializeSynchronous"); } depc = new SparkDependencyContext(getProperty("zeppelin.dep.localrepo"), getProperty("zeppelin.dep.additionalRemoteRepository")); if (Utils.isScala2_10()) { completer = Utils.instantiateClass("org.apache.spark.repl.SparkJLineCompletion", new Class[] { Utils.findClass("org.apache.spark.repl.SparkIMain") }, new Object[] { intp }); } interpret("@transient var _binder = new java.util.HashMap[String, Object]()"); Map<String, Object> binder; if (Utils.isScala2_10()) { binder = (Map<String, Object>) getValue("_binder"); } else { binder = (Map<String, Object>) getLastObject(); } binder.put("depc", depc); interpret("@transient val z = " + "_binder.get(\"depc\")" + ".asInstanceOf[org.apache.zeppelin.spark.dep.SparkDependencyContext]"); } private Results.Result interpret(String line) { return (Results.Result) Utils.invokeMethod(intp, "interpret", new Class[] { String.class }, new Object[] { line }); } public Object getValue(String name) { Object ret = Utils.invokeMethod(intp, "valueOfTerm", new Class[] { String.class }, new Object[] { name }); if (ret instanceof None) { return null; } else if (ret instanceof Some) { return ((Some) ret).get(); } else { return ret; } } public Object getLastObject() { IMain.Request r = (IMain.Request) Utils.invokeMethod(intp, "lastRequest"); Object obj = r.lineRep().call("$result", JavaConversions.asScalaBuffer(new LinkedList<>())); return obj; } @Override public InterpreterResult interpret(String st, InterpreterContext context) throws InterpreterException { PrintStream printStream = new PrintStream(out); Console.setOut(printStream); out.reset(); SparkInterpreter sparkInterpreter = getInterpreterInTheSameSessionByClassName(SparkInterpreter.class, false); if (sparkInterpreter != null && sparkInterpreter.getDelegation().isSparkContextInitialized()) { return new InterpreterResult(Code.ERROR, "Must be used before SparkInterpreter (%spark) initialized\n" + "Hint: put this paragraph before any Spark code and " + "restart Zeppelin/Interpreter"); } scala.tools.nsc.interpreter.Results.Result ret = interpret(st); Code code = getResultCode(ret); try { depc.fetch(); } catch (MalformedURLException | DependencyResolutionException | ArtifactResolutionException e) { LOGGER.error("Exception in DepInterpreter while interpret ", e); return new InterpreterResult(Code.ERROR, e.toString()); } if (code == Code.INCOMPLETE) { return new InterpreterResult(code, "Incomplete expression"); } else if (code == Code.ERROR) { return new InterpreterResult(code, out.toString()); } else { return new InterpreterResult(code, out.toString()); } } private Code getResultCode(scala.tools.nsc.interpreter.Results.Result r) { if (r instanceof scala.tools.nsc.interpreter.Results.Success$) { return Code.SUCCESS; } else if (r instanceof scala.tools.nsc.interpreter.Results.Incomplete$) { return Code.INCOMPLETE; } else { return Code.ERROR; } } @Override public void cancel(InterpreterContext context) { } @Override public FormType getFormType() { return FormType.NATIVE; } @Override public int getProgress(InterpreterContext context) { return 0; } @Override public List<InterpreterCompletion> completion(String buf, int cursor, InterpreterContext interpreterContext) { if (Utils.isScala2_10()) { ScalaCompleter c = (ScalaCompleter) Utils.invokeMethod(completer, "completer"); Candidates ret = c.complete(buf, cursor); List<String> candidates = WrapAsJava$.MODULE$.seqAsJavaList(ret.candidates()); List<InterpreterCompletion> completions = new LinkedList<>(); for (String candidate : candidates) { completions.add(new InterpreterCompletion(candidate, candidate, StringUtils.EMPTY)); } return completions; } else { return new LinkedList<>(); } } private List<File> currentClassPath() { List<File> paths = classPath(Thread.currentThread().getContextClassLoader()); String[] cps = System.getProperty("java.class.path").split(File.pathSeparator); if (cps != null) { for (String cp : cps) { paths.add(new File(cp)); } } return paths; } private List<File> classPath(ClassLoader cl) { List<File> paths = new LinkedList<>(); if (cl == null) { return paths; } if (cl instanceof URLClassLoader) { URLClassLoader ucl = (URLClassLoader) cl; URL[] urls = ucl.getURLs(); if (urls != null) { for (URL url : urls) { paths.add(new File(url.getFile())); } } } return paths; } @Override public Scheduler getScheduler() { try { SparkInterpreter sparkInterpreter = getInterpreterInTheSameSessionByClassName(SparkInterpreter.class, false); if (sparkInterpreter != null) { return sparkInterpreter.getScheduler(); } else { return null; } } catch (InterpreterException e) { return null; } } }