ZEPPELIN-541 - increase logging in application

### What is this PR for?
To increase logging in the application, so as it

### What type of PR is it?
Refactoring

### Todos
* [x] - replace all printStackTrace() to LOGGER.error
* [x] - all catch block that doesn't throw exception, should have logging

### Is there a relevant Jira issue?
Yes, ZEPPELIN-541

### Screenshots (if appropriate)
N/A

Author: Prabhjyot Singh <prabhjyotsingh@gmail.com>

Closes #579 from prabhjyotsingh/increaseLogging and squashes the following commits:

ba053f5 [Prabhjyot Singh] revert note.json
648c65c [Prabhjyot Singh] fix CI
6d927fc [Prabhjyot Singh] Every catch should log error/info message or should throw an exception
7f8b70c [Prabhjyot Singh] replace printStackTrace() to LOGGER.error

ignite/src/main/java/org/apache/zeppelin/ignite/IgniteInterpreter.java

@@ -211,6 +211,7 @@ private Ignite getIgnite() {
 
         initEx = null;
       } catch (Exception e) {
+        logger.error("Error in IgniteInterpreter while getIgnite: " , e);
         initEx = e;
       }
     }

ignite/src/main/java/org/apache/zeppelin/ignite/IgniteSqlInterpreter.java

@@ -154,6 +154,7 @@ public InterpreterResult interpret(String st, InterpreterContext context) {
         }
       }
     } catch (Exception e) {
+      logger.error("Exception in IgniteSqlInterpreter while InterpreterResult interpret: ", e);
       return IgniteInterpreterUtils.buildErrorResult(e);
     } finally {
       curStmt = null;
@@ -169,6 +170,7 @@ public void cancel(InterpreterContext context) {
         curStmt.cancel();
       } catch (SQLException e) {
         // No-op.
+        logger.info("No-op while cancel in IgniteSqlInterpreter", e);
       } finally {
         curStmt = null;
       }

lens/src/main/java/org/apache/zeppelin/lens/LensInterpreter.java

@@ -128,7 +128,7 @@ public LensInterpreter(Properties property) {
       s_logger.info("LensInterpreter created");
     }
     catch (Exception e) {
-      e.printStackTrace();
+      s_logger.error(e.toString(), e);
       s_logger.error("unable to create lens interpreter", e);
     }
   }
@@ -375,6 +375,7 @@ public void cancel(InterpreterContext context) {
         closeShell(s_paraToQH.get(context.getParagraphId()).getShell());
       } catch (Exception e) {
         // ignore
+        s_logger.info("Exception in LensInterpreter while cancel finally, ignore", e);
       }
       s_paraToQH.remove(context.getParagraphId());
       closeShell(shell);

lens/src/main/java/org/apache/zeppelin/lens/LensJLineShellComponent.java

@@ -17,6 +17,9 @@
 
 import java.util.Map;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import org.springframework.beans.BeansException;
 import org.springframework.beans.factory.BeanFactoryUtils;
 import org.springframework.beans.factory.InitializingBean;
@@ -56,6 +59,8 @@ public class LensJLineShellComponent extends JLineShell
   private ExecutionStrategy executionStrategy = new LensSimpleExecutionStrategy();
   private SimpleParser parser = new SimpleParser();
 
+  private static final Logger LOGGER = LoggerFactory.getLogger(LensJLineShellComponent.class);
+
   public SimpleParser getSimpleParser() {
     return parser;
   }
@@ -123,7 +128,7 @@ public void waitForComplete() {
     try {
       shellThread.join();
     } catch (InterruptedException e) {
-      e.printStackTrace();
+      LOGGER.error(e.toString(), e);
     }
   }
 

markdown/src/main/java/org/apache/zeppelin/markdown/Markdown.java

@@ -29,12 +29,15 @@
 import org.apache.zeppelin.scheduler.Scheduler;
 import org.apache.zeppelin.scheduler.SchedulerFactory;
 import org.markdown4j.Markdown4jProcessor;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * Markdown interpreter for Zeppelin.
  */
 public class Markdown extends Interpreter {
   private Markdown4jProcessor md;
+  static final Logger LOGGER = LoggerFactory.getLogger(Markdown.class);
 
   static {
     Interpreter.register("md", Markdown.class.getName());
@@ -58,6 +61,7 @@ public InterpreterResult interpret(String st, InterpreterContext interpreterCont
     try {
       html = md.process(st);
     } catch (IOException | java.lang.RuntimeException e) {
+      LOGGER.error("Exception in Markdown while interpret ", e);
       return new InterpreterResult(Code.ERROR, InterpreterUtils.getMostRelevantMessage(e));
     }
     return new InterpreterResult(Code.SUCCESS, "%html " + html);

postgresql/src/main/java/org/apache/zeppelin/postgresql/PostgreSqlInterpreter.java

@@ -297,6 +297,7 @@ public void cancel(InterpreterContext context) {
       try {
         currentStatement.cancel();
       } catch (SQLException ex) {
+        logger.error("SQLException in PostgreSqlInterpreter while cancel ", ex);
       } finally {
         currentStatement = null;
       }

spark/src/main/java/org/apache/zeppelin/spark/DepInterpreter.java

@@ -41,6 +41,8 @@
 import org.apache.zeppelin.interpreter.WrappedInterpreter;
 import org.apache.zeppelin.scheduler.Scheduler;
 import org.apache.zeppelin.spark.dep.DependencyContext;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.sonatype.aether.resolution.ArtifactResolutionException;
 import org.sonatype.aether.resolution.DependencyResolutionException;
 
@@ -80,6 +82,7 @@ public class DepInterpreter extends Interpreter {
   private DependencyContext depc;
   private SparkJLineCompletion completor;
   private SparkILoop interpreter;
+  static final Logger LOGGER = LoggerFactory.getLogger(DepInterpreter.class);
 
   public DepInterpreter(Properties property) {
     super(property);
@@ -195,6 +198,7 @@ public InterpreterResult interpret(String st, InterpreterContext context) {
       depc.fetch();
     } catch (MalformedURLException | DependencyResolutionException
         | ArtifactResolutionException e) {
+      LOGGER.error("Exception in DepInterpreter while interpret ", e);
       return new InterpreterResult(Code.ERROR, e.toString());
     }
 

spark/src/main/java/org/apache/zeppelin/spark/SparkInterpreter.java

@@ -82,7 +82,7 @@
  *
  */
 public class SparkInterpreter extends Interpreter {
-  Logger logger = LoggerFactory.getLogger(SparkInterpreter.class);
+  public static Logger logger = LoggerFactory.getLogger(SparkInterpreter.class);
 
   static {
     Interpreter.register(
@@ -186,7 +186,7 @@ static JobProgressListener setupListeners(SparkContext context) {
       }
     } catch (NoSuchMethodException | SecurityException | IllegalAccessException
         | IllegalArgumentException | InvocationTargetException e) {
-      e.printStackTrace();
+      logger.error(e.toString(), e);
       return null;
     }
     return pl;

spark/src/test/java/org/apache/zeppelin/spark/SparkInterpreterTest.java

@@ -38,12 +38,15 @@
 import org.junit.FixMethodOrder;
 import org.junit.Test;
 import org.junit.runners.MethodSorters;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 @FixMethodOrder(MethodSorters.NAME_ASCENDING)
 public class SparkInterpreterTest {
   public static SparkInterpreter repl;
   private InterpreterContext context;
   private File tmpDir;
+  public static Logger LOGGER = LoggerFactory.getLogger(SparkInterpreterTest.class);
 
 
   /**
@@ -177,7 +180,7 @@ public void emptyConfigurationVariablesOnlyForNonSparkProperties() {
     for (Object oKey : intpProperty.keySet()) {
       String key = (String) oKey;
       String value = (String) intpProperty.get(key);
-      repl.logger.debug(String.format("[%s]: [%s]", key, value));
+      LOGGER.debug(String.format("[%s]: [%s]", key, value));
       if (key.startsWith("spark.") && value.isEmpty()) {
         assertTrue(String.format("configuration starting from 'spark.' should not be empty. [%s]", key), !sparkConf.contains(key) || !sparkConf.get(key).isEmpty());
       }

spark/src/test/java/org/apache/zeppelin/spark/SparkSqlInterpreterTest.java

@@ -33,6 +33,8 @@
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 public class SparkSqlInterpreterTest {
 
@@ -41,6 +43,8 @@ public class SparkSqlInterpreterTest {
   private InterpreterContext context;
   private InterpreterGroup intpGroup;
 
+  Logger LOGGER = LoggerFactory.getLogger(SparkSqlInterpreterTest.class);
+
   @Before
   public void setUp() throws Exception {
     Properties p = new Properties();
@@ -96,6 +100,7 @@ public void test() {
       fail("Exception not catched");
     } catch (Exception e) {
       // okay
+      LOGGER.info("Exception in SparkSqlInterpreterTest while test ", e);
     }
     assertEquals(InterpreterResult.Code.SUCCESS, sql.interpret("select case when name==\"aa\" then name else name end from test", context).code());
   }

tajo/src/test/java/org/apache/zeppelin/tajo/TesterResultSet.java

@@ -17,20 +17,26 @@
  */
 package org.apache.zeppelin.tajo;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.InputStream;
+import java.io.Reader;
+import java.io.UnsupportedEncodingException;
 import java.math.BigDecimal;
 import java.sql.*;
 import java.util.Calendar;
 import java.util.Map;
-import java.io.InputStream;
-import java.io.Reader;
-import java.io.UnsupportedEncodingException;
 
 /**
  * This is borrowed from Apache Commons DBCP2.
  *
  * A dummy {@link java.sql.ResultSet}, for testing purposes.
  */
 public class TesterResultSet implements ResultSet {
+
+  Logger LOGGER = LoggerFactory.getLogger(TesterResultSet.class);
+
   public TesterResultSet(Statement stmt) {
     _statement = stmt;
   }
@@ -262,6 +268,8 @@ public byte[] getBytes(String columnName) throws SQLException {
       return columnName.getBytes("UTF-8");
     } catch (UnsupportedEncodingException e) {
       // Impossible. JVMs are required to support UTF-8
+      LOGGER.error("Exception in TesterResultSet while getBytes, Impossible. JVMs are required to" +
+          " support UTF-8", e);
       return null;
     }
   }

zeppelin-interpreter/src/main/java/org/apache/zeppelin/interpreter/Interpreter.java

@@ -131,7 +131,7 @@ public void destroy() {
 
 
 
-  static Logger logger = LoggerFactory.getLogger(Interpreter.class);
+  public static Logger logger = LoggerFactory.getLogger(Interpreter.class);
   private InterpreterGroup interpreterGroup;
   private URL [] classloaderUrls;
   protected Properties property;

zeppelin-interpreter/src/main/java/org/apache/zeppelin/interpreter/InterpreterGroup.java

@@ -33,6 +33,8 @@
 public class InterpreterGroup extends LinkedList<Interpreter>{
   String id;
 
+  Logger LOGGER = Logger.getLogger(InterpreterGroup.class);
+
   AngularObjectRegistry angularObjectRegistry;
   RemoteInterpreterProcess remoteInterpreterProcess;    // attached remote interpreter process
 
@@ -100,8 +102,7 @@ public void run() {
       try {
         t.join();
       } catch (InterruptedException e) {
-        Logger logger = Logger.getLogger(InterpreterGroup.class);
-        logger.error("Can't close interpreter", e);
+        LOGGER.error("Can't close interpreter", e);
       }
     }
   }
@@ -124,8 +125,7 @@ public void run() {
       try {
         t.join();
       } catch (InterruptedException e) {
-        Logger logger = Logger.getLogger(InterpreterGroup.class);
-        logger.error("Can't close interpreter", e);
+        LOGGER.error("Can't close interpreter", e);
       }
     }
 

zeppelin-interpreter/src/main/java/org/apache/zeppelin/interpreter/remote/RemoteAngularObjectRegistry.java

@@ -101,7 +101,6 @@ public AngularObject addAndNotifyRemoteProcess(String name, Object o, String not
    * this method should be used instead of remove()
    * @param name
    * @param noteId
-   * @param emit
    * @return
    */
   public AngularObject removeAndNotifyRemoteProcess(String name, String noteId) {

zeppelin-interpreter/src/main/java/org/apache/zeppelin/interpreter/remote/RemoteInterpreterEventPoller.java

@@ -124,6 +124,7 @@ private void waitQuietly() {
         wait(1000);
       }
     } catch (InterruptedException ignored) {
+      logger.info("Error in RemoteInterpreterEventPoller while waitQuietly : ", ignored);
     }
   }
 

zeppelin-interpreter/src/main/java/org/apache/zeppelin/interpreter/remote/RemoteInterpreterProcess.java

@@ -121,6 +121,8 @@ public int reference(InterpreterGroup interpreterGroup) {
             try {
               Thread.sleep(500);
             } catch (InterruptedException e) {
+              logger.error("Exception in RemoteInterpreterProcess while synchronized reference " +
+                  "Thread.sleep", e);
             }
           }
         }
@@ -177,6 +179,8 @@ public int dereference() {
           client.shutdown();
         } catch (Exception e) {
           // safely ignore exception while client.shutdown() may terminates remote process
+          logger.info("Exception in RemoteInterpreterProcess while synchronized dereference, can " +
+              "safely ignore exception while client.shutdown() may terminates remote process", e);
         } finally {
           if (client != null) {
             // no longer used
@@ -195,6 +199,8 @@ public int dereference() {
             try {
               Thread.sleep(500);
             } catch (InterruptedException e) {
+              logger.error("Exception in RemoteInterpreterProcess while synchronized dereference " +
+                  "Thread.sleep", e);
             }
           } else {
             break;
@@ -266,6 +272,8 @@ public void updateRemoteAngularObject(String name, String noteId, Object o) {
       client = getClient();
     } catch (NullPointerException e) {
       // remote process not started
+      logger.info("NullPointerException in RemoteInterpreterProcess while " +
+          "updateRemoteAngularObject getClient, remote process not started", e);
       return;
     } catch (Exception e) {
       logger.error("Can't update angular object", e);

zeppelin-interpreter/src/main/java/org/apache/zeppelin/interpreter/remote/RemoteInterpreterServer.java

@@ -114,6 +114,7 @@ public void shutdown() throws TException {
       try {
         Thread.sleep(300);
       } catch (InterruptedException e) {
+        logger.info("Exception in RemoteInterpreterServer while shutdown, Thread.sleep", e);
       }
     }
 
@@ -170,7 +171,7 @@ public void createInterpreter(String className, Map<String, String> properties)
     } catch (ClassNotFoundException | NoSuchMethodException | SecurityException
         | InstantiationException | IllegalAccessException
         | IllegalArgumentException | InvocationTargetException e) {
-      e.printStackTrace();
+      logger.error(e.toString(), e);
       throw new TException(e);
     }
   }
@@ -225,6 +226,7 @@ public RemoteInterpreterResult interpret(String className, String st,
         try {
           jobListener.wait(1000);
         } catch (InterruptedException e) {
+          logger.info("Exception in RemoteInterpreterServer while interpret, jobListener.wait", e);
         }
       }
     }
@@ -455,6 +457,7 @@ public RemoteInterpreterEvent getEvent() throws TException {
         try {
           eventQueue.wait(1000);
         } catch (InterruptedException e) {
+          logger.info("Exception in RemoteInterpreterServer while getEvent, eventQueue.wait", e);
         }
       }
 
@@ -468,7 +471,6 @@ public RemoteInterpreterEvent getEvent() throws TException {
 
   /**
    * called when object is updated in client (web) side.
-   * @param className
    * @param name
    * @param noteId noteId where the update issues
    * @param object
@@ -499,6 +501,7 @@ public void angularObjectUpdate(String name, String noteId, String object)
         return;
       } catch (Exception e) {
         // no luck
+        logger.info("Exception in RemoteInterpreterServer while angularObjectUpdate, no luck", e);
       }
     }
 
@@ -510,6 +513,7 @@ public void angularObjectUpdate(String name, String noteId, String object)
           }.getType());
       } catch (Exception e) {
         // no lock
+        logger.info("Exception in RemoteInterpreterServer while angularObjectUpdate, no lock", e);
       }
     }
 
@@ -544,6 +548,7 @@ public void angularObjectAdd(String name, String noteId, String object)
           }.getType());
     } catch (Exception e) {
       // nolock
+      logger.info("Exception in RemoteInterpreterServer while angularObjectAdd, nolock", e);
     }
 
     // try string object type at last