added new NPE checks, asserts and timestamps checks

Author: bhuvnesh17

src/main/java/com/appdynamics/extensions/sql/JDBCConnectionAdapter.java

@@ -9,6 +9,7 @@
 
 
 import com.google.common.base.Strings;
+import org.slf4j.LoggerFactory;
 
 import java.sql.*;
 import java.util.Map;
@@ -19,6 +20,7 @@ public class JDBCConnectionAdapter {
 
     private final String connUrl;
     private final Map<String, String> connectionProperties;
+    private static final org.slf4j.Logger logger = LoggerFactory.getLogger(JDBCConnectionAdapter.class);
 
 
     private JDBCConnectionAdapter(String connStr, Map<String, String> connectionProperties) {
@@ -43,7 +45,13 @@ Connection open(String driver) throws SQLException, ClassNotFoundException {
                     properties.put(key, connectionProperties.get(key));
             }
         }
+
+        logger.debug("Passed all checks for properties and attempting to connect to: "+ connUrl);
+        long timestamp1 = System.currentTimeMillis();
         connection = DriverManager.getConnection(connUrl, properties);
+        long timestamp2 = System.currentTimeMillis();
+        logger.debug("Connection received in JDBC ConnectionAdapter in :"+ (timestamp2-timestamp1)+ " ms");
+
         return connection;
     }
 

src/main/java/com/appdynamics/extensions/sql/SQLMonitor.java

@@ -11,6 +11,7 @@
 import com.appdynamics.extensions.TaskInputArgs;
 import com.appdynamics.extensions.TasksExecutionServiceProvider;
 import com.appdynamics.extensions.crypto.CryptoUtil;
+import com.appdynamics.extensions.util.AssertUtils;
 import com.appdynamics.extensions.util.StringUtils;
 import com.google.common.base.Strings;
 import com.google.common.collect.Maps;
@@ -74,6 +75,12 @@ protected int getTaskCount() {
 
     private SQLMonitorTask createTask(Map server, TasksExecutionServiceProvider serviceProvider) throws IOException {
         String connUrl = createConnectionUrl(server);
+
+        AssertUtils.assertNotNull(serverName(server), "The 'displayName' field under the 'dbServers' section in config.yml is not initialised");
+        AssertUtils.assertNotNull(createConnectionUrl(server), "The 'connectionUrl' field under the 'dbServers' section in config.yml is not initialised");
+        AssertUtils.assertNotNull(driverName(server), "The 'driver' field under the 'dbServers' section in config.yml is not initialised");
+
+
         Map<String, String> connectionProperties = getConnectionProperties(server);
         JDBCConnectionAdapter jdbcAdapter = JDBCConnectionAdapter.create(connUrl, connectionProperties);
 
@@ -87,6 +94,16 @@ private SQLMonitorTask createTask(Map server, TasksExecutionServiceProvider serv
 
     }
 
+    private String serverName(Map server) {
+        String name = Util.convertToString(server.get("displayName"), "");
+        return name;
+    }
+
+    private String driverName(Map server) {
+        String name = Util.convertToString(server.get("driver"), "");
+        return name;
+    }
+
     private String createConnectionUrl(Map server) {
         String url = Util.convertToString(server.get("connectionUrl"), "");
         return url;
@@ -116,7 +133,6 @@ private Map<String, String> getConnectionProperties(Map server) {
                 }
             }
             return connectionProperties;
-
         }
 
         return null;

src/main/java/com/appdynamics/extensions/sql/SQLMonitorTask.java

@@ -36,14 +36,26 @@ public void run() {
         Connection connection = null;
         if (queries != null && !queries.isEmpty()) {
             try {
+                long timestamp1 = System.currentTimeMillis();
                 connection = getConnection();
-                for (Map query : queries) {
-                    try {
-                        executeQuery(connection, query);
-                    } catch (SQLException e) {
-                        logger.error("Error during executing query.");
+                long timestamp2 = System.currentTimeMillis();
+                logger.debug("Time taken to get Connection: " + (timestamp2 - timestamp1));
+                String dbServerDisplayName = (String) server.get("displayName");
+                if(connection != null) {
+                    logger.debug(" Connection successful for server: " + dbServerDisplayName);
+
+                    for (Map query : queries) {
+                        try {
+                            executeQuery(connection, query);
+                        } catch (SQLException e) {
+                            logger.error("Error during executing query.");
+                        }
                     }
+                } else {
+
+                    logger.debug("Null Connection returned for server: " + dbServerDisplayName);
                 }
+
             } catch (SQLException e) {
                 logger.error("Error Opening connection", e);
                 status = false;
@@ -52,7 +64,9 @@ public void run() {
                 status = false;
             } finally {
                 try {
-                    closeConnection(connection);
+                    if (connection != null) {
+                        closeConnection(connection);
+                    }
                 } catch (Exception e) {
                     logger.error("Issue closing the connection", e);
                 }
@@ -108,7 +122,11 @@ private ResultSet getResultSet(Map query, Statement statement, ResultSet resultS
         String queryStmt = (String) query.get("queryStmt");
         queryStmt = substitute(queryStmt);
 
+        long timestamp1 = System.currentTimeMillis();
         resultSet = jdbcAdapter.queryDatabase(queryStmt, statement);
+        long timestamp2 = System.currentTimeMillis();
+
+        logger.debug("Queried the database in :"+ (timestamp2-timestamp1)+ " ms for query: \n " +  queryStmt);
         return resultSet;
     }