monetdb-java: src/main/java/org/monetdb/jdbc/MonetConnection.java comparison

comparison src/main/java/org/monetdb/jdbc/MonetConnection.java @ 408:5540793628d6

Improve code when setting query timeout. It used to call the sys.settimeout(bigint) which is deprecated as of release Jun2020 (11.37.7) and replaced by new sys.setquerytimeout(int). As the server call was done from two places MonetConnection.isValid() and MonetStatement.internalExecute(), I created a single utlity method which is now called instead.

author	Martin van Dinther <martin.van.dinther@monetdbsolutions.com>
date	Thu, 07 Jan 2021 21:31:03 +0100 (2021-01-07)
parents	40a1db14dca5
children	1e278695fe54

comparison

equal deleted inserted replaced

-:40a1db14dca5
+:5540793628d6
 	private boolean treatBlobAsVarBinary = true;
 	/** Whether or not CLOB is mapped to Types.VARCHAR instead of Types.CLOB within this connection */
 	private boolean treatClobAsVarChar = true;
 	/** The last set query timeout on the server as used by Statement, PreparedStatement and CallableStatement */
-	protected int lastSetQueryTimeout = 0;	// 0 means no timeout, which is the default on the server
+	protected int lastSetQueryTimeout;	// 0 means no timeout, which is the default on the server
 	/**
 	 * Constructor of a Connection for MonetDB. At this moment the
 	 * current implementation limits itself to storing the given host,
 				if (rs != null && rs.next()) {
 					isValid = true;
 				}
 			}
 		} catch (SQLException se) {
-			String msg = se.getMessage();
+			final String msg = se.getMessage();
 			// System.out.println(se.getSQLState() + " Con.isValid(): " + msg);
 			if (msg != null && msg.equalsIgnoreCase("Current transaction is aborted (please ROLLBACK)")) {
 				// Must use equalsIgnoreCase() here because up to Jul2017 release 'Current' was 'current' so with lowercase c.
 				// It changed to 'Current' after Jul2017 release. We need to support all server versions.
 				// SQLState = 25005
 				isValid = true;
 			}
 			/* ignore stmt errors/exceptions, we are only testing if the connection is still alive and usable */
 		} finally {
+			closeResultsetStatement(rs, stmt);
 			/* when changed, reset the original server timeout value on the server */
 			if (timeout > 0 && original_timeout != this.lastSetQueryTimeout) {
 				this.lastSetQueryTimeout = original_timeout;
-				Statement stmt2 = null;
 				try {
 					/* we have to set in the server explicitly, because the test 'queryTimeout != connection.lastSetQueryTimeout'
 					   on MonetStatement.internalExecute(sql) won't pass and the server won't be set back */
-					stmt2 = this.createStatement();
+					setQueryTimeout(original_timeout);
-					stmt2.execute("CALL \"sys\".\"settimeout\"(" + this.lastSetQueryTimeout + ")");
 				} catch (SQLException se) {
 					/* ignore stmt errors/exceptions, we are only testing if the connection is still alive and usable */
-				} finally {
-					closeResultsetStatement(null, stmt2);
 				}
 			}
-			closeResultsetStatement(rs, stmt);
 		}
 		return isValid;
 	}
 	/**
 	//== internal helper methods which do not belong to the JDBC interface
 	/**
+	 * Local helper method to test whether the Connection object is closed
+	 * When closed it throws an SQLException
+	 */
+	private void checkNotClosed() throws SQLException {
+		if (closed)
+			throw new SQLException("Connection is closed", "M1M20");
+	}
+	/**
+	 * Utility method to call sys.setquerytimeout(int); procedure on the connected server.
+	 * It is called from: MonetConnection.isValid() and MonetStatement.internalExecute()
+	 */
+	void setQueryTimeout(final int millis) throws SQLException {
+		if (millis < 0)
+			throw new SQLException("query timeout milliseconds is less than zero", "M1M05");
+		checkNotClosed();
+		Statement st = null;
+		try {
+			// as of release Jun2020 (11.37.7) the function sys.settimeout(bigint) is deprecated and replaced by new sys.setquerytimeout(int)
+			final boolean postJun2020 = (getDatabaseMajorVersion() >=11) && (getDatabaseMinorVersion() >= 37);
+			final String callstmt = postJun2020 ? "CALL sys.\"setquerytimeout\"(" + millis + ")"
+							    : "CALL sys.\"settimeout\"(" + millis + ")";
+			// for debug: System.out.println("Before: " + callstmt);
+			st = createStatement();
+			st.execute(callstmt);
+			// for debug: System.out.println("After : " + callstmt);
+			this.lastSetQueryTimeout = millis;
+		}
+		/* do not catch SQLException here, as we want to know it when it fails */
+		finally {
+			closeResultsetStatement(null, st);
+		}
+	}
+	/**
 	 * @return whether the JDBC BLOB type should be mapped to VARBINARY type.
 	 * This allows generic JDBC programs to fetch Blob data via getBytes()
 	 * instead of getBlob() and Blob.getBinaryStream() to reduce overhead.
 	 * It is called from: MonetResultSet and MonetPreparedStatement
 	 */
 	 * instead of getClob() and Clob.getCharacterStream() to reduce overhead.
 	 * It is called from: MonetResultSet and MonetPreparedStatement
 	 */
 	boolean mapClobAsVarChar() {
 		return treatClobAsVarChar;
-	}
-	/**
-	 * Local helper method to test whether the Connection object is closed
-	 * When closed it throws an SQLException
-	 */
-	private void checkNotClosed() throws SQLException {
-		if (closed)
-			throw new SQLException("Connection is closed", "M1M20");
 	}
 	/**
 	 * @return the MonetDB JDBC Connection URL (without user name and password).
 	 * It is called from: getURL()in MonetDatabaseMetaData
 	// Internal caches for 3 static mserver environment values, so they aren't queried from mserver again and again
 	private String env_current_user;
 	private String env_monet_version;
 	private int maxConnections;
-	private int databaseMajorVersion;
-	private int databaseMinorVersion;
 	/**
 	 * Utility method to fetch 3 mserver environment values combined in one query for efficiency.
 	 * We currently fetch the env values of: current_user, monet_version and max_clients.
 	 * We cache them such that we do not need to query the server again and again.
 			getEnvValues();
 		return env_current_user;
 	}
 	/**
+	 * @return the maximum number of active connections possible at one time;
+	 * a result of zero means that there is no limit or the limit is not known
+	 * It is called from: MonetDatabaseMetaData
+	 */
+	int getMaxConnections() throws SQLException {
+		if (maxConnections == 0)
+			getEnvValues();
+		return maxConnections;
+	}
+	/**
 	 * @return the MonetDB Database Server version string.
 	 * It is called from: MonetDatabaseMetaData
 	 */
 	String getDatabaseProductVersion() throws SQLException {
 		if (env_monet_version == null)
 		if (env_monet_version != null)
 			return env_monet_version;
 		return "";
 	}
+	private int databaseMajorVersion;
 	/**
 	 * @return the MonetDB Database Server major version number.
-	 * It is called from: MonetDatabaseMetaData
+	 * The number is extracted from the env_monet_version the first time and cached for next calls.
+	 * It is called from: MonetDatabaseMetaData and MonetConnection
 	 */
 	int getDatabaseMajorVersion() throws SQLException {
 		if (databaseMajorVersion == 0) {
 			if (env_monet_version == null)
 				getEnvValues();
 			}
 		}
 		return databaseMajorVersion;
 	}
+	private int databaseMinorVersion;
 	/**
 	 * @return the MonetDB Database Server minor version number.
-	 * It is called from: MonetDatabaseMetaData
+	 * The number is extracted from the env_monet_version the first time and cached for next calls.
+	 * It is called from: MonetDatabaseMetaData and MonetConnection
 	 */
 	int getDatabaseMinorVersion() throws SQLException {
 		if (databaseMinorVersion == 0) {
 			if (env_monet_version == null)
 				getEnvValues();
 					// ignore
 				}
 			}
 		}
 		return databaseMinorVersion;
-	}
-	/**
-	 * @return the maximum number of active connections possible at one time;
-	 * a result of zero means that there is no limit or the limit is not known
-	 * It is called from: MonetDatabaseMetaData
-	 */
-	int getMaxConnections() throws SQLException {
-		if (maxConnections == 0)
-			getEnvValues();
-		return maxConnections;
 	}
 	// Internal cache for determining if system table sys.privilege_codes (new as of Jul2017 release) exists on connected server
 	private boolean queriedPrivilege_codesTable = false;
 		private final boolean cacheSizeSetExplicitly;
 		/** Whether we should send an Xclose command to the server
 		 *  if we close this Response */
 		private boolean destroyOnClose;
 		/** the offset to be used on Xexport queries */
-		private int blockOffset = 0;
+		private int blockOffset;
 		/** A parser for header lines */
 		private final HeaderLineParser hlp;
 		/** A boolean array telling whether the headers are set or not */
 		private final boolean[] isSet;
-		private static final int NAMES	= 0;
+		private static final int NAMES  = 0;
-		private static final int TYPES	= 1;
+		private static final int TYPES  = 1;
-		private static final int TABLES	= 2;
+		private static final int TABLES = 2;
-		private static final int LENS	= 3;
+		private static final int LENS   = 3;
 		/**
 		 * Sole constructor, which requires a MonetConnection parent to
 		 * be given.

Mercurial > hg > monetdb-java

comparison src/main/java/org/monetdb/jdbc/MonetConnection.java @ 408:5540793628d6