UCP leverages the JDK logging facility (
java.util.logging). Logging is not enabled by default and must be configured in order to print log messages. Logging can be configured using a log configuration file as well as through API-level configuration.
The default log level is
null. This ensures that a parent logger's log level is used by default.
12.4.1 Using a Logging Properties File
The logging properties file defines the handler to use for writing logs, the formatter to use for formatting logs, a default log level, as well as log levels for specific packages or classes. For example:
handlers = java.util.logging.ConsoleHandler java.util.logging.ConsoleHandler.level = ALL java.util.logging.ConsoleHandler.formatter = java.util.logging.SimpleFormatter oracle.ucp.level = FINEST oracle.ucp.jdbc.PoolDataSource = WARNING
A custom formatter is included with UCP and can be entered as the value for the formatter property. For example:
java.util.logging.ConsoleHandler.formatter = oracle.ucp.util.logging.UCPFormatter
You can also download the
ucpdemos.jar file, which is shipped with UCP, from Oracle Technology Network (OTN). This file contains a list of sample logging property files. For example, this file contains the logging property file that can be used for troubleshooting the Fast Connection Failover (FCF) feature.
12.4.2 Using UCP and JDK API
Logging can be dynamically configured though either the UCP API or the JDK API. When using the UCP API, logging is configured using a connection pool manager. When using the JDK, logging is configured using the
The following example demonstrates using the UCP API to configure logging:
UniversalConnectionPoolManager mgr = UniversalConnectionPoolManagerImpl. getUniversalConnectionPoolManager(); mgr.setLogLevel(Level.FINE);
The following example demonstrate using the JDK logging implementation directly:
12.4.3 Enabling or Disabling Feature-Specific Logging at Runtime
Starting from Oracle Database 12c Release 2 (18.104.22.168), UCP provides support for enabling and disabling logging for selected features during runtime. For example, you can enable logging only for Load Balancing feature, while disabling logging for other features of UCP. Again, during the same run, you can enable logging for Fast Failover feature and disable logging for Load Balancing feature.
By default, logging for all features is enabled.
The logging switching feature of UCP is a part of the
OracleDiagnosabilityMBean. For using this bean, start JConsole and connect to the application.
For a list of supported features, use the following method:
For a list of currently enabled features, use the following method:
For enabling logging for a specific feature or for all features, use the
trace method in the following ways:
trace(boolean enable, String feature_name) trace(boolean enable, ALL)
For disabling logging for a specific feature or for all features, use the
trace method in the following ways:
trace(boolean disable, String feature_name) trace(boolean disable, ALL)
Use the following methods for suspending and resuming logging respectively:
12.4.4 About Using the Logging Properties File for Feature-Specific Logging
Starting from Oracle Database 12c Release 2 (22.214.171.124), you can enable or disable logging for specific features by adding a property in the logging properties file. By default, logging is enabled for all features. Otherwise, you can enable logging for all features using the following syntax:
clio.feature.all = on. For feature-specific enabling of logging, you can use the properties as mentioned in the following section:
Supported Features for feature-Based Granularity
clio.feature.pool_statistics = on clio.feature.check_in = on clio.feature.check_out = on clio.feature.labeling = on clio.feature.conn_construction = on clio.feature.conn_destruction = on clio.feature.high_availability = on clio.feature.load_balancing = on clio.feature.transaction_affinity = on clio.feature.web_affinity = on clio.feature.data_affinity = on clio.feature.conn_harvesting = on clio.feature.ttl_conn_timeout = on clio.feature.abandoned_conn_timeout = on clio.feature.admin = on clio.feature.sharding = on
12.4.5 Supported Log Levels
The following list describes each of the log levels that are supported for JDBC. Levels lower than
FINE produce output that may not be meaningful to users. Levels lower than
FINER will produce very large volumes of output.
INTERNAL_ERROR– Internal Errors
SEVERE– SQL Exceptions
WARNING– SQL Warnings and other invisible problems
INFO– Public events such as connection attempts or Oracle RAC events
CONFIG– SQL statements
FINE– Public APIs
TRACE_10– Internal events
FINER– Internal APIs
TRACE_20– Internal debug
TRACE_30– High volume internal APIs
FINEST– High volume internal debug