java.lang.Object
jdk.jfr.Configuration
A collection of settings and metadata describing the configuration.
The following example shows how the Configuration
class can be used
to list available configurations and how to pass a configuration object to a
Recording
.
public static void main(String... args) throws Exception {
if (args.length == 0) {
System.out.println("Configurations:");
for (Configuration c : Configuration.getConfigurations()) {
System.out.println("Name: " + c.getName());
System.out.println("Label: " + c.getLabel());
System.out.println("Description: " + c.getDescription());
System.out.println("Provider: " + c.getProvider());
System.out.println();
}
} else {
String name = args[0];
Configuration c = Configuration.getConfiguration(name);
try (Recording r = new Recording(c)) {
System.out.println("Starting recording with settings:");
for (Map.Entry<String, String> setting : c.getSettings().entrySet()) {
System.out.println(setting.getKey() + " = " + setting.getValue());
}
r.start();
}
}
}
- Since:
- 9
-
Method Summary
Modifier and TypeMethodDescriptionstatic Configuration
Reads a configuration from a character stream.static Configuration
Reads a configuration from a file.static Configuration
getConfiguration
(String name) Returns a predefined configuration.static List
<Configuration> Returns an immutable list of predefined configurations for this Java Virtual Machine (JVM).Returns a textual representation of the configuration (for example, the contents of a JFC file).Returns a short sentence that describes the configuration (for example"Low overhead configuration safe for continuous use in production environments"
)getLabel()
Returns a human-readable name (for example,"Continuous" or "Profiling"
}.getName()
Returns an identifying name (for example,"default" or "profile")
.Returns who created the configuration (for example"OpenJDK"
).Returns the settings that specifies how a recording is configured.
-
Method Details
-
getSettings
Returns the settings that specifies how a recording is configured.Modifying the returned
Map
object doesn't change the configuration.- Returns:
- settings, not
null
-
getName
Returns an identifying name (for example,"default" or "profile")
.- Returns:
- the name, or
null
if it doesn't exist
-
getLabel
Returns a human-readable name (for example,"Continuous" or "Profiling"
}.- Returns:
- the label, or
null
if it doesn't exist
-
getDescription
Returns a short sentence that describes the configuration (for example"Low overhead configuration safe for continuous use in production environments"
)- Returns:
- the description, or
null
if it doesn't exist
-
getProvider
Returns who created the configuration (for example"OpenJDK"
).- Returns:
- the provider, or
null
if it doesn't exist
-
getContents
Returns a textual representation of the configuration (for example, the contents of a JFC file).- Returns:
- contents, or
null
if it doesn't exist - See Also:
-
create
Reads a configuration from a file.- Parameters:
path
- the file that contains the configuration, notnull
- Returns:
- the read
Configuration
, notnull
- Throws:
ParseException
- if the file can't be parsedIOException
- if the file can't be readSecurityException
- if a security manager exists and itscheckRead
method denies read access to the file.- See Also:
-
create
Reads a configuration from a character stream.- Parameters:
reader
- aReader
that provides the configuration contents, notnull
- Returns:
- a configuration, not
null
- Throws:
IOException
- if an I/O error occurs while trying to read contents from theReader
ParseException
- if the file can't be parsed
-
getConfiguration
Returns a predefined configuration.See
getConfigurations()
for available configuration names.- Parameters:
name
- the name of the configuration (for example,"default"
or"profile"
)- Returns:
- a configuration, not
null
- Throws:
IOException
- if a configuration with the given name does not exist, or if an I/O error occurs while reading the configuration fileParseException
- if the configuration file can't be parsed
-
getConfigurations
Returns an immutable list of predefined configurations for this Java Virtual Machine (JVM).- Returns:
- the list of predefined configurations, not
null
-