java.lang.management
Interface RuntimeMBean

public interface RuntimeMBean

The management interface for the runtime system of the Java virtual machine.

A Java virtual machine has a single instance of the implementation class of this interface. This instance implementing this interface is a managed bean (MBean) conforming to the JMX Instrumentation Specification. The MBean can be obtained by calling the ManagementFactory.getRuntimeMBean() method. An application can monitor the instrumentation of the runtime system and manage certain characteristics in any of the following ways:

• Call the methods of the MBean directly.
• Go through the MBeanServer.
• Construct an MBean proxy and call the methods of the MBean proxy.

The ManagementFactory.getPlatformMBeanServer() method returns the platform MBeanServer registered with all platform MBeans.

The ObjectName for uniquely identifying the MBean for the runtime system within an MBeanServer is:

java.lang:type=Runtime

This interface defines several convenient methods for accessing system properties about the Java virtual machine.

Since:

1.5

See Also:

Ways to Access Management Metrics

getName

String getName()

Returns the name representing the running Java virtual machine. The returned name string can be any arbitrary string and a Java virtual machine implementation can choose to embed platform-specific useful information in the returned name string. Each running virtual machine could have a different name.

Returns:

the name representing the running Java virtual machine.

getVmName

String getVmName()

Returns the Java virtual machine implementation name. This method is equivalent to System.getProperty("java.vm.name").

Returns:

the Java virtual machine implementation name.

Throws:

SecurityException - if a security manager exists and its checkPropertiesAccess method doesn't allow access to this system property.

See Also:

SecurityManager.checkPropertyAccess(java.lang.String), System.getProperty(java.lang.String)

getVmVendor

String getVmVendor()

Returns the Java virtual machine implementation vendor. This method is equivalent to System.getProperty("java.vm.vendor").

Returns:

the Java virtual machine implementation vendor.

Throws:

SecurityException - if a security manager exists and its checkPropertiesAccess method doesn't allow access to this system property.

See Also:

SecurityManager.checkPropertyAccess(java.lang.String), System.getProperty(java.lang.String)

getVmVersion

String getVmVersion()

Returns the Java virtual machine implementation version. This method is equivalent to System.getProperty("java.vm.version").

Returns:

the Java virtual machine implementation version.

Throws:

SecurityException - if a security manager exists and its checkPropertiesAccess method doesn't allow access to this system property.

See Also:

SecurityManager.checkPropertyAccess(java.lang.String), System.getProperty(java.lang.String)

getSpecName

String getSpecName()

Returns the Java virtual machine specification name. This method is equivalent to System.getProperty("java.vm.specification.name").

Returns:

the Java virtual machine specification name.

Throws:

SecurityException - if a security manager exists and its checkPropertiesAccess method doesn't allow access to this system property.

See Also:

SecurityManager.checkPropertyAccess(java.lang.String), System.getProperty(java.lang.String)

getSpecVendor

String getSpecVendor()

Returns the Java virtual machine specification vendor. This method is equivalent to System.getProperty("java.vm.specification.vendor").

Returns:

the Java virtual machine specification vendor.

Throws:

SecurityException - if a security manager exists and its checkPropertiesAccess method doesn't allow access to this system property.

See Also:

SecurityManager.checkPropertyAccess(java.lang.String), System.getProperty(java.lang.String)

getSpecVersion

String getSpecVersion()

Returns the Java virtual machine specification version. This method is equivalent to System.getProperty("java.vm.specification.version").

Returns:

the Java virtual machine specification version.

Throws:

SecurityException - if a security manager exists and its checkPropertiesAccess method doesn't allow access to this system property.

See Also:

SecurityManager.checkPropertyAccess(java.lang.String), System.getProperty(java.lang.String)

getManagementSpecVersion

String getManagementSpecVersion()

Returns the version of the specification for the management interface implemented by the running Java virtual machine.

Returns:

the version of the specification for the management interface implemented by the running Java virtual machine.

getClassPath

String getClassPath()

Returns the Java class path that is used by the system class loader to search for class files. This method is equivalent to System.getProperty("java.class.path").

Multiple paths in the Java class path are separated by the path separator character of the platform of the Java virtual machine being monitored.

Returns:

the Java class path.

Throws:

SecurityException - if a security manager exists and its checkPropertiesAccess method doesn't allow access to this system property.

See Also:

SecurityManager.checkPropertyAccess(java.lang.String), System.getProperty(java.lang.String)

getLibraryPath

String getLibraryPath()

Returns the Java library path. This method is equivalent to System.getProperty("java.library.path").

Multiple paths in the Java library path are separated by the path separator character of the platform of the Java virtual machine being monitored.

Returns:

the Java library path.

Throws:

SecurityException - if a security manager exists and its checkPropertiesAccess method doesn't allow access to this system property.

See Also:

SecurityManager.checkPropertyAccess(java.lang.String), System.getProperty(java.lang.String)

isBootClassPathSupported

boolean isBootClassPathSupported()

Tests if the Java virtual machine supports the boot class path mechanism used by the bootstrap class loader to search for class files.

Returns:

true if the Java virtual machine supports the class path mechanism; false otherwise.

getBootClassPath

String getBootClassPath()

Returns the boot class path that is used by the bootstrap class loader to search for class files.

Multiple paths in the boot class path are separated by the path separator character of the platform on which the Java virtual machine is running.

A Java virtual machine implementation may not support the boot class path mechanism for the bootstrap class loader to search for class files. The isBootClassPathSupported() method can be used to determine if the Java virtual machine supports this method.

Returns:

the boot class path.

Throws:

UnsupportedOperationException - if the Java virtual machine does not support this operation.

SecurityException - if a security manager exists and the caller does not have ManagementPermission("monitor").

getInputArguments

List getInputArguments()

Returns the input arguments passed to the Java virtual machine which does not include the arguments to the main method. This method returns an empty list if there is no input argument to the Java virtual machine.

Some Java virtual machine implementations may take input arguments from multiple different sources: for examples, arguments passed from the application that launches the Java virtual machine such as the 'java' command, environment variables, configuration files, etc.

Typically, not all command-line options to the 'java' command are passed to the Java virtual machine. Thus, the returned input arguments may not include all command-line options.

Returns:

a list of String objects; each element is an argument passed to the Java virtual machine.

Throws:

SecurityException - if a security manager exists and the caller does not have ManagementPermission("monitor").

getUptime

long getUptime()

Returns the uptime of the Java virtual machine in milliseconds.

Returns:

uptime of the Java virtual machine in milliseconds.