Spec-Zone .ru спецификации, руководства, описания, API

com.sun.jdi
Interface VirtualMachine

All Superinterfaces:

Mirror

All Known Subinterfaces:

PathSearchingVirtualMachine

public interface VirtualMachine

extends Mirror

A virtual machine targeted for debugging. More precisely, a mirror representing the composite state of the target VM. All other mirrors are associated with an instance of this interface. Access to all other mirrors is achieved directly or indirectly through an instance of this interface. Access to global VM properties and control of VM execution are supported directly by this interface.

Instances of this interface are created by instances of Connector. Note that a target VM launched by a launching connector is not guaranteed to be stable until after the VMStartEvent has been received.

Any method on VirtualMachine which takes VirtualMachine as an parameter may throw VMDisconnectedException if the target VM is disconnected and the VMDisconnectEvent has been or is available to be read from the EventQueue.

Any method on VirtualMachine which takes VirtualMachine as an parameter may throw VMOutOfMemoryException if the target VM has run out of memory.

Since:

1.3

Field Summary

static int	TRACE_ALL All tracing is enabled.
static int	TRACE_EVENTS Tracing enabled for internal event handling.
static int	TRACE_NONE All tracing is disabled.
static int	TRACE_OBJREFS Tracing enabled for internal management of object references.
static int	TRACE_RECEIVES Tracing enabled for JDWP packets received from target VM.
static int	TRACE_REFTYPES Tracing enabled for internal managment of reference types.
static int	TRACE_SENDS Tracing enabled for JDWP packets sent to target VM.

Method Summary

List	allClasses() Returns all loaded types.
List	allThreads() Returns a list of the currently running threads.
boolean	canAddMethod() Determines if the target VM supports the addition of methods when performing class redefinition.
boolean	canGetBytecodes() Determines if the target VM supports the retrieval of a method's bytecodes.
boolean	canGetCurrentContendedMonitor() Determines if the target VM supports the retrieval of the monitor for which a thread is currently waiting.
boolean	canGetMonitorInfo() Determines if the target VM supports the retrieval of the monitor information for an object.
boolean	canGetOwnedMonitorInfo() Determines if the target VM supports the retrieval of the monitors owned by a thread.
boolean	canGetSourceDebugExtension() Determines if the target VM supports getting the source debug extension.
boolean	canGetSyntheticAttribute() Determines if the target VM supports the query of the synthetic attribute of a method or field.
boolean	canPopFrames() Determines if the target VM supports popping frames of a threads stack.
boolean	canRedefineClasses() Determines if the target VM supports any level of class redefinition.
boolean	canRequestVMDeathEvent() Determines if the target VM supports the creation of VMDeathRequests.
boolean	canUnrestrictedlyRedefineClasses() Determines if the target VM supports unrestricted changes when performing class redefinition.
boolean	canUseInstanceFilters() Determines if the target VM supports filtering events by specific instance object.
boolean	canWatchFieldAccess() Determines if the target VM supports watchpoints for field access.
boolean	canWatchFieldModification() Determines if the target VM supports watchpoints for field modification.
List	classesByName(String className) Returns the loaded reference types that match a given name.
String	description() Returns text information on the target VM and the debugger support that mirrors it.
void	dispose() Invalidates this virtual machine mirror.
EventQueue	eventQueue() Returns the event queue for this virtual machine.
EventRequestManager	eventRequestManager() Returns the event request manager for this virtual machine.
void	exit(int exitCode) Causes the mirrored VM to terminate with the given error code.
String	getDefaultStratum() Return this VM's default stratum.
BooleanValue	mirrorOf(boolean value) Creates a BooleanValue for the given value.
ByteValue	mirrorOf(byte value) Creates a ByteValue for the given value.
CharValue	mirrorOf(char value) Creates a CharValue for the given value.
DoubleValue	mirrorOf(double value) Creates a DoubleValue for the given value.
FloatValue	mirrorOf(float value) Creates a FloatValue for the given value.
IntegerValue	mirrorOf(int value) Creates an IntegerValue for the given value.
LongValue	mirrorOf(long value) Creates a LongValue for the given value.
ShortValue	mirrorOf(short value) Creates a ShortValue for the given value.
StringReference	mirrorOf(String value) Creates a string in this virtual machine.
String	name() Returns the name of the target VM as reported by the property java.vm.name.
Process	process() Returns the Process object for this virtual machine if launched by a LaunchingConnector
void	redefineClasses(Map classToBytes) All classes given are redefined according to the definitions supplied.
void	resume() Continues the execution of the application running in this virtual machine.
void	setDebugTraceMode(int traceFlags) Traces the activities performed by the com.sun.jdi implementation.
void	setDefaultStratum(String stratum) Set this VM's default stratum (see Location for a discussion of strata).
void	suspend() Suspends the execution of the application running in this virtual machine.
List	topLevelThreadGroups() Returns each thread group which does not have a parent.
String	version() Returns the version of the Java Runtime Environment in the target VM as reported by the property java.version.

Methods inherited from interface com.sun.jdi.Mirror

toString, virtualMachine

Field Detail

TRACE_NONE

public static final int TRACE_NONE

All tracing is disabled.

See Also:

Constant Field Values

TRACE_SENDS

public static final int TRACE_SENDS

Tracing enabled for JDWP packets sent to target VM.

See Also:

Constant Field Values

TRACE_RECEIVES

public static final int TRACE_RECEIVES

Tracing enabled for JDWP packets received from target VM.

See Also:

Constant Field Values

TRACE_EVENTS

public static final int TRACE_EVENTS

Tracing enabled for internal event handling.

See Also:

Constant Field Values

TRACE_REFTYPES

public static final int TRACE_REFTYPES

Tracing enabled for internal managment of reference types.

See Also:

Constant Field Values

TRACE_OBJREFS

public static final int TRACE_OBJREFS

Tracing enabled for internal management of object references.

See Also:

Constant Field Values

TRACE_ALL

public static final int TRACE_ALL

All tracing is enabled.

See Also:

Constant Field Values

Method Detail

classesByName

public List classesByName(String className)

Returns the loaded reference types that match a given name. The name must be fully qualified (for example, java.lang.String). The returned list will contain a ReferenceType for each class or interface found with the given name. The search is confined to loaded classes only; no attempt is made to load a class of the given name.

The returned list will include reference types loaded at least to the point of preparation and types (like array) for which preparation is not defined.

Parameters:

className - the class/interface name to search for

Returns:

a list of ReferenceType objects, each mirroring a type in the target VM with the given name.

allClasses

public List allClasses()

Returns all loaded types. For each loaded type in the target VM a ReferenceType will be placed in the returned list. The list will include ReferenceTypes which mirror classes, interfaces, and array types.

The returned list will include reference types loaded at least to the point of preparation and types (like array) for which preparation is not defined.

Returns:

a list of ReferenceType objects, each mirroring a loaded type in the target VM.

redefineClasses

public void redefineClasses(Map classToBytes)

All classes given are redefined according to the definitions supplied. If any redefined methods have active stack frames, those active frames continue to run the bytecodes of the previous method. The redefined methods will be used on new invokes. If resetting these frames is desired, use ThreadReference.popFrames(StackFrame) with Method.isObsolete().

This function does not cause any initialization except that which would occur under the customary JVM semantics. In other words, redefining a class does not cause its initializers to be run. The values of preexisting static variables will remain as they were prior to the call. However, completely uninitialized (new) static variables will be assigned their default value.

If a redefined class has instances then all those instances will have the fields defined by the redefined class at the completion of the call. Preexisting fields will retain their previous values. Any new fields will have their default values; no instance initializers or constructors are run.

Threads need not be suspended.

No events are generated by this function.

All breakpoints in the redefined classes are deleted.

Not all target virtual machines support this operation. Use canRedefineClasses() to determine if the operation is supported. Use canAddMethod() to determine if the redefinition can add methods. Use canUnrestrictedlyRedefineClasses() to determine if the redefinition can change the schema, delete methods, change the class hierarchy, etc.

Parameters:

classToBytes - A map from ReferenceType to array of byte. The bytes represent the new class definition and are in Java Virtual Machine class file format.

Throws:

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

• If canRedefineClasses() is false any call of this method will throw this exception.
• If canAddMethod() is false attempting to add a method will throw this exception.
• If canUnrestrictedlyRedefineClasses() is false, attempting any of the following will throw this exception
  • changing the schema (the fields)
  • changing the hierarchy (subclasses, interfaces)
  • deleting a method
  • changing class modifiers
  • changing method modifiers

NoClassDefFoundError - if the bytes don't correspond to the reference type (the names don't match).

VerifyError - if a "verifier" detects that a class, though well formed, contains an internal inconsistency or security problem.

ClassFormatError - if the bytes do not represent a valid class.

ClassCircularityError - if a circularity has been detected while initializing a class.

UnsupportedClassVersionError - if the major and minor version numbers in bytes are not supported by the VM.

Since:

1.4

See Also:

Method.isObsolete(), ThreadReference.popFrames(com.sun.jdi.StackFrame), canRedefineClasses(), canAddMethod(), canUnrestrictedlyRedefineClasses()

allThreads

public List allThreads()

Returns a list of the currently running threads. For each running thread in the target VM, a ThreadReference that mirrors it is placed in the list. The returned list contains threads created through java.lang.Thread, all native threads attached to the target VM through JNI, and system threads created by the target VM. Thread objects that have not yet been started (see Thread.start()) and thread objects that have completed their execution are not included in the returned list.

Returns:

a list of ThreadReference objects, one for each running thread in the mirrored VM.

suspend

public void suspend()

Suspends the execution of the application running in this virtual machine. All threads currently running will be suspended.

Unlike Thread.suspend(), suspends of both the virtual machine and individual threads are counted. Before a thread will run again, it must be resumed (through resume() or ThreadReference.resume()) the same number of times it has been suspended.

resume

public void resume()

Continues the execution of the application running in this virtual machine. All threads are resumed as documented in ThreadReference.resume().

See Also:

suspend()

topLevelThreadGroups

public List topLevelThreadGroups()

Returns each thread group which does not have a parent. For each top level thread group a ThreadGroupReference is placed in the returned list.

This command may be used as the first step in building a tree (or trees) of the existing thread groups.

Returns:

a list of ThreadGroupReference objects, one for each top level thread group.

eventQueue

public EventQueue eventQueue()

Returns the event queue for this virtual machine. A virtual machine has only one EventQueue object, this method will return the same instance each time it is invoked.

Returns:

the EventQueue for this virtual machine.

eventRequestManager

public EventRequestManager eventRequestManager()

Returns the event request manager for this virtual machine. The EventRequestManager controls user settable events such as breakpoints. A virtual machine has only one EventRequestManager object, this method will return the same instance each time it is invoked.

Returns:

the EventRequestManager for this virtual machine.

mirrorOf

public BooleanValue mirrorOf(boolean value)

Creates a BooleanValue for the given value. This value can be used for setting and comparing against a value retrieved from a variable or field in this virtual machine.

Parameters:

value - a boolean for which to create the value

Returns:

the BooleanValue for the given boolean.

mirrorOf

public ByteValue mirrorOf(byte value)

Creates a ByteValue for the given value. This value can be used for setting and comparing against a value retrieved from a variable or field in this virtual machine.

Parameters:

value - a byte for which to create the value

Returns:

the ByteValue for the given byte.

mirrorOf

public CharValue mirrorOf(char value)

Creates a CharValue for the given value. This value can be used for setting and comparing against a value retrieved from a variable or field in this virtual machine.

Parameters:

value - a char for which to create the value

Returns:

the CharValue for the given char.

mirrorOf

public ShortValue mirrorOf(short value)

Creates a ShortValue for the given value. This value can be used for setting and comparing against a value retrieved from a variable or field in this virtual machine.

Parameters:

value - a short for which to create the value

Returns:

the ShortValue for the given short.

mirrorOf

public IntegerValue mirrorOf(int value)

Creates an IntegerValue for the given value. This value can be used for setting and comparing against a value retrieved from a variable or field in this virtual machine.

Parameters:

value - an int for which to create the value

Returns:

the IntegerValue for the given int.

mirrorOf

public LongValue mirrorOf(long value)

Creates a LongValue for the given value. This value can be used for setting and comparing against a value retrieved from a variable or field in this virtual machine.

Parameters:

value - a long for which to create the value

Returns:

the LongValue for the given long.

mirrorOf

public FloatValue mirrorOf(float value)

Creates a FloatValue for the given value. This value can be used for setting and comparing against a value retrieved from a variable or field in this virtual machine.

Parameters:

value - a float for which to create the value

Returns:

the FloatValue for the given float.

mirrorOf

public DoubleValue mirrorOf(double value)

Creates a DoubleValue for the given value. This value can be used for setting and comparing against a value retrieved from a variable or field in this virtual machine.

Parameters:

value - a double for which to create the value

Returns:

the DoubleValue for the given double.

mirrorOf

public StringReference mirrorOf(String value)

Creates a string in this virtual machine. The created string can be used for setting and comparing against a string value retrieved from a variable or field in this virtual machine.

Parameters:

value - the string to be created

Returns:

a StringReference that mirrors the newly created string in the target VM.

process

public Process process()

Returns the Process object for this virtual machine if launched by a LaunchingConnector

Returns:

the Process object for this virtual machine, or null if it was not launched by a LaunchingConnector.

dispose

public void dispose()

Invalidates this virtual machine mirror. The communication channel to the target VM is closed, and the target VM prepares to accept another subsequent connection from this debugger or another debugger, including the following tasks:

• All event requests are cancelled.
• All threads suspended by suspend() or by ThreadReference.suspend() are resumed as many times as necessary for them to run.
• Garbage collection is re-enabled in all cases where it was disabled through ObjectReference.disableCollection().

Any current method invocations executing in the target VM are continued after the disconnection. Upon completion of any such method invocation, the invoking thread continues from the location where it was originally stopped.

Resources originating in this VirtualMachine (ObjectReferences, ReferenceTypes, etc.) will become invalid.

exit

public void exit(int exitCode)

Causes the mirrored VM to terminate with the given error code. All resources associated with this VirtualMachine are freed. If the mirrored VM is remote, the communication channel to it will be closed. Resources originating in this VirtualMachine (ObjectReferences, ReferenceTypes, etc.) will become invalid.

Threads running in the mirrored VM are abruptly terminated. A thread death exception is not thrown and finally blocks are not run.

Parameters:

exitCode - the exit code for the target VM. On some platforms, the exit code might be truncated, for example, to the lower order 8 bits.

canWatchFieldModification

public boolean canWatchFieldModification()

Determines if the target VM supports watchpoints for field modification.

Returns:

true if the feature is supported, false otherwise.

canWatchFieldAccess

public boolean canWatchFieldAccess()

Determines if the target VM supports watchpoints for field access.

Returns:

true if the feature is supported, false otherwise.

canGetBytecodes

public boolean canGetBytecodes()

Determines if the target VM supports the retrieval of a method's bytecodes.

Returns:

true if the feature is supported, false otherwise.

canGetSyntheticAttribute

public boolean canGetSyntheticAttribute()

Determines if the target VM supports the query of the synthetic attribute of a method or field.

Returns:

true if the feature is supported, false otherwise.

canGetOwnedMonitorInfo

public boolean canGetOwnedMonitorInfo()

Determines if the target VM supports the retrieval of the monitors owned by a thread.

Returns:

true if the feature is supported, false otherwise.

canGetCurrentContendedMonitor

public boolean canGetCurrentContendedMonitor()

Determines if the target VM supports the retrieval of the monitor for which a thread is currently waiting.

Returns:

true if the feature is supported, false otherwise.

canGetMonitorInfo

public boolean canGetMonitorInfo()

Determines if the target VM supports the retrieval of the monitor information for an object.

Returns:

true if the feature is supported, false otherwise.

canUseInstanceFilters

public boolean canUseInstanceFilters()

Determines if the target VM supports filtering events by specific instance object. For example, see BreakpointRequest.addInstanceFilter(com.sun.jdi.ObjectReference).

Returns:

true if the feature is supported, false otherwise.

canRedefineClasses

public boolean canRedefineClasses()

Determines if the target VM supports any level of class redefinition.

Returns:

true if the feature is supported, false otherwise.

Since:

1.4

See Also:

redefineClasses(java.util.Map)

canAddMethod

public boolean canAddMethod()

Determines if the target VM supports the addition of methods when performing class redefinition.

Returns:

true if the feature is supported, false otherwise.

Since:

1.4

See Also:

redefineClasses(java.util.Map)

canUnrestrictedlyRedefineClasses

public boolean canUnrestrictedlyRedefineClasses()

Determines if the target VM supports unrestricted changes when performing class redefinition.

Returns:

true if the feature is supported, false otherwise.

Since:

1.4

See Also:

redefineClasses(java.util.Map)

canPopFrames

public boolean canPopFrames()

Determines if the target VM supports popping frames of a threads stack.

Returns:

true if the feature is supported, false otherwise.

Since:

1.4

See Also:

ThreadReference.popFrames(com.sun.jdi.StackFrame)

canGetSourceDebugExtension

public boolean canGetSourceDebugExtension()

Determines if the target VM supports getting the source debug extension.

Returns:

true if the feature is supported, false otherwise.

Since:

1.4

See Also:

ReferenceType.sourceDebugExtension()

canRequestVMDeathEvent

public boolean canRequestVMDeathEvent()

Determines if the target VM supports the creation of VMDeathRequests.

Returns:

true if the feature is supported, false otherwise.

Since:

1.4

See Also:

EventRequestManager.createVMDeathRequest()

setDefaultStratum

public void setDefaultStratum(String stratum)

Set this VM's default stratum (see Location for a discussion of strata). Overrides the per-class default set in the class file.

Affects location queries (such as, Location.sourceName()) and the line boundaries used in single stepping.

Parameters:

stratum - the stratum to set as VM default, or null to use per-class defaults.

Throws:

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

Since:

1.4

getDefaultStratum

public String getDefaultStratum()

Return this VM's default stratum.

Returns:

null (meaning that the per-class default - ReferenceType.defaultStratum() - should be used) unless the default stratum has been set with setDefaultStratum(String).

Since:

1.4

See Also:

setDefaultStratum(String), ReferenceType.defaultStratum()

description

public String description()

Returns text information on the target VM and the debugger support that mirrors it. No specific format for this information is guaranteed. Typically, this string contains version information for the target VM and debugger interfaces. More precise information on VM and JDI versions is available through version(), VirtualMachineManager.majorInterfaceVersion(), and VirtualMachineManager.minorInterfaceVersion()

Returns:

the description.

version

public String version()

Returns the version of the Java Runtime Environment in the target VM as reported by the property java.version. For obtaining the JDI interface version, use VirtualMachineManager.majorInterfaceVersion() and VirtualMachineManager.minorInterfaceVersion()

Returns:

the target VM version.

name

public String name()

Returns the name of the target VM as reported by the property java.vm.name.

Returns:

the target VM name.

setDebugTraceMode

public void setDebugTraceMode(int traceFlags)

Traces the activities performed by the com.sun.jdi implementation. All trace information is output to System.err. The given trace flags are used to limit the output to only the information desired. The given flags are in effect and the corresponding trace will continue until the next call to this method.

Output is implementation dependent and trace mode may be ignored.

Parameters:

traceFlags - identifies which kinds of tracing to enable.