OpenJDK 27 · com.sun.jdi.StackFrame · APIdia, the JavaDoc alternative

Method Summary

Modifier and Type	Method and Description
public List<Value>	Returns: a list containing a `Value` object for each argument to this frame, in the order in which the arguments were declared. If the method corresponding to this frame has no arguments, an empty list is returned. getArgumentValues() Returns the values of all arguments in this frame.
public Value	Returns: the `Value` of the instance field. getValue(LocalVariable the `LocalVariable` to be accessed variable) Gets the `Value` of a `LocalVariable` in this frame.
public Map<LocalVariable, Value>	Returns: a map associating each `LocalVariable` with its `Value` getValues(List<? extends LocalVariable> a list of `LocalVariable` objects to be accessed variables) Returns the values of multiple local variables in this frame.
public Location	Returns: the `Location` of the current instruction. location() Redeclares com.sun.jdi.Locatable.location. Returns the `Location` of the current instruction in the frame.
public void	setValue(LocalVariable the field containing the requested value variable, Value the new value to assign value) Sets the `Value` of a `LocalVariable` in this frame.
public ObjectReference	Returns: an `ObjectReference`, or null if the frame represents a native or static method. thisObject() Returns the value of 'this' for the current frame.
public ThreadReference	Returns: a `ThreadReference` which mirrors the frame's thread. thread() Returns the thread under which this frame's method is running.
public LocalVariable	Returns: the matching `LocalVariable`, or null if there is no visible variable with the given name; frames in native methods will always return null. visibleVariableByName(String the variable name to find name) Finds a `LocalVariable` that matches the given name and is visible at the current frame location.
public List<LocalVariable>	Returns: the list of `LocalVariable` objects currently visible; the list will be empty if there are no visible variables; specifically, frames in native methods will always return a zero-length list. visibleVariables() Returns a list containing each `LocalVariable` that can be accessed from this frame's location.

Inherited from com.sun.jdi.Mirror:: toString virtualMachine

Method Detail

getArgumentValues back to summary

getArgumentValues	back to summary
public List<Value> getArgumentValues() Returns the values of all arguments in this frame. Values are returned even if no local variable information is present. Returns:List<Value> a list containing a `Value` object for each argument to this frame, in the order in which the arguments were declared. If the method corresponding to this frame has no arguments, an empty list is returned. Exceptions InvalidStackFrameException: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid. Since 1.6

public List<Value> getArgumentValues()

Returns the values of all arguments in this frame. Values are returned even if no local variable information is present.

Returns:List<Value>

a list containing a Value object for each argument to this frame, in the order in which the arguments were declared. If the method corresponding to this frame has no arguments, an empty list is returned.

Exceptions

InvalidStackFrameException:: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid.

Since

1.6

getValue back to summary

getValue	back to summary
public Value getValue(LocalVariable variable) Gets the `Value` of a `LocalVariable` in this frame. The variable must be valid for this frame's method and visible according to the rules described in `visibleVariables`. Parameters variable:LocalVariable the `LocalVariable` to be accessed Returns:Value the `Value` of the instance field. Exceptions IllegalArgumentException: if the variable is either invalid for this frame's method or not visible. InvalidStackFrameException: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid.

public Value getValue(LocalVariable variable)

Gets the Value of a LocalVariable in this frame. The variable must be valid for this frame's method and visible according to the rules described in visibleVariables.

Parameters

variable:LocalVariable: the LocalVariable to be accessed

Returns:Value

the Value of the instance field.

Exceptions

IllegalArgumentException:: if the variable is either invalid for this frame's method or not visible.
InvalidStackFrameException:: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid.

getValues back to summary

getValues	back to summary
public Map<LocalVariable, Value> getValues(List<? extends LocalVariable> variables) Returns the values of multiple local variables in this frame. Each variable must be valid for this frame's method and visible according to the rules described in `visibleVariables`. Parameters variables:List<? extends LocalVariable> a list of `LocalVariable` objects to be accessed Returns:Map<LocalVariable, Value> a map associating each `LocalVariable` with its `Value` Exceptions IllegalArgumentException: if any variable is either invalid for this frame's method or not visible. InvalidStackFrameException: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid.

public Map<LocalVariable, Value> getValues(List<? extends LocalVariable> variables)

Returns the values of multiple local variables in this frame. Each variable must be valid for this frame's method and visible according to the rules described in visibleVariables.

Parameters

variables:List<? extends LocalVariable>: a list of LocalVariable objects to be accessed

Returns:Map<LocalVariable, Value>

a map associating each LocalVariable with its Value

Exceptions

IllegalArgumentException:: if any variable is either invalid for this frame's method or not visible.
InvalidStackFrameException:: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid.

location back to summary

location	back to summary
public Location location() Redeclares com.sun.jdi.Locatable.location. Returns the `Location` of the current instruction in the frame. The method for which this frame was created can also be accessed through the returned location. For the top frame in the stack, this location identifies the next instruction to be executed. For all other frames, this location identifies the instruction that caused the next frame's method to be invoked. If the frame represents a native method invocation, the returned location indicates the class and method, but the code index will not be valid (-1). Returns:Location the `Location` of the current instruction. Exceptions InvalidStackFrameException: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid.

public Location location()

Redeclares com.sun.jdi.Locatable.location.

Returns the Location of the current instruction in the frame. The method for which this frame was created can also be accessed through the returned location. For the top frame in the stack, this location identifies the next instruction to be executed. For all other frames, this location identifies the instruction that caused the next frame's method to be invoked. If the frame represents a native method invocation, the returned location indicates the class and method, but the code index will not be valid (-1).

Returns:Location

the Location of the current instruction.

Exceptions

InvalidStackFrameException:: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid.

setValue back to summary

setValue	back to summary
public void setValue(LocalVariable variable, Value value) throws InvalidTypeException, ClassNotLoadedException Sets the `Value` of a `LocalVariable` in this frame. The variable must be valid for this frame's method and visible according to the rules described in `visibleVariables`. In the case of virtual threads, the target VM supports setting values of local variables when this frame is the topmost frame and the thread is suspended at an event. The target VM may support setting local variables in other cases. Object values must be assignment compatible with the variable type (This implies that the variable type must be loaded through the enclosing class's class loader). Primitive values must be either assignment compatible with the variable type or must be convertible to the variable type without loss of information. See JLS section 5.2 for more information on assignment compatibility. Parameters variable:LocalVariable the field containing the requested value value:Value the new value to assign Exceptions InvalidTypeException: if the value's type does not match the variable's type. ClassNotLoadedException: if the variable type has not yet been loaded through the appropriate class loader. IllegalArgumentException: if the field is not valid for this object's class. InvalidStackFrameException: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid. OpaqueFrameException: if this frame is on the call stack of a suspended virtual thread, and the target VM does not support setting the value of local variables in this frame. VMCannotBeModifiedException: if the VirtualMachine is read-only. See Also `VirtualMachine#canBeModified()`

public void setValue(LocalVariable variable, Value value) throws InvalidTypeException, ClassNotLoadedException

Sets the Value of a LocalVariable in this frame. The variable must be valid for this frame's method and visible according to the rules described in visibleVariables.

In the case of virtual threads, the target VM supports setting values of local variables when this frame is the topmost frame and the thread is suspended at an event. The target VM may support setting local variables in other cases.

Object values must be assignment compatible with the variable type (This implies that the variable type must be loaded through the enclosing class's class loader). Primitive values must be either assignment compatible with the variable type or must be convertible to the variable type without loss of information. See JLS section 5.2 for more information on assignment compatibility.

Parameters

variable:LocalVariable: the field containing the requested value
value:Value: the new value to assign

Exceptions

InvalidTypeException:: if the value's type does not match the variable's type.
ClassNotLoadedException:: if the variable type has not yet been loaded through the appropriate class loader.
IllegalArgumentException:: if the field is not valid for this object's class.
InvalidStackFrameException:: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid.
OpaqueFrameException:: if this frame is on the call stack of a suspended virtual thread, and the target VM does not support setting the value of local variables in this frame.
VMCannotBeModifiedException:: if the VirtualMachine is read-only.

See Also

VirtualMachine#canBeModified()

thisObject back to summary

thisObject	back to summary
public ObjectReference thisObject() Returns the value of 'this' for the current frame. The `ObjectReference` for 'this' is only available for non-native instance methods. Returns:ObjectReference an `ObjectReference`, or null if the frame represents a native or static method. Exceptions InvalidStackFrameException: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid.

public ObjectReference thisObject()

Returns the value of 'this' for the current frame. The ObjectReference for 'this' is only available for non-native instance methods.

Returns:ObjectReference

an ObjectReference, or null if the frame represents a native or static method.

Exceptions

InvalidStackFrameException:: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid.

thread back to summary

thread	back to summary
public ThreadReference thread() Returns the thread under which this frame's method is running. Returns:ThreadReference a `ThreadReference` which mirrors the frame's thread. Exceptions InvalidStackFrameException: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid.

public ThreadReference thread()

Returns the thread under which this frame's method is running.

Returns:ThreadReference

a ThreadReference which mirrors the frame's thread.

Exceptions

InvalidStackFrameException:: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid.

visibleVariableByName back to summary

visibleVariableByName	back to summary
public LocalVariable visibleVariableByName(String name) throws AbsentInformationException Finds a `LocalVariable` that matches the given name and is visible at the current frame location. See `visibleVariables` for more information on visibility. Parameters name:String the variable name to find Returns:LocalVariable the matching `LocalVariable`, or null if there is no visible variable with the given name; frames in native methods will always return null. Exceptions AbsentInformationException: if there is no local variable information for this method. InvalidStackFrameException: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid. NativeMethodException: if the current method is native.

public LocalVariable visibleVariableByName(String name) throws AbsentInformationException

Finds a LocalVariable that matches the given name and is visible at the current frame location. See visibleVariables for more information on visibility.

Parameters

name:String: the variable name to find

Returns:LocalVariable

the matching LocalVariable, or null if there is no visible variable with the given name; frames in native methods will always return null.

Exceptions

AbsentInformationException:: if there is no local variable information for this method.
InvalidStackFrameException:: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid.
NativeMethodException:: if the current method is native.

visibleVariables back to summary

visibleVariables	back to summary
public List<LocalVariable> visibleVariables() throws AbsentInformationException Returns a list containing each `LocalVariable` that can be accessed from this frame's location. Visibility is based on the code index of the current instruction of this StackFrame. Each variable has a range of byte code indices in which it is accessible. If this stack frame's method matches this variable's method and if the code index of this StackFrame is within the variable's byte code range, the variable is visible. A variable's byte code range is at least as large as the scope of that variable, but can continue beyond the end of the scope under certain circumstances: the compiler/VM does not immediately reuse the variable's slot. the compiler/VM is implemented to report the extended range that would result from the item above. The advantage of an extended range is that variables from recently exited scopes may remain available for examination (this is especially useful for loop indices). If, as a result of the extensions above, the current frame location is contained within the range of multiple local variables of the same name, the variable with the highest-starting range is chosen for the returned list. Returns:List<LocalVariable> the list of `LocalVariable` objects currently visible; the list will be empty if there are no visible variables; specifically, frames in native methods will always return a zero-length list. Exceptions AbsentInformationException: if there is no local variable information for this method. InvalidStackFrameException: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid. NativeMethodException: if the current method is native.

public List<LocalVariable> visibleVariables() throws AbsentInformationException

Returns a list containing each LocalVariable that can be accessed from this frame's location.

Visibility is based on the code index of the current instruction of this StackFrame. Each variable has a range of byte code indices in which it is accessible. If this stack frame's method matches this variable's method and if the code index of this StackFrame is within the variable's byte code range, the variable is visible.

A variable's byte code range is at least as large as the scope of that variable, but can continue beyond the end of the scope under certain circumstances:

the compiler/VM does not immediately reuse the variable's slot.
the compiler/VM is implemented to report the extended range that would result from the item above.

The advantage of an extended range is that variables from recently exited scopes may remain available for examination (this is especially useful for loop indices). If, as a result of the extensions above, the current frame location is contained within the range of multiple local variables of the same name, the variable with the highest-starting range is chosen for the returned list.

Returns:List<LocalVariable>

the list of LocalVariable objects currently visible; the list will be empty if there are no visible variables; specifically, frames in native methods will always return a zero-length list.

Exceptions

AbsentInformationException:: if there is no local variable information for this method.
InvalidStackFrameException:: if this stack frame has become invalid. Once the frame's thread is resumed, the stack frame is no longer valid.
NativeMethodException:: if the current method is native.

public Interface StackFrame

Method Summary

Method Detail