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

Modifier and Type	Field and Description
public static final int	INVOKE_SINGLE_THREADED Perform method invocation with only the invoking thread resumed

Method Summary

Modifier and Type	Method and Description
public List<InterfaceType>	Returns: a List of `InterfaceType` objects each mirroring an interface of this ClassType in the target VM. If none exist, returns a zero length List. allInterfaces() Gets the interfaces directly and indirectly implemented by this class.
public Method	Returns: the `Method` that matches the given name and signature or `null` if there is no match. concreteMethodByName(String the name of the method to find. name, String the signature of the method to find signature) Returns a single non-abstract `Method` visible from this class that has the given name and signature.
public List<InterfaceType>	Returns: a List of `InterfaceType` objects each mirroring a direct interface this ClassType in the target VM. If none exist, returns a zero length List. interfaces() Gets the interfaces directly implemented by this class.
public Value	Returns: a `Value` mirror of the invoked method's return value. invokeMethod(ThreadReference the thread in which to invoke. thread, Method the `Method` to invoke. method, List<? extends Value> the list of `Value` arguments bound to the invoked method. Values from the list are assigned to arguments in the order they appear in the method signature. arguments, int the integer bit flag options. options) Invokes the specified static `Method` in the target VM.
public boolean	Returns: `true` if this class was declared as an enum; false otherwise. isEnum() Determine if this class was declared as an enum.
public ObjectReference	Returns: an `ObjectReference` mirror of the newly created object. newInstance(ThreadReference the thread in which to invoke. thread, Method the constructor `Method` to invoke. method, List<? extends Value> the list of `Value` arguments bound to the invoked constructor. Values from the list are assigned to arguments in the order they appear in the constructor signature. arguments, int the integer bit flag options. options) Constructs a new instance of this type, using the given constructor `Method` in the target VM.
public void	setValue(Field the field to set. field, Value the value to be assigned. value) Assigns a value to a static field.
public List<ClassType>	Returns: a List of `ClassType` objects each mirroring a loaded subclass of this class in the target VM. If no such classes exist, this method returns a zero-length list. subclasses() Gets the currently loaded, direct subclasses of this class.
public ClassType	Returns: a `ClassType` that mirrors the superclass of this class in the target VM. If no such class exists, returns null superclass() Gets the superclass of this class.

INVOKE_SINGLE_THREADED	back to summary
public static final int INVOKE_SINGLE_THREADED Perform method invocation with only the invoking thread resumed

Method Detail

allInterfaces back to summary

allInterfaces	back to summary
public List<InterfaceType> allInterfaces() Gets the interfaces directly and indirectly implemented by this class. Interfaces returned by `ClassType#interfaces` are returned as well all superinterfaces. Returns:List<InterfaceType> a List of `InterfaceType` objects each mirroring an interface of this ClassType in the target VM. If none exist, returns a zero length List. Exceptions ClassNotPreparedException: if this class not yet been prepared.

public List<InterfaceType> allInterfaces()

Gets the interfaces directly and indirectly implemented by this class. Interfaces returned by ClassType#interfaces are returned as well all superinterfaces.

Returns:List<InterfaceType>

a List of InterfaceType objects each mirroring an interface of this ClassType in the target VM. If none exist, returns a zero length List.

Exceptions

ClassNotPreparedException:: if this class not yet been prepared.

concreteMethodByName back to summary

concreteMethodByName	back to summary
public Method concreteMethodByName(String name, String signature) Returns a single non-abstract `Method` visible from this class that has the given name and signature. See `ReferenceType#methodsByName(java.lang.String, java.lang.String)` for information on signature format. The returned method (if non-null) is a component of `ClassType`. Parameters name:String the name of the method to find. signature:String the signature of the method to find Returns:Method the `Method` that matches the given name and signature or `null` if there is no match. Exceptions ClassNotPreparedException: if methods are not yet available because the class has not yet been prepared. See Also `ReferenceType#visibleMethods`, `ReferenceType#methodsByName(java.lang.String name)`, `ReferenceType#methodsByName(java.lang.String name, java.lang.String signature)`

public Method concreteMethodByName(String name, String signature)

Returns a single non-abstract Method visible from this class that has the given name and signature. See ReferenceType#methodsByName(java.lang.String, java.lang.String) for information on signature format.

The returned method (if non-null) is a component of ClassType.

Parameters

name:String: the name of the method to find.
signature:String: the signature of the method to find

Returns:Method

the Method that matches the given name and signature or null if there is no match.

Exceptions

ClassNotPreparedException:: if methods are not yet available because the class has not yet been prepared.

interfaces back to summary

interfaces	back to summary
public List<InterfaceType> interfaces() Gets the interfaces directly implemented by this class. Only the interfaces that are declared with the "implements" keyword in this class are included. Returns:List<InterfaceType> a List of `InterfaceType` objects each mirroring a direct interface this ClassType in the target VM. If none exist, returns a zero length List. Exceptions ClassNotPreparedException: if this class not yet been prepared.

public List<InterfaceType> interfaces()

Gets the interfaces directly implemented by this class. Only the interfaces that are declared with the "implements" keyword in this class are included.

Returns:List<InterfaceType>

a List of InterfaceType objects each mirroring a direct interface this ClassType in the target VM. If none exist, returns a zero length List.

Exceptions

ClassNotPreparedException:: if this class not yet been prepared.

invokeMethod back to summary

invokeMethod	back to summary
public Value invokeMethod(ThreadReference thread, Method method, List<? extends Value> arguments, int options) throws InvalidTypeException, ClassNotLoadedException, IncompatibleThreadStateException, InvocationException Invokes the specified static `Method` in the target VM. The specified method can be defined in this class, or in a superclass. The method must be a static method but not a static initializer. Use `ClassType#newInstance` to create a new object and run its constructor. The method invocation will occur in the specified thread. Method invocation can occur only if the specified thread has been suspended by an event which occurred in that thread. Method invocation is not supported when the target VM has been suspended through `VirtualMachine#suspend` or when the specified thread is suspended through `ThreadReference#suspend`. The specified method is invoked with the arguments in the specified argument list. The method invocation is synchronous; this method does not return until the invoked method returns in the target VM. If the invoked method throws an exception, this method will throw an `InvocationException` which contains a mirror to the exception object thrown. Object arguments must be assignment compatible with the argument type (This implies that the argument type must be loaded through the enclosing class' class loader). Primitive arguments must be either assignment compatible with the argument type or must be convertible to the argument type without loss of information. If the method being called accepts a variable number of arguments, then the last argument type is an array of some component type. The argument in the matching position can be omitted, or can be null, an array of the same component type, or an argument of the component type followed by any number of other arguments of the same type. If the argument is omitted, then a 0 length array of the component type is passed. The component type can be a primitive type. Autoboxing is not supported. See Section 5.2 of The Java Language Specification for more information on assignment compatibility. By default, all threads in the target VM are resumed while the method is being invoked if they were previously suspended by an event or by `VirtualMachine#suspend` or `ThreadReference#suspend`. This is done to prevent the deadlocks that will occur if any of the threads own resources, such as monitors, that will be needed by the invoked method. Note, however, that this implicit resume acts exactly like `ThreadReference#resume`, so if the thread's suspend count is greater than 1, it will remain in a suspended state during the invocation and thus a deadlock could still occur. By default, when the invocation completes, all threads in the target VM are suspended, regardless their state before the invocation. It is possible that breakpoints or other events might occur during the invocation. This can cause deadlocks as described above. It can also cause a deadlock if invokeMethod is called from the client's event handler thread. In this case, this thread will be waiting for the invokeMethod to complete and won't read the EventSet that comes in for the new event. If this new EventSet is SUSPEND_ALL, then a deadlock will occur because no one will resume the EventSet. To avoid this, all EventRequests should be disabled before doing the invokeMethod, or the invokeMethod should not be done from the client's event handler thread. The resumption of other threads during the invocation can be prevented by specifying the `INVOKE_SINGLE_THREADED` bit flag in the `options` argument; however, there is no protection against or recovery from the deadlocks described above, so this option should be used with great caution. Only the specified thread will be resumed (as described for all threads above). Upon completion of a single threaded invoke, the invoking thread will be suspended once again. Note that any threads started during the single threaded invocation will not be suspended when the invocation completes. If the target VM is disconnected during the invoke (for example, through `VirtualMachine#dispose`) the method invocation continues. API Note Virtual threads are typically user-mode threads scheduled by the Java runtime rather than the operating system. As such, there may be more cases with virtual threads where the `INVOKE_SINGLE_THREADED` option may cause a deadlock. For example, suspending all threads in the target VM may suspend threads that support the timer mechanism for virtual threads, and thus methods such as `Thread#sleep` may deadlock. Parameters thread:ThreadReference the thread in which to invoke. method:Method the `Method` to invoke. arguments:List<? extends Value> the list of `Value` arguments bound to the invoked method. Values from the list are assigned to arguments in the order they appear in the method signature. options:int the integer bit flag options. Returns:Value a `Value` mirror of the invoked method's return value. Exceptions InvalidTypeException: If the arguments do not meet this requirement -- Object arguments must be assignment compatible with the argument type. This implies that the argument type must be loaded through the enclosing class' class loader. Primitive arguments must be either assignment compatible with the argument type or must be convertible to the argument type without loss of information. See JLS section 5.2 for more information on assignment compatibility. ClassNotLoadedException: if any argument type has not yet been loaded through the appropriate class loader. IncompatibleThreadStateException: if the specified thread has not been suspended by an event. InvocationException: if the method invocation resulted in an exception in the target VM. IllegalArgumentException: if the method is not a member of this class or a superclass, if the size of the argument list does not match the number of declared arguments for the method, or if the method is an initializer, constructor or static initializer. VMCannotBeModifiedException: if the VirtualMachine is read-only - see `VirtualMachine#canBeModified()`.

public Value invokeMethod(ThreadReference thread, Method method, List<? extends Value> arguments, int options) throws InvalidTypeException, ClassNotLoadedException, IncompatibleThreadStateException, InvocationException

Invokes the specified static Method in the target VM. The specified method can be defined in this class, or in a superclass. The method must be a static method but not a static initializer. Use ClassType#newInstance to create a new object and run its constructor.

The method invocation will occur in the specified thread. Method invocation can occur only if the specified thread has been suspended by an event which occurred in that thread. Method invocation is not supported when the target VM has been suspended through VirtualMachine#suspend or when the specified thread is suspended through ThreadReference#suspend.

The specified method is invoked with the arguments in the specified argument list. The method invocation is synchronous; this method does not return until the invoked method returns in the target VM. If the invoked method throws an exception, this method will throw an InvocationException which contains a mirror to the exception object thrown.

Object arguments must be assignment compatible with the argument type (This implies that the argument type must be loaded through the enclosing class' class loader). Primitive arguments must be either assignment compatible with the argument type or must be convertible to the argument type without loss of information. If the method being called accepts a variable number of arguments, then the last argument type is an array of some component type. The argument in the matching position can be omitted, or can be null, an array of the same component type, or an argument of the component type followed by any number of other arguments of the same type. If the argument is omitted, then a 0 length array of the component type is passed. The component type can be a primitive type. Autoboxing is not supported. See Section 5.2 of The Java Language Specification for more information on assignment compatibility.

By default, all threads in the target VM are resumed while the method is being invoked if they were previously suspended by an event or by VirtualMachine#suspend or ThreadReference#suspend. This is done to prevent the deadlocks that will occur if any of the threads own resources, such as monitors, that will be needed by the invoked method. Note, however, that this implicit resume acts exactly like ThreadReference#resume, so if the thread's suspend count is greater than 1, it will remain in a suspended state during the invocation and thus a deadlock could still occur. By default, when the invocation completes, all threads in the target VM are suspended, regardless their state before the invocation. It is possible that breakpoints or other events might occur during the invocation. This can cause deadlocks as described above. It can also cause a deadlock if invokeMethod is called from the client's event handler thread. In this case, this thread will be waiting for the invokeMethod to complete and won't read the EventSet that comes in for the new event. If this new EventSet is SUSPEND_ALL, then a deadlock will occur because no one will resume the EventSet. To avoid this, all EventRequests should be disabled before doing the invokeMethod, or the invokeMethod should not be done from the client's event handler thread.

The resumption of other threads during the invocation can be prevented by specifying the INVOKE_SINGLE_THREADED bit flag in the options argument; however, there is no protection against or recovery from the deadlocks described above, so this option should be used with great caution. Only the specified thread will be resumed (as described for all threads above). Upon completion of a single threaded invoke, the invoking thread will be suspended once again. Note that any threads started during the single threaded invocation will not be suspended when the invocation completes.

If the target VM is disconnected during the invoke (for example, through VirtualMachine#dispose) the method invocation continues.

API Note

Virtual threads are typically user-mode threads scheduled by the Java runtime rather than the operating system. As such, there may be more cases with virtual threads where the INVOKE_SINGLE_THREADED option may cause a deadlock. For example, suspending all threads in the target VM may suspend threads that support the timer mechanism for virtual threads, and thus methods such as Thread#sleep may deadlock.

Parameters

thread:ThreadReference: the thread in which to invoke.
method:Method: the Method to invoke.
arguments:List<? extends Value>: the list of Value arguments bound to the invoked method. Values from the list are assigned to arguments in the order they appear in the method signature.
options:int: the integer bit flag options.

Returns:Value

a Value mirror of the invoked method's return value.

Exceptions

InvalidTypeException:: If the arguments do not meet this requirement -- Object arguments must be assignment compatible with the argument type. This implies that the argument type must be loaded through the enclosing class' class loader. Primitive arguments must be either assignment compatible with the argument type or must be convertible to the argument type without loss of information. See JLS section 5.2 for more information on assignment compatibility.
ClassNotLoadedException:: if any argument type has not yet been loaded through the appropriate class loader.
IncompatibleThreadStateException:: if the specified thread has not been suspended by an event.
InvocationException:: if the method invocation resulted in an exception in the target VM.
IllegalArgumentException:: if the method is not a member of this class or a superclass, if the size of the argument list does not match the number of declared arguments for the method, or if the method is an initializer, constructor or static initializer.
VMCannotBeModifiedException:: if the VirtualMachine is read-only - see VirtualMachine#canBeModified().

isEnum back to summary

isEnum	back to summary
public boolean isEnum() Determine if this class was declared as an enum. Returns:boolean `true` if this class was declared as an enum; false otherwise.

public boolean isEnum()

Determine if this class was declared as an enum.

Returns:boolean: true if this class was declared as an enum; false otherwise.

newInstance back to summary

newInstance	back to summary
public ObjectReference newInstance(ThreadReference thread, Method method, List<? extends Value> arguments, int options) throws InvalidTypeException, ClassNotLoadedException, IncompatibleThreadStateException, InvocationException Constructs a new instance of this type, using the given constructor `Method` in the target VM. The specified constructor must be defined in this class. Instance creation will occur in the specified thread. Instance creation can occur only if the specified thread has been suspended by an event which occurred in that thread. Instance creation is not supported when the target VM has been suspended through `VirtualMachine#suspend` or when the specified thread is suspended through `ThreadReference#suspend`. The specified constructor is invoked with the arguments in the specified argument list. The invocation is synchronous; this method does not return until the constructor returns in the target VM. If the invoked method throws an exception, this method will throw an `InvocationException` which contains a mirror to the exception object thrown. Object arguments must be assignment compatible with the argument type (This implies that the argument type must be loaded through the enclosing class' class loader). Primitive arguments must be either assignment compatible with the argument type or must be convertible to the argument type without loss of information. If the method being called accepts a variable number of arguments, then the last argument type is an array of some component type. The argument in the matching position can be omitted, or can be null, an array of the same component type, or an argument of the component type, followed by any number of other arguments of the same type. If the argument is omitted, then a 0 length array of the component type is passed. The component type can be a primitive type. Autoboxing is not supported. See section 5.2 of The Java Language Specification for more information on assignment compatibility. By default, all threads in the target VM are resumed while the method is being invoked if they were previously suspended by an event or by `VirtualMachine#suspend` or `ThreadReference#suspend`. This is done to prevent the deadlocks that will occur if any of the threads own resources, such as monitors, that will be needed by the invoked method. It is possible that breakpoints or other events might occur during the invocation. Note, however, that this implicit resume acts exactly like `ThreadReference#resume`, so if the thread's suspend count is greater than 1, it will remain in a suspended state during the invocation. By default, when the invocation completes, all threads in the target VM are suspended, regardless their state before the invocation. The resumption of other threads during the invocation can be prevented by specifying the `INVOKE_SINGLE_THREADED` bit flag in the `options` argument; however, there is no protection against or recovery from the deadlocks described above, so this option should be used with great caution. Only the specified thread will be resumed (as described for all threads above). Upon completion of a single threaded invoke, the invoking thread will be suspended once again. Note that any threads started during the single threaded invocation will not be suspended when the invocation completes. If the target VM is disconnected during the invoke (for example, through `VirtualMachine#dispose`) the method invocation continues. API Note Virtual threads are typically user-mode threads scheduled by the Java runtime rather than the operating system. As such, there may be more cases with virtual threads where the `INVOKE_SINGLE_THREADED` option may cause a deadlock. For example, suspending all threads in the target VM may suspend threads that support the timer mechanism for virtual threads, and thus methods such as `Thread#sleep` may deadlock. Parameters thread:ThreadReference the thread in which to invoke. method:Method the constructor `Method` to invoke. arguments:List<? extends Value> the list of `Value` arguments bound to the invoked constructor. Values from the list are assigned to arguments in the order they appear in the constructor signature. options:int the integer bit flag options. Returns:ObjectReference an `ObjectReference` mirror of the newly created object. Exceptions InvalidTypeException: If the arguments do not meet this requirement -- Object arguments must be assignment compatible with the argument type. This implies that the argument type must be loaded through the enclosing class' class loader. Primitive arguments must be either assignment compatible with the argument type or must be convertible to the argument type without loss of information. See JLS section 5.2 for more information on assignment compatibility. ClassNotLoadedException: if any argument type has not yet been loaded through the appropriate class loader. IncompatibleThreadStateException: if the specified thread has not been suspended by an event. InvocationException: if the method invocation resulted in an exception in the target VM. IllegalArgumentException: if the method is not a member of this class, if the size of the argument list does not match the number of declared arguments for the constructor, or if the method is not a constructor. VMCannotBeModifiedException: if the VirtualMachine is read-only - see `VirtualMachine#canBeModified()`.

public ObjectReference newInstance(ThreadReference thread, Method method, List<? extends Value> arguments, int options) throws InvalidTypeException, ClassNotLoadedException, IncompatibleThreadStateException, InvocationException

Constructs a new instance of this type, using the given constructor Method in the target VM. The specified constructor must be defined in this class.

Instance creation will occur in the specified thread. Instance creation can occur only if the specified thread has been suspended by an event which occurred in that thread. Instance creation is not supported when the target VM has been suspended through VirtualMachine#suspend or when the specified thread is suspended through ThreadReference#suspend.

The specified constructor is invoked with the arguments in the specified argument list. The invocation is synchronous; this method does not return until the constructor returns in the target VM. If the invoked method throws an exception, this method will throw an InvocationException which contains a mirror to the exception object thrown.

Object arguments must be assignment compatible with the argument type (This implies that the argument type must be loaded through the enclosing class' class loader). Primitive arguments must be either assignment compatible with the argument type or must be convertible to the argument type without loss of information. If the method being called accepts a variable number of arguments, then the last argument type is an array of some component type. The argument in the matching position can be omitted, or can be null, an array of the same component type, or an argument of the component type, followed by any number of other arguments of the same type. If the argument is omitted, then a 0 length array of the component type is passed. The component type can be a primitive type. Autoboxing is not supported. See section 5.2 of The Java Language Specification for more information on assignment compatibility.

If the target VM is disconnected during the invoke (for example, through VirtualMachine#dispose) the method invocation continues.

API Note

Parameters

thread:ThreadReference: the thread in which to invoke.
method:Method: the constructor Method to invoke.
arguments:List<? extends Value>: the list of Value arguments bound to the invoked constructor. Values from the list are assigned to arguments in the order they appear in the constructor signature.
options:int: the integer bit flag options.

Returns:ObjectReference

an ObjectReference mirror of the newly created object.

Exceptions

InvalidTypeException:: If the arguments do not meet this requirement -- Object arguments must be assignment compatible with the argument type. This implies that the argument type must be loaded through the enclosing class' class loader. Primitive arguments must be either assignment compatible with the argument type or must be convertible to the argument type without loss of information. See JLS section 5.2 for more information on assignment compatibility.
ClassNotLoadedException:: if any argument type has not yet been loaded through the appropriate class loader.
IncompatibleThreadStateException:: if the specified thread has not been suspended by an event.
InvocationException:: if the method invocation resulted in an exception in the target VM.
IllegalArgumentException:: if the method is not a member of this class, if the size of the argument list does not match the number of declared arguments for the constructor, or if the method is not a constructor.
VMCannotBeModifiedException:: if the VirtualMachine is read-only - see VirtualMachine#canBeModified().

setValue back to summary

setValue	back to summary
public void setValue(Field field, Value value) throws InvalidTypeException, ClassNotLoadedException Assigns a value to a static field. The `Field` must be valid for this ClassType; that is, it must be from the mirrored object's class or a superclass of that class. The field must not be final. Object values must be assignment compatible with the field type (This implies that the field type must be loaded through the enclosing class' class loader). Primitive values must be either assignment compatible with the field type or must be convertible to the field type without loss of information. See JLS section 5.2 for more information on assignment compatibility. Parameters field:Field the field to set. value:Value the value to be assigned. Exceptions InvalidTypeException: if the value's type does not match the field's declared type. ClassNotLoadedException: if the field type has not yet been loaded through the appropriate class loader. IllegalArgumentException: if the field is not static, the field is final, or the field does not exist in this class. VMCannotBeModifiedException: if the VirtualMachine is read-only - see `VirtualMachine#canBeModified()`.

public void setValue(Field field, Value value) throws InvalidTypeException, ClassNotLoadedException

Assigns a value to a static field. The Field must be valid for this ClassType; that is, it must be from the mirrored object's class or a superclass of that class. The field must not be final.

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

Parameters

field:Field: the field to set.
value:Value: the value to be assigned.

Exceptions

InvalidTypeException:: if the value's type does not match the field's declared type.
ClassNotLoadedException:: if the field type has not yet been loaded through the appropriate class loader.
IllegalArgumentException:: if the field is not static, the field is final, or the field does not exist in this class.
VMCannotBeModifiedException:: if the VirtualMachine is read-only - see VirtualMachine#canBeModified().

subclasses back to summary

subclasses	back to summary
public List<ClassType> subclasses() Gets the currently loaded, direct subclasses of this class. No ordering of this list is guaranteed. Returns:List<ClassType> a List of `ClassType` objects each mirroring a loaded subclass of this class in the target VM. If no such classes exist, this method returns a zero-length list.

public List<ClassType> subclasses()

Gets the currently loaded, direct subclasses of this class. No ordering of this list is guaranteed.

Returns:List<ClassType>: a List of ClassType objects each mirroring a loaded subclass of this class in the target VM. If no such classes exist, this method returns a zero-length list.

superclass back to summary

superclass	back to summary
public ClassType superclass() Gets the superclass of this class. Returns:ClassType a `ClassType` that mirrors the superclass of this class in the target VM. If no such class exists, returns null

public ClassType superclass()

Gets the superclass of this class.

Returns:ClassType: a ClassType that mirrors the superclass of this class in the target VM. If no such class exists, returns null

public Interface ClassType

Field Summary

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Field Detail

Method Detail