Class JdiExecutionControl

java.lang.Object

jdk.jshell.execution.StreamingExecutionControl

jdk.jshell.execution.JdiExecutionControl

All Implemented Interfaces:: AutoCloseable, ExecutionControl

Direct Known Subclasses:: JdiDefaultExecutionControl

public abstract class JdiExecutionControl extends StreamingExecutionControl implements ExecutionControl

Abstract JDI implementation of ExecutionControl.

Since:: 9

Nested Class Summary

Nested classes/interfaces declared in interface ExecutionControl

ExecutionControl.ClassBytecodes, ExecutionControl.ClassInstallException, ExecutionControl.EngineTerminationException, ExecutionControl.ExecutionControlException, ExecutionControl.InternalException, ExecutionControl.NotImplementedException, ExecutionControl.ResolutionException, ExecutionControl.RunException, ExecutionControl.StoppedException, ExecutionControl.UserException

Modifier and Type	Interface	Description
`static final class`	`ExecutionControl.ClassBytecodes`	Bundles class name with class bytecodes.
`static class`	`ExecutionControl.ClassInstallException`	A class install (load or redefine) encountered a problem.
`static class`	`ExecutionControl.EngineTerminationException`	Unbidden execution engine termination has occurred.
`static class`	`ExecutionControl.ExecutionControlException`	The abstract base of all `ExecutionControl` exceptions.
`static class`	`ExecutionControl.InternalException`	An internal problem has occurred.
`static class`	`ExecutionControl.NotImplementedException`	The command is not implemented.
`static class`	`ExecutionControl.ResolutionException`	An exception indicating that a `DeclarationSnippet` with unresolved references has been encountered.
`static class`	`ExecutionControl.RunException`	The abstract base of of exceptions specific to running user code.
`static class`	`ExecutionControl.StoppedException`	An exception indicating that an `ExecutionControl.invoke(java.lang.String, java.lang.String)` (or theoretically a `ExecutionControl.varValue(java.lang.String, java.lang.String)`) has been interrupted by a `ExecutionControl.stop()`.
`static class`	`ExecutionControl.UserException`	A 'normal' user exception occurred.

Constructor Summary

JdiExecutionControl(ObjectOutput out,
 ObjectInput in)

Modifier	Constructor	Description
`protected`	Create an instance.

Method Summary

Modifier and Type	Method	Description
`void`	`redefine(ExecutionControl.ClassBytecodes[] cbcs)`	Redefine the specified classes.
`protected ReferenceType`	`referenceType(VirtualMachine vm, String name)`	Returns the JDI `ReferenceType` corresponding to the specified class name.
`protected abstract VirtualMachine`	`vm()`	Returns the JDI `VirtualMachine` instance.

Methods declared in class StreamingExecutionControl

addToClasspath, close, extensionCommand, invoke, load, stop, varValue

Modifier and Type	Method	Description
`void`	`addToClasspath(String path)`	Adds the path to the execution class path.
`void`	`close()`	Closes the execution engine.
`Object`	`extensionCommand(String command, Object arg)`	Run a non-standard command (or a standard command from a newer version).
`String`	`invoke(String classname, String methodname)`	Invokes an executable Snippet by calling a method on the specified wrapper class.
`void`	`load(ExecutionControl.ClassBytecodes[] cbcs)`	Attempts to load new classes.
`void`	`stop()`	Interrupts a running invoke.
`String`	`varValue(String classname, String varname)`	Returns the value of a variable.

Methods declared in class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Modifier and Type	Method	Description
`protected Object`	`clone()`	Creates and returns a copy of this object.
`boolean`	`equals(Object obj)`	Indicates whether some other object is "equal to" this one.
`protected void`	`finalize()`	Deprecated, for removal: This API element is subject to removal in a future version. Finalization is deprecated and subject to removal in a future release.
`final Class<?>`	`getClass()`	Returns the runtime class of this `Object`.
`int`	`hashCode()`	Returns a hash code value for this object.
`final void`	`notify()`	Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()`	Wakes up all threads that are waiting on this object's monitor.
`String`	`toString()`	Returns a string representation of the object.
`final void`	`wait()`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
`final void`	`wait(long timeoutMillis)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis, int nanos)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

Constructor Details

JdiExecutionControl

protected JdiExecutionControl(ObjectOutput out, ObjectInput in)

Create an instance.

Parameters:: out - the output from the remote agent; in - the input to the remote agent

Method Details

vm

protected abstract VirtualMachine vm() throws ExecutionControl.EngineTerminationException

Returns the JDI VirtualMachine instance.

Returns:: the virtual machine
Throws:: ExecutionControl.EngineTerminationException - if the VM is dead/disconnected

redefine

public void redefine(ExecutionControl.ClassBytecodes[] cbcs) throws ExecutionControl.ClassInstallException, ExecutionControl.EngineTerminationException

Redefine the specified classes. Where 'redefine' is, as in JDI and JVMTI, an in-place replacement of the classes (preserving class identity) -- that is, existing references to the class do not need to be recompiled. This implementation uses JDI VirtualMachine.redefineClasses(java.util.Map). It will be unsuccessful if the signature of the class has changed (see the JDI spec). The JShell-core is designed to adapt to unsuccessful redefine.

Specified by:: redefine in interface ExecutionControl
Parameters:: cbcs - the class name and bytecodes to redefine
Throws:: ExecutionControl.ClassInstallException - exception occurred redefining the classes, some or all were not redefined; ExecutionControl.EngineTerminationException - the execution engine has terminated

referenceType

protected ReferenceType referenceType(VirtualMachine vm, String name)

Returns the JDI ReferenceType corresponding to the specified class name.

Parameters:: vm - the current JDI VirtualMachine as returned by vm(); name - the class name to look-up
Returns:: the corresponding ReferenceType

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