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Class DirectExecutionControl

java.lang.Object

jdk.jshell.execution.DirectExecutionControl

All Implemented Interfaces:: AutoCloseable, ExecutionControl

Direct Known Subclasses:: LocalExecutionControl, RemoteExecutionControl

public class DirectExecutionControl extends Object implements ExecutionControl

An ExecutionControl implementation that runs in the current process. May be used directly, or over a channel with Util.forwardExecutionControl(ExecutionControl, java.io.ObjectInput, java.io.ObjectOutput).

Since:: 9

Nested Class Summary

Nested classes/interfaces declared in interface jdk.jshell.spi.ExecutionControl

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

Constructor Summary

Constructor	Description
`DirectExecutionControl()`	Create an instance using the default class loading.
`DirectExecutionControl(LoaderDelegate loaderDelegate)`	Creates an instance, delegating loader operations to the specified delegate.

Method Summary

Modifier and Type	Method	Description
`void`	`addToClasspath(String cp)`	Adds the path to the execution class path.
`protected void`	`classesRedefined(ExecutionControl.ClassBytecodes[] cbcs)`	Notify that classes have been redefined.
`protected void`	`clientCodeEnter()`	Marks entry into user code.
`protected void`	`clientCodeLeave()`	Marks departure from user code.
`void`	`close()`	Shuts down this execution engine.
`Object`	`extensionCommand(String command, Object arg)`	Run a non-standard command (or a standard command from a newer version).
`protected Class<?>`	`findClass(String name)`	Finds the class with the specified binary name.
`protected String`	`invoke(Method doitMethod)`	Invoke the specified "doit-method", a static method with no parameters.
`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`	`redefine(ExecutionControl.ClassBytecodes[] cbcs)`	Attempts to redefine previously loaded classes.
`void`	`stop()`	Interrupts a running invoke.
`protected String`	`throwConvertedInvocationException(Throwable cause)`	Converts incoming exceptions in user code into instances of subtypes of `ExecutionControl.ExecutionControlException` and throws the converted exception.
`protected String`	`throwConvertedOtherException(Throwable ex)`	Converts incoming exceptions in agent code into instances of subtypes of `ExecutionControl.ExecutionControlException` and throws the converted exception.
`protected static String`	`valueString(Object value)`	Converts the `Object` value from `ExecutionControl.invoke(String, String)` or `ExecutionControl.varValue(String, String)` to `String`.
`String`	`varValue(String className, String varName)`	Returns the value of a variable.

Methods declared in class java.lang.Object

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

Constructor Details

DirectExecutionControl

public DirectExecutionControl(LoaderDelegate loaderDelegate)

Creates an instance, delegating loader operations to the specified delegate.

Parameters:: loaderDelegate - the delegate to handle loading classes

DirectExecutionControl

public DirectExecutionControl()

Create an instance using the default class loading.

Method Details

load

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

Description copied from interface: ExecutionControl

Attempts to load new classes.

Specified by:: load in interface ExecutionControl
Parameters:: cbcs - the class name and bytecodes to load
Throws:: ExecutionControl.ClassInstallException - exception occurred loading the classes, some or all were not loaded; ExecutionControl.NotImplementedException - if not implemented; ExecutionControl.EngineTerminationException - the execution engine has terminated

redefine

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

Description copied from interface: ExecutionControl

Attempts to redefine previously loaded classes.

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.NotImplementedException - if not implemented; ExecutionControl.EngineTerminationException - the execution engine has terminated

classesRedefined

protected void classesRedefined(ExecutionControl.ClassBytecodes[] cbcs) throws ExecutionControl.NotImplementedException, ExecutionControl.EngineTerminationException

Notify that classes have been redefined.

Parameters:: cbcs - the class name and bytecodes to redefine
Throws:: ExecutionControl.NotImplementedException - if not implemented; ExecutionControl.EngineTerminationException - the execution engine has terminated

invoke

public String invoke(String className, String methodName) throws ExecutionControl.RunException, ExecutionControl.InternalException, ExecutionControl.EngineTerminationException

Description copied from interface: ExecutionControl

Invokes an executable Snippet by calling a method on the specified wrapper class. The method must have no arguments and return String.

Specified by:: invoke in interface ExecutionControl
Parameters:: className - the class whose method should be invoked; methodName - the name of method to invoke
Returns:: the result of the execution or null if no result
Throws:: ExecutionControl.UserException - the invoke raised a user exception; ExecutionControl.ResolutionException - the invoke attempted to directly or indirectly invoke an unresolved snippet; ExecutionControl.StoppedException - if the invoke() was canceled by ExecutionControl.stop(); ExecutionControl.InternalException - an internal problem occurred; ExecutionControl.EngineTerminationException - the execution engine has terminated; ExecutionControl.RunException

varValue

public String varValue(String className, String varName) throws ExecutionControl.RunException, ExecutionControl.EngineTerminationException, ExecutionControl.InternalException

Description copied from interface: ExecutionControl

Returns the value of a variable.

Specified by:: varValue in interface ExecutionControl
Parameters:: className - the name of the wrapper class of the variable; varName - the name of the variable
Returns:: the value of the variable
Throws:: ExecutionControl.UserException - formatting the value raised a user exception; ExecutionControl.ResolutionException - formatting the value attempted to directly or indirectly invoke an unresolved snippet; ExecutionControl.StoppedException - if the formatting the value was canceled by ExecutionControl.stop(); ExecutionControl.EngineTerminationException - the execution engine has terminated; ExecutionControl.InternalException - an internal problem occurred; ExecutionControl.RunException

addToClasspath

public void addToClasspath(String cp) throws ExecutionControl.EngineTerminationException, ExecutionControl.InternalException

Description copied from interface: ExecutionControl

Adds the path to the execution class path.

Specified by:: addToClasspath in interface ExecutionControl
Parameters:: cp - the path to add
Throws:: ExecutionControl.EngineTerminationException - the execution engine has terminated; ExecutionControl.InternalException - an internal problem occurred

stop

public void stop() throws ExecutionControl.EngineTerminationException, ExecutionControl.InternalException

Interrupts a running invoke.

Not supported.

Specified by:: stop in interface ExecutionControl
Throws:: ExecutionControl.EngineTerminationException - the execution engine has terminated; ExecutionControl.InternalException - an internal problem occurred

extensionCommand

public Object extensionCommand(String command, Object arg) throws ExecutionControl.RunException, ExecutionControl.EngineTerminationException, ExecutionControl.InternalException

Description copied from interface: ExecutionControl

Run a non-standard command (or a standard command from a newer version).

Specified by:: extensionCommand in interface ExecutionControl
Parameters:: command - the non-standard command; arg - the commands argument
Returns:: the commands return value
Throws:: ExecutionControl.UserException - the command raised a user exception; ExecutionControl.ResolutionException - the command attempted to directly or indirectly invoke an unresolved snippet; ExecutionControl.StoppedException - if the command was canceled by ExecutionControl.stop(); ExecutionControl.EngineTerminationException - the execution engine has terminated; ExecutionControl.NotImplementedException - if not implemented; ExecutionControl.InternalException - an internal problem occurred; ExecutionControl.RunException

close

public void close()

Description copied from interface: ExecutionControl

Shuts down this execution engine. Implementation should free all resources held by this execution engine.

No calls to methods on this interface should be made after close.

Specified by:: close in interface AutoCloseable
Specified by:: close in interface ExecutionControl

findClass

protected Class<?> findClass(String name) throws ClassNotFoundException

Finds the class with the specified binary name.

Parameters:: name - the binary name of the class
Returns:: the Class Object
Throws:: ClassNotFoundException - if the class could not be found

invoke

protected String invoke(Method doitMethod) throws Exception

Invoke the specified "doit-method", a static method with no parameters. The invoke(java.lang.String, java.lang.String) in this class will call this to invoke.

Parameters:: doitMethod - the Method to invoke
Returns:: the value or null
Throws:: Exception - any exceptions thrown by Method.invoke(Object, Object...) or any ExecutionControl.ExecutionControlException to pass-through.

valueString

protected static String valueString(Object value)

Converts the Object value from ExecutionControl.invoke(String, String) or ExecutionControl.varValue(String, String) to String.

Parameters:: value - the value to convert
Returns:: the String representation

throwConvertedInvocationException

protected String throwConvertedInvocationException(Throwable cause) throws ExecutionControl.RunException, ExecutionControl.InternalException

Converts incoming exceptions in user code into instances of subtypes of ExecutionControl.ExecutionControlException and throws the converted exception.

Parameters:: cause - the exception to convert
Returns:: never returns as it always throws
Throws:: ExecutionControl.RunException - for normal exception occurrences; ExecutionControl.InternalException - for internal problems

throwConvertedOtherException

protected String throwConvertedOtherException(Throwable ex) throws ExecutionControl.RunException, ExecutionControl.InternalException

Converts incoming exceptions in agent code into instances of subtypes of ExecutionControl.ExecutionControlException and throws the converted exception.

Parameters:: ex - the exception to convert
Returns:: never returns as it always throws
Throws:: ExecutionControl.RunException - for normal exception occurrences; ExecutionControl.InternalException - for internal problems

clientCodeEnter

protected void clientCodeEnter() throws ExecutionControl.InternalException

Marks entry into user code.

Throws:: ExecutionControl.InternalException - in unexpected failure cases

clientCodeLeave

protected void clientCodeLeave() throws ExecutionControl.InternalException

Marks departure from user code.

Throws:: ExecutionControl.InternalException - in unexpected failure cases

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https://docs.oracle.com/en/java/javase/21/docs/api/jdk.jshell/jdk/jshell/execution/DirectExecutionControl.html