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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Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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https://docs.oracle.com/en/java/javase/17/docs/api/jdk.jshell/jdk/jshell/execution/DirectExecutionControl.html