jdk.jshell.spi (Java SE 19 & JDK 19) (original) (raw)

package jdk.jshell.spi

Defines the Service Provider Interface for pluggable JShell execution engines. The JShell core tracks and compiles Snippets then sends them (represented in a wrapper class) to the execution engine for loading, and in the case of executable Snippets, execution. The JShell implementation includes a default execution engine (currently a remote process which is JDI controlled). By implementing theExecutionControl interface and its generating class, an implementation of the ExecutionControlProvider interface, and installing it withJShell.Builder.executionEngine(String) other execution engines can be used. Where the passed String is anExecutionControl spec.

The ExecutionControl spec is the ExecutionControlProvider name optionally followed by a parameter specification. The syntax of the spec is:

spec := name : params | name name := identifier params := param , params | param | param := identifier ( value )

Where 'name' is the ExecutionControlProvider name. Where 'param' is a Map key fromExecutionControlProvider.defaultParameters() and the parenthesized value; See, for example,JdiExecutionControlProvider. Where 'identifier' is a sequence ofJava identifier part characters from the Basic Multilingual Plane.

For example:

• local
• jdi:hostname(localhost)
• failover:1(jdi),2(jdi:launch(true),timeout(3000)),3(local)

Since:

9

See Also:

• for execution implementation support

• This interface specifies the functionality that must provided to implement a pluggable JShell execution engine.
  Bundles class name with class bytecodes.
  A class install (load or redefine) encountered a problem.
  Unbidden execution engine termination has occurred.
  The abstract base of all ExecutionControl exceptions.
  An internal problem has occurred.
  The command is not implemented.
  An exception indicating that a DeclarationSnippet with unresolved references has been encountered.
  The abstract base of of exceptions specific to running user code.
  A 'normal' user exception occurred.
  The provider used by JShell to generate the execution engine needed to evaluate Snippets.
  Functionality made available to a pluggable JShell execution engine.
  The construction and throw of this exception is embedded in code generated by the JShell core implementation in such a way that, upon executing aRECOVERABLE_DEFINED user method, this exception is thrown.