6. Architecture

Previous chapters describe actual implementation experiments. This chapter is for stepping back from the realised code. Apart from analysis (of CPython etc.), it will collect together two broad kinds of idea about the architecture of a Java implementation of Python:

• Ideas tested by the implementation experiments and shown to be useful.

• Untested speculations. These may be tested in due course, in the experimental code of this project, quite likely resulting in some adjustment.

There will also be some issues we don’t know how to address (yet). Hopefully, these give rise to speculations and then tested ideas that address them.

• 6.1. Java Object as Python object
  • 6.1.1. Motivations
  • 6.1.2. Essential Idea
  • 6.1.3. Canonical Implementation
  • 6.1.4. Adopted Implementation
  • 6.1.5. Found Java Type
• 6.2. Object Implementation
  • 6.2.1. Special Methods in Java
  • 6.2.2. Special Methods in Python
  • 6.2.3. __new__ and Java Constructors
  • 6.2.4. Relation of tp_new to the Java constructor
  • 6.2.5. Examples guiding architectural choices
• 6.3. Type Slots
  • 6.3.1. Choice of MethodHandle
  • 6.3.2. Learning from CPython
  • 6.3.3. One-to-One Principle
  • 6.3.4. Potentially Problematic Slots in CPython
  • 6.3.5. Initialisation of Slots
• 6.4. Access to Attributes
  • 6.4.1. A Reminder of the CPython Opcodes
  • 6.4.2. Slots for Attribute Access
  • 6.4.3. Abstract API support for attributes
  • 6.4.4. The Mechanism of Attribute Access
• 6.5. Interpreter Structure
  • 6.5.1. Introduction
  • 6.5.2. Runtime, Thread and Interpreter (CPython)
  • 6.5.3. Use cases
  • 6.5.4. Proposed Model for Jython [untested]
• 6.6. Types of code and frame Object
  • 6.6.1. Several Types of Code
  • 6.6.2. Old Notes (needs rewrite)
• 6.7. Compiled Code (Python to JVM)
• 6.8. Functions Defined in Java
  • 6.8.1. Introduction
  • 6.8.2. Patterns of Method Definition
  • 6.8.3. Argument and Return Value Coercion
• 6.9. Descriptors
  • 6.9.1. Introduction
  • 6.9.2. Descriptors and __getattribute__
  • 6.9.3. Methods in Python (PyFunction)
  • 6.9.4. The @classmethod Decorator (PyClassMethod)
  • 6.9.5. The @staticmethod Decorator (PyStaticMethod)
  • 6.9.6. Descriptors for Built-in Types
  • 6.9.7. Members (PyMemberDescr)
  • 6.9.8. Attributes (PyGetSetDescr)
  • 6.9.9. Built-in Methods (PyMethodDescr)
  • 6.9.10. Special Methods (PyWrapperDescr)
  • 6.9.11. Built-in Class Methods (PyClassMethodDescr)
  • 6.9.12. Built-in Static Methods (PyStaticMethod)

This chapter has diagrams generated with PlantUML (if this diagnostic panel appears):