Package org.python.core

Class imp

java.lang.Object
org.python.core.imp
public class imp extends Object
Utility functions for "import" support. Note that this class tries to match the names of the corresponding functions from CPython's Python/import.c. In these cases we use CPython's function naming style (underscores and all lowercase) instead of Java's typical camelCase style so that it's easier to compare with import.c.

  • Field Details

  • Method Details

    • getSyspathJavaLoader

      public static ClassLoader getSyspathJavaLoader()

    • getParentClassLoader

      public static ClassLoader getParentClassLoader()
      Selects the parent class loader for Jython, to be used for dynamically loaded classes and resources. Chooses between the current and context class loader based on the following criteria:
      • If both are the same class loader, return that class loader.
      • If either is null, then the non-null one is selected.
      • If both are not null, and a parent/child relationship can be determined, then the child is selected.
      • If both are not null and not on a parent/child relationship, then the current class loader is returned (since it is likely for the context class loader to not see the Jython classes)
      Returns:
      the parent class loader for Jython or null if both the current and context class loaders are null.

    • addModule

      public static PyModule addModule(String name)
      If the given name is found in sys.modules, the entry from there is returned. Otherwise a new PyModule is created for the name and added to sys.modules. Creating the module does not execute the body of the module to initialise its attributes.
      Parameters:
      name - fully-qualified name of the module
      Returns:
      created PyModule

    • readCode

      public static byte[] readCode(String name, InputStream fp, boolean testing) throws IOException
      As readCodeData(String, InputStream, boolean, long) but do not check last-modified time and return only the class file bytes as an array.
      Parameters:
      name - of source file (used for identification in error/log messages)
      fp - stream from which to read class file (closed when read)
      testing - if true, failures are signalled by a null not an exception
      Returns:
      the class file bytes as an array or null on failure (if testing).
      Throws:
      PyException - ImportError on API or last-modified time mismatch
      IOException - from read failures

    • readCode

      public static byte[] readCode(String name, InputStream fp, boolean testing, long sourceLastModified) throws IOException
      As readCodeData(String, InputStream, boolean, long) but return only the class file bytes as an array.
      Parameters:
      name - of source file (used for identification in error/log messages)
      fp - stream from which to read class file (closed when read)
      testing - if true, failures are signalled by a null not an exception
      sourceLastModified - time expected to match MTime annotation in the class file
      Returns:
      the class file bytes as an array or null on failure (if testing).
      Throws:
      PyException - ImportError on API or last-modified time mismatch
      IOException - from read failures

    • readCodeData

      public static imp.CodeData readCodeData(String name, InputStream fp, boolean testing) throws IOException
      As readCodeData(String, InputStream, boolean, long) but do not check last-modified time.
      Parameters:
      name - of source file (used for identification in error/log messages)
      fp - stream from which to read class file (closed when read)
      testing - if true, failures are signalled by a null not an exception
      Returns:
      the CodeData bundle or null on failure (if testing).
      Throws:
      PyException - ImportError on API mismatch
      IOException - from read failures

    • readCodeData

      public static imp.CodeData readCodeData(String name, InputStream fp, boolean testing, long sourceLastModified) throws IOException, PyException
      Create a imp.CodeData object bundling the contents of a class file (given as a stream), source-last-modified time supplied, and the name of the file taken from annotations on the class. On the way, the method checks the API version annotation matches the current process, and that the org.python.compiler.MTime annotation matches the source-last-modified time passed in.
      Parameters:
      name - of source file (used for identification in error/log messages)
      fp - stream from which to read class file (closed when read)
      testing - if true, failures are signalled by a null not an exception
      sourceLastModified - time expected to match MTime annotation in the class file
      Returns:
      the CodeData bundle or null on failure (if testing).
      Throws:
      PyException - ImportError on API or last-modified time mismatch
      IOException - from read failures

    • compileSource

      public static byte[] compileSource(String name, File source)
      Compile Python source in file to a class file represented by a byte array.
      Parameters:
      name - of module (class name will be name$py)
      source - file containing the source
      Returns:
      Java byte code as array

    • compileSource

      public static byte[] compileSource(String name, File source, String filename)
      Compile Python source in file to a class file represented by a byte array.
      Parameters:
      name - of module (class name will be name$py)
      source - file containing the source
      filename - explicit source file name (or null to use that in source)
      Returns:
      Java byte code as array

    • compileSource

      @Deprecated public static byte[] compileSource(String name, File source, String sourceFilename, String compiledFilename)
      Deprecated.
      Use compileSource(String, File, String) instead.
      Compile Python source in file to a class file represented by a byte array.
      Parameters:
      name - of module (class name will be name$py)
      source - file containing the source
      sourceFilename - explicit source file name (or null to use that in source)
      compiledFilename - ignored (huh?)
      Returns:
      Java byte code as array

    • makeCompiledFilename

      public static String makeCompiledFilename(String filename)
      Remove the last three characters of a file name and add the compiled suffix "$py.class".

    • cacheCompiledSource

      public static String cacheCompiledSource(String sourceFilename, String compiledFilename, byte[] compiledSource)
      Stores the bytes in compiledSource in compiledFilename. If compiledFilename is null, it's set to the results of makeCompiledFilename(sourcefileName). If sourceFilename is null or set to UNKNOWN_SOURCEFILE, then null is returned.
      Returns:
      the compiledFilename eventually used; or null if a compiledFilename couldn't be determined or if an error was thrown while writing to the cache file.

    • compileSource

      public static byte[] compileSource(String name, InputStream source, String filename)
      Compile Python source to a class file represented by a byte array.
      Parameters:
      name - of module (class name will be name$py)
      source - open input stream (will be closed)
      filename - of source (or null if unknown)
      Returns:
      Java byte code as array

    • compileSource

      public static byte[] compileSource(String name, InputStream source, String filename, long mtime)
      Compile Python source to a class file represented by a byte array.
      Parameters:
      name - of module (class name will be name$py)
      source - open input stream (will be closed)
      filename - of source (or null if unknown)
      mtime - last-modified time of source, to annotate class
      Returns:
      Java byte code as array

    • createFromSource

      public static PyObject createFromSource(String name, InputStream fp, String filename)

    • createFromSource

      public static PyObject createFromSource(String name, InputStream fp, String filename, String outFilename)

    • createFromSource

      public static PyObject createFromSource(String name, InputStream fp, String filename, String outFilename, long mtime)
      Compile Jython source (as an InputStream) to a module.
      Parameters:
      name - of the module to create (class will be name$py)
      fp - opened on the (Jython) source to compile (will be closed)
      filename - of the source backing fp (to embed in class as data)
      outFilename - in which to write the compiled class
      mtime - last modified time of the file backing fp
      Returns:
      created module

    • createFromCode

      public static PyObject createFromCode(String name, PyCode c)
      Returns a module with the given name whose contents are the results of running c. __file__ is set to whatever is in c.

    • createFromCode

      public static PyObject createFromCode(String name, PyCode c, String moduleLocation)
      Return a Python module with the given name whose attributes are the result of running PyCode c. If moduleLocation != null it is used to set __file__ .

      In normal circumstances, if c comes from a local .py file or compiled $py.class class the caller should should set moduleLocation to something like new File(moduleLocation).getAbsolutePath(). If c comes from a remote file or is a JAR, moduleLocation should be the full URI for that source or class.

      Parameters:
      name - fully-qualified name of the module
      c - code supplying the module
      moduleLocation - to become __file__ if not null
      Returns:
      the module object

    • getImporter

      public static PyObject getImporter(PyObject p)

    • loadFromCompiled

      public static PyObject loadFromCompiled(String name, InputStream stream, String sourceName, String compiledName)

    • caseok

      public static boolean caseok(File file, String filename)
      Check that the canonical name of file matches filename, case-sensitively, even when the OS platform is case-insensitive. This is used to obtain as a check during import on platforms (Windows) that may be case-insensitive regarding file open. It is assumed that file was derived from attempting to find filename, so it returns true on a case-sensitive platform.

      Algorithmically, we return true if any of the following is true:

      • Options.caseok is true (default is false).
      • The platform is case sensitive (according to PlatformUtil.isCaseInsensitive())
      • The name part of the canonical path of file starts with filename
      • The name of any sibling (in the same directory as) file equals filename
      and false otherwise.
      Parameters:
      file - to be tested
      filename - to be matched
      Returns:
      file matches filename

    • load

      public static PyObject load(String name)
      Load the module by name. Upon loading the module it will be added to sys.modules.
      Parameters:
      name - the name of the module to load
      Returns:
      the loaded module

    • fileSystemDecode

      public static String fileSystemDecode(PyObject p, boolean raiseImportError)
      A wrapper for Py.fileSystemDecode(PyObject) for project internal use within the import mechanism to convert decoding errors that occur during import to either null or Py.ImportError(String) calls (and a log message), which usually results in quiet failure.
      Parameters:
      p - assumed to be a (partial) file path
      raiseImportError - if true and p cannot be decoded raise ImportError.
      Returns:
      String form of the object p (or null).

    • fileSystemDecode

      public static String fileSystemDecode(PyObject p)
      For project internal use, equivalent to fileSystemDecode(p, true) (see fileSystemDecode(PyObject, boolean)).
      Parameters:
      p - assumed to be a (partial) file path
      Returns:
      String form of the object p.

    • importName

      public static PyObject importName(String name, boolean top)
      Import a module by name.
      Parameters:
      name - the name of the package to import
      top - if true, return the top module in the name, otherwise the last
      Returns:
      an imported module (Java or Python)

    • importName

      public static PyObject importName(String name, boolean top, PyObject modDict, PyObject fromlist, int level)
      Import a module by name. This supports the default __import__() function __builtin__.__import__. Locks the import system while it operates.
      Parameters:
      name - the fully-qualified name of the package/module to import
      top - if true, return the top module in the name, otherwise the last
      modDict - the __dict__ of the importing module (used for name in relative import)
      fromlist - list of names being imported
      level - 0=absolute, n>0=relative levels to go up, -1=try relative then absolute.
      Returns:
      an imported module (Java or Python)

    • importOne

      @Deprecated public static PyObject importOne(String mod, PyFrame frame)
      Deprecated.
      Called from jython generated code when a statement like "import spam" is executed.

    • importOne

      public static PyObject importOne(String mod, PyFrame frame, int level)
      Called from jython generated code when a statement like "import spam" is executed.

    • importOneAs

      @Deprecated public static PyObject importOneAs(String mod, PyFrame frame)
      Deprecated.
      Called from jython generated code when a statement like "import spam as foo" is executed.

    • importOneAs

      public static PyObject importOneAs(String mod, PyFrame frame, int level)
      Called from jython generated code when a statement like "import spam as foo" is executed.

    • importFrom

      @Deprecated public static PyObject[] importFrom(String mod, String[] names, PyFrame frame)
      Deprecated.
      use importFrom with level param.
      replaced by importFrom with level param. Kept for backwards compatibility.

    • importFrom

      public static PyObject[] importFrom(String mod, String[] names, PyFrame frame, int level)
      Called from jython generated code when a statement like "from spam.eggs import foo, bar" is executed.

    • importFromAs

      @Deprecated public static PyObject[] importFromAs(String mod, String[] names, PyFrame frame)
      Deprecated.
      use importFromAs with level param.
      replaced by importFromAs with level param. Kept for backwards compatibility.

    • importFromAs

      public static PyObject[] importFromAs(String mod, String[] names, String[] asnames, PyFrame frame, int level)
      Called from jython generated code when a statement like "from spam.eggs import foo as spam" is executed.

    • importAll

      public static void importAll(String mod, PyFrame frame, int level)
      Called from jython generated code when a statement like "from spam.eggs import *" is executed.

    • importAll

      @Deprecated public static void importAll(String mod, PyFrame frame)
      Deprecated.

    • importAll

      public static void importAll(PyObject module, PyFrame frame)

    • getAPIVersion

      public static int getAPIVersion()