在学习JAVA的时候涉及到了类，对象，方法，域等基本概念。类像一个盒子一样包含各种域和访问更改这些域的方法，而对象是类的特例，比如老师和张老师的关系，老师是一个类，而张老师是一个对象。OOP的关键就是类和对象的使用。
在我学习Python的时候，对模块和类的概念与关系不以为意，在开始动手写脚本的时候不知不觉就昏了头，查阅了些许资料，现写一些小小总结。
为了方便叙述，引入zipfile这个模块的描述，代码比较长，但我们只关心其中大致包含了哪些内容：
>>> import zipfile
>>> help(zipfile)
Help on module zipfile:
NAME
zipfile - Read and write ZIP files.
DESCRIPTION
XXX references to utf-8 need further investigation.
CLASSES
builtins.Exception(builtins.BaseException)
BadZipFile
LargeZipFile
builtins.object
ZipFile
PyZipFile
ZipInfo
class BadZipFile(builtins.Exception)
| Method resolution order:
| BadZipFile
| builtins.Exception
| builtins.BaseException
| builtins.object
|
| Data descriptors defined here:
|
| __weakref__
| list of weak references to the object (if defined)
|
| ----------------------------------------------------------------------
| Methods inherited from builtins.Exception:
|
| __init__(self, /, *args, **kwargs)
| Initialize self. See help(type(self)) for accurate signature.
|
| __new__(*args, **kwargs) from builtins.type
| Create and return a new object. See help(type) for accurate signature.
|
| ----------------------------------------------------------------------
| Methods inherited from builtins.BaseException:
|
| __delattr__(self, name, /)
| Implement delattr(self, name).
|
| __getattribute__(self, name, /)
| Return getattr(self, name).
|
| __reduce__(...)
|
| __repr__(self, /)
| Return repr(self).
|
| __setattr__(self, name, value, /)
| Implement setattr(self, name, value).
|
| __setstate__(...)
|
| __str__(self, /)
| Return str(self).
|
| with_traceback(...)
| Exception.with_traceback(tb) --
| set self.__traceback__ to tb and return self.
|
| ----------------------------------------------------------------------
| Data descriptors inherited from builtins.BaseException:
|
| __cause__
| exception cause
|
| __context__
| exception context
|
| __dict__
|
| __suppress_context__
|
| __traceback__
|
| args
BadZipfile = class BadZipFile(builtins.Exception)
| Method resolution order:
| BadZipFile
| builtins.Exception
| builtins.BaseException
| builtins.object
|
| Data descriptors defined here:
|
| __weakref__
| list of weak references to the object (if defined)
|
| ----------------------------------------------------------------------
| Methods inherited from builtins.Exception:
|
| __init__(self, /, *args, **kwargs)
| Initialize self. See help(type(self)) for accurate signature.
|
| __new__(*args, **kwargs) from builtins.type
| Create and return a new object. See help(type) for accurate signature.
|
| ----------------------------------------------------------------------
| Methods inherited from builtins.BaseException:
|
| __delattr__(self, name, /)
| Implement delattr(self, name).
|
| __getattribute__(self, name, /)
| Return getattr(self, name).
|
| __reduce__(...)
|
| __repr__(self, /)
| Return repr(self).
|
| __setattr__(self, name, value, /)
| Implement setattr(self, name, value).
|
| __setstate__(...)
|
| __str__(self, /)
| Return str(self).
|
| with_traceback(...)
| Exception.with_traceback(tb) --
| set self.__traceback__ to tb and return self.
|
| ----------------------------------------------------------------------
| Data descriptors inherited from builtins.BaseException:
|
| __cause__
| exception cause
|
| __context__
| exception context
|
| __dict__
|
| __suppress_context__
|
| __traceback__
|
| args
class LargeZipFile(builtins.Exception)
| Raised when writing a zipfile, the zipfile requires ZIP64 extensions
| and those extensions are disabled.
|
| Method resolution order:
| LargeZipFile
| builtins.Exception
| builtins.BaseException
| builtins.object
|
| Data descriptors defined here:
|
| __weakref__
| list of weak references to the object (if defined)
|
| ----------------------------------------------------------------------
| Methods inherited from builtins.Exception:
|
| __init__(self, /, *args, **kwargs)
| Initialize self. See help(type(self)) for accurate signature.
|
| __new__(*args, **kwargs) from builtins.type
| Create and return a new object. See help(type) for accurate signature.
|
| ----------------------------------------------------------------------
| Methods inherited from builtins.BaseException:
|
| __delattr__(self, name, /)
| Implement delattr(self, name).
|
| __getattribute__(self, name, /)
| Return getattr(self, name).
|
| __reduce__(...)
|
| __repr__(self, /)
| Return repr(self).
|
| __setattr__(self, name, value, /)
| Implement setattr(self, name, value).
|
| __setstate__(...)
|
| __str__(self, /)
| Return str(self).
|
| with_traceback(...)
| Exception.with_traceback(tb) --
| set self.__traceback__ to tb and return self.
|
| ----------------------------------------------------------------------
| Data descriptors inherited from builtins.BaseException:
|
| __cause__
| exception cause
|
| __context__
| exception context
|
| __dict__
|
| __suppress_context__
|
| __traceback__
|
| args
class PyZipFile(ZipFile)
| Class to create ZIP archives with Python library files and packages.
|
| Method resolution order:
| PyZipFile
| ZipFile
| builtins.object
|
| Methods defined here:
|
| __init__(self, file, mode='r', compression=0, allowZip64=True, optimize=-1)
|
| writepy(self, pathname, basename='', filterfunc=None)
| Add all files from "pathname" to the ZIP archive.
|
| If pathname is a package directory, search the directory and
| all package subdirectories recursively for all *.py and enter
| the modules into the archive. If pathname is a plain
| directory, listdir *.py and enter all modules. Else, pathname
| must be a Python *.py file and the module will be put into the
| archive. Added modules are always module.pyo or module.pyc.
| This method will compile the module.py into module.pyc if
| necessary.
| If filterfunc(pathname) is given, it is called with every argument.
| When it is False, the file or directory is skipped.
|
| ----------------------------------------------------------------------
| Methods inherited from ZipFile:
|
| __del__(self)
| Call the "close()" method in case the user forgot.
|
| __enter__(self)
|
| __exit__(self, type, value, traceback)
|
| close(self)
| Close the file, and for mode "w" and "a" write the ending
| records.
|
| extract(self, member, path=None, pwd=None)
| Extract a member from the archive to the current working directory,
| using its full name. Its file information is extracted as accurately
| as possible. `member' may be a filename or a ZipInfo object. You can
| specify a different directory using `path'.
|
| extractall(self, path=None, members=None, pwd=None)
| Extract all members from the archive to the current working
| directory. `path' specifies a different directory to extract to.
| `members' is optional and must be a subset of the list returned
| by namelist().
|
| getinfo(self, name)
| Return the instance of ZipInfo given 'name'.
|
| infolist(self)
| Return a list of class ZipInfo instances for files in the
| archive.
|
| namelist(self)
| Return a list of file names in the archive.
|
| open(self, name, mode='r', pwd=None)
| Return file-like object for 'name'.
|
| printdir(self, file=None)
| Print a table of contents for the zip file.
|
| read(self, name, pwd=None)
| Return file bytes (as a string) for name.
|
| setpassword(self, pwd)
| Set default password for encrypted files.
|
| testzip(self)
| Read all the files and check the CRC.
|
| write(self, filename, arcname=None, compress_type=None)
| Put the bytes from filename into the archive under the name
| arcname.
|
| writestr(self, zinfo_or_arcname, data, compress_type=None)
| Write a file into the archive. The contents is 'data', which
| may be either a 'str' or a 'bytes' instance; if it is a 'str',
| it is encoded as UTF-8 first.
| 'zinfo_or_arcname' is either a ZipInfo instance or
| the name of the file in the archive.
|
| ----------------------------------------------------------------------
| Data descriptors inherited from ZipFile:
|
| __dict__
| dictionary for instance variables (if defined)
|
| __weakref__
| list of weak references to the object (if defined)
|
| comment
| The comment text associated with the ZIP file.
|
| ----------------------------------------------------------------------
| Data and other attributes inherited from ZipFile:
|
| fp = None
class ZipFile(builtins.object)
| Class with methods to open, read, write, close, list zip files.
|
| z = ZipFile(file, mode="r", compression=ZIP_STORED, allowZip64=True)
|
| file: Either the path to the file, or a file-like object.
| If it is a path, the file will be opened and closed by ZipFile.
| mode: The mode can be either read "r", write "w" or append "a".
| compression: ZIP_STORED (no compression), ZIP_DEFLATED (requires zlib),
| ZIP_BZIP2 (requires bz2) or ZIP_LZMA (requires lzma).
| allowZip64: if True ZipFile will create files with ZIP64 extensions when
| needed, otherwise it will raise an exception when this would
| be necessary.
|
| Methods defined here:
|
| __del__(self)
| Call the "close()" method in case the user forgot.
|
| __enter__(self)
|
| __exit__(self, type, value, traceback)
|
| __init__(self, file, mode='r', compression=0, allowZip64=True)
| Open the ZIP file with mode read "r", write "w" or append "a".
|
| close(self)
| Close the file, and for mode "w" and "a" write the ending
| records.
|
| extract(self, member, path=None, pwd=None)
| Extract a member from the archive to the current working directory,
| using its full name. Its file information is extracted as accurately
| as possible. `member' may be a filename or a ZipInfo object. You can
| specify a different directory using `path'.
|
| extractall(self, path=None, members=None, pwd=None)
| Extract all members from the archive to the current working
| directory. `path' specifies a different directory to extract to.
| `members' is optional and must be a subset of the list returned
| by namelist().
|
| getinfo(self, name)
| Return the instance of ZipInfo given 'name'.
|
| infolist(self)
| Return a list of class ZipInfo instances for files in the
| archive.
|
| namelist(self)
| Return a list of file names in the archive.
|
| open(self, name, mode='r', pwd=None)
| Return file-like object for 'name'.
|
| printdir(self, file=None)
| Print a table of contents for the zip file.
|
| read(self, name, pwd=None)
| Return file bytes (as a string) for name.
|
| setpassword(self, pwd)
| Set default password for encrypted files.
|
| testzip(self)
| Read all the files and check the CRC.
|
| write(self, filename, arcname=None, compress_type=None)
| Put the bytes from filename into the archive under the name
| arcname.
|
| writestr(self, zinfo_or_arcname, data, compress_type=None)
| Write a file into the archive. The contents is 'data', which
| may be either a 'str' or a 'bytes' instance; if it is a 'str',
| it is encoded as UTF-8 first.
| 'zinfo_or_arcname' is either a ZipInfo instance or
| the name of the file in the archive.
|
| ----------------------------------------------------------------------
| Data descriptors defined here:
|
| __dict__
| dictionary for instance variables (if defined)
|
| __weakref__
| list of weak references to the object (if defined)
|
| comment
| The comment text associated with the ZIP file.
|
| ----------------------------------------------------------------------
| Data and other attributes defined here:
|
| fp = None
class ZipInfo(builtins.object)
| Class with attributes describing each file in the ZIP archive.
|
| Methods defined here:
|
| FileHeader(self, zip64=None)
| Return the per-file header as a string.
|
| __init__(self, filename='NoName', date_time=(1980, 1, 1, 0, 0, 0))
|
| ----------------------------------------------------------------------
| Data descriptors defined here:
|
| CRC
|
| comment
|
| compress_size
|
| compress_type
|
| create_system
|
| create_version
|
| date_time
|
| external_attr
|
| extra
|
| extract_version
|
| file_size
|
| filename
|
| flag_bits
|
| header_offset
|
| internal_attr
|
| orig_filename
|
| reserved
|
| volume
error = class BadZipFile(builtins.Exception)
| Method resolution order:
| BadZipFile
| builtins.Exception
| builtins.BaseException
| builtins.object
|
| Data descriptors defined here:
|
| __weakref__
| list of weak references to the object (if defined)
|
| ----------------------------------------------------------------------
| Methods inherited from builtins.Exception:
|
| __init__(self, /, *args, **kwargs)
| Initialize self. See help(type(self)) for accurate signature.
|
| __new__(*args, **kwargs) from builtins.type
| Create and return a new object. See help(type) for accurate signature.
|
| ----------------------------------------------------------------------
| Methods inherited from builtins.BaseException:
|
| __delattr__(self, name, /)
| Implement delattr(self, name).
|
| __getattribute__(self, name, /)
| Return getattr(self, name).
|
| __reduce__(...)
|
| __repr__(self, /)
| Return repr(self).
|
| __setattr__(self, name, value, /)
| Implement setattr(self, name, value).
|
| __setstate__(...)
|
| __str__(self, /)
| Return str(self).
|
| with_traceback(...)
| Exception.with_traceback(tb) --
| set self.__traceback__ to tb and return self.
|
| ----------------------------------------------------------------------
| Data descriptors inherited from builtins.BaseException:
|
| __cause__
| exception cause
|
| __context__
| exception context
|
| __dict__
|
| __suppress_context__
|
| __traceback__
|
| args
FUNCTIONS
is_zipfile(filename)
Quickly see if a file is a ZIP file by checking the magic number.
The filename argument may be a file or file-like object too.
DATA
ZIP_BZIP2 = 12
ZIP_DEFLATED = 8
ZIP_LZMA = 14
ZIP_STORED = 0
__all__ = ['BadZipFile', 'BadZipfile', 'error', 'ZIP_STORED', 'ZIP_DEF...
FILE
d:\python34\lib\zipfile.pyView Code
可以看到,Help on zipfile module列出了zipfile的六个属性：NAME,DESCRIPTION,CLASSES,FUNCTIONS,DATA,FILE。
函数是可以重用的代码，而模块就是可以重用的函数与变量的集合。和JAVA的严谨不一样，你可以往模块中放许多东西，类，定义的函数，甚至独立的域。一个模块对应一个.py文件。每个python程序也是一个模块。JAVA的.java文件是把一个或者多个封装得很好的类放在同一个.java文件中。一个JAVA程序总是在类里找到main入口开始运行。由此看来，.py和.java文件在内容和作用上都有很大差别。从某种意义上来说，.py文件更加像C中的头文件（只是头文件不能运行）。
有意思的是，在python中，一切都是对象，包括函数，数据域，数值等等。所以，模块就是一个盛了很多对象的容器。这个容器被标好标码，你可以通过路径和名字找到它，查阅上面的标码从中拿到你想要的对象，访问、使用或者更改它们。
而类就是小的容器，也是模块的一部分。不同的是，一个类可以衍生出很多很多类。而模块被import之后就只有一个了。
python似乎并不像JAVA一样强调 类和对象的关系，反而强调 对象和对象的关系 以及 对象和实例的关系，这一点让习惯使用JAVA的人有些迷惑。对python而言，“其实都是实例化的”。python的类关系向一棵树，每个叶子之间有两种导航关系：1 子类继承父类;2 子类构建实例。这一点，从type和object的鸡、蛋关系里就能察觉出来。
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