| | |
- WebKit.Object.Object(__builtin__.object, MiscUtils.NamedValueAccess.NamedValueAccess)
-
- Servlet
class Servlet(WebKit.Object.Object) |
| |
A general servlet.
A servlet is a key portion of a server-based application that implements
the semantics of a particular request by providing a response.
This abstract class defines servlets at a very high level.
Most often, developers will subclass HTTPServlet or even Page.
Servlets can be created once, then used and destroyed, or they may be
reused several times over (it's up to the server). Therefore, servlet
developers should take the proper actions in awake() and sleep()
so that reuse can occur.
Objects that participate in a transaction include:
* Application
* Request
* Transaction
* Session
* Servlet
* Response
The awake(), respond() and sleep() methods form a message sandwich.
Each is passed an instance of Transaction which gives further access
to all the objects involved.
|
| |
- Method resolution order:
- Servlet
- WebKit.Object.Object
- __builtin__.object
- MiscUtils.NamedValueAccess.NamedValueAccess
Methods defined here:
- __init__(self)
- Subclasses must invoke super.
- awake(self, trans)
- Send the awake message.
This message is sent to all objects that participate in the
request-response cycle in a top-down fashion, prior to respond().
Subclasses must invoke super.
- canBeReused(self)
- Returns whether a single servlet instance can be reused.
The default is True, but subclasses con override to return False.
Keep in mind that performance may seriously be degraded if instances
can't be reused. Also, there's no known good reasons not to reuse
an instance. Remember the awake() and sleep() methods are invoked
for every transaction. But just in case, your servlet can refuse
to be reused.
- canBeThreaded(self)
- Return whether the servlet can be multithreaded.
This value should not change during the lifetime of the object.
The default implementation returns False.
Note: This is not currently used.
- close(self)
- log(self, message)
- Log a message.
This can be invoked to print messages concerning the servlet.
This is often used by self to relay important information back
to developers.
- name(self)
- Return the name which is simple the name of the class.
Subclasses should *not* override this method.
It is used for logging and debugging.
- open(self)
- respond(self, trans)
- Respond to a request.
- runMethodForTransaction(self, trans, method, *args, **kw)
- runTransaction(self, trans)
- serverSidePath(self, path=None)
- Return the filesystem path of the page on the server.
- setFactory(self, factory)
- sleep(self, trans)
- Send the sleep message.
Methods inherited from WebKit.Object.Object:
- deprecated(self, method)
- Output a deprecation warning.
The implementation of WebKit sometimes invokes this method which prints
a warning that the method you are using has been deprecated.
This method expects that deprecated methods say so at the beginning of
their doc string and terminate that msg with @. For example:
DEPRECATED: Class.foo() on 01/24/01 in ver 0.5. Use Class.bar() instead. @
Putting this information in the doc string is important for accuracy
in the generated docs.
Example call:
self.deprecated(self.foo)
Data descriptors inherited from WebKit.Object.Object:
- __dict__
- dictionary for instance variables (if defined)
- __weakref__
- list of weak references to the object (if defined)
Methods inherited from MiscUtils.NamedValueAccess.NamedValueAccess:
- handleUnknownSetKey(self, key)
- hasValueForKey(self, key)
- Check whether key is available.
Returns true if the key is available, although that does not guarantee
that there will not be errors caused by retrieving the key.
- hasValueForName(self, keysString)
- Check whether name is available.
- resetKeyBindings(self)
- Rest all key bindings, releasing alreaedy referenced values.
- setValueForKey(self, key, value)
- Set value for a given key.
Suppose key is 'foo'.
This method sets the value with the following precedence:
1. Public attributes before private attributes
2. Methods before non-methods
More specifically, this method then uses one of the following:
@@ 2000-03-04 ce: fill in
... or invokes handleUnknownSetKey().
- valueForKey(self, key, default=<class MiscUtils.NoDefault>)
- Get value for given key.
Suppose key is 'foo'.
This method returns the value with the following precedence:
1. Methods before non-methods
2. Public attributes before private attributes
More specifically, this method then returns one of the following:
* self.foo()
* self._foo()
* self.foo
* self._foo
... or default, if it was specified,
otherwise invokes and returns result of valueForUnknownKey().
Note that valueForUnknownKey() normally returns an exception.
See valueForName() which is a more advanced version of this method
that allows multiple, qualified keys.
- valueForKeySequence(self, listOfKeys, default=None)
- Get the value for the given list of keys.
- valueForName(self, keysString, default=None)
- Get the value for the given keysString.
This is the more advanced version of valueForKey(), which can only
handle single names. This method can handle
'foo', 'foo1.foo2', 'a.b.c.d', etc.
It will traverse dictionaries if needed.
- valueForUnknownKey(self, key, default)
- valuesForNames(self, keys, default=None, defaults=None, forgive=0, includeNames=0)
- Get all values for given names.
Returns a list of values that match the given keys, each of which is
passed through valueForName() and so could be of the form 'a.b.c'.
keys and defaults are sequences.
default is any kind of object.
forgive and includeNames are flags.
If default is not None, then it is substituted when a key is not found.
Otherwise, if defaults is not None, then its corresponding/parallel
value for the current key is substituted when a key is not found.
Otherwise, if forgive is true, then unknown keys simply don't produce
any values.
Otherwise, if default and defaults are None, and forgive is false,
then the unknown keys will probably raise an exception through
self.valueForUnknownKey() although that method can always return
a final, default value.
if keys is None, then None is returned.
If keys is an empty list, then None is returned.
Often these last four arguments are specified by key.
Examples:
names = ['origin.x', 'origin.y', 'size.width', 'size.height']
obj.valuesForNames(names)
obj.valuesForNames(names, default=0.0)
obj.valuesForNames(names, defaults=[0.0, 0.0, 100.0, 100.0])
obj.valuesForNames(names, forgive=0)
@@ 2000-03-04 ce: includeNames is only supported when forgive=1.
It should be supported for the other cases.
It should be documented.
It should be included in the test cases.
| |