1 |
## -------------------------------------------------------------------------------- |
## --------------------------------------------------------------------------- |
2 |
## $Id$ |
## $Id$ |
3 |
## -------------------------------------------------------------------------------- |
## --------------------------------------------------------------------------- |
4 |
## $Log$ |
## $Log$ |
5 |
|
## Revision 1.7 2003/02/18 18:34:35 joko |
6 |
|
## + fix: just logs if possible (sub log_basic) |
7 |
|
## |
8 |
|
## Revision 1.6 2003/02/11 11:04:27 joko |
9 |
|
## + metadata (args, caller, etc.) are now stored inside {__bridge} |
10 |
|
## |
11 |
|
## Revision 1.5 2003/02/09 16:24:46 joko |
12 |
|
## + pseudo constructor mechanism by calling method 'constructor' on object instantiation |
13 |
|
## |
14 |
|
## Revision 1.4 2003/01/22 17:56:49 root |
15 |
|
## + fix: just use the logger if it's available |
16 |
|
## |
17 |
|
## Revision 1.3 2003/01/20 16:54:22 joko |
18 |
|
## + sub fromPackage: refactored from libp's 'getNewPerlObjFromPkgName' or s.th.l.th. |
19 |
|
## |
20 |
|
## Revision 1.2 2002/12/27 16:05:42 joko |
21 |
|
## + played with Devel::CallerItem and Devel::StackTrace |
22 |
|
## |
23 |
## Revision 1.1 2002/12/13 21:46:29 joko |
## Revision 1.1 2002/12/13 21:46:29 joko |
24 |
## + initial check-in |
## + initial check-in |
25 |
## |
## |
26 |
## -------------------------------------------------------------------------------- |
## --------------------------------------------------------------------------- |
27 |
|
|
28 |
|
|
29 |
package DesignPattern::Object; |
package DesignPattern::Object; |
31 |
use strict; |
use strict; |
32 |
use warnings; |
use warnings; |
33 |
|
|
34 |
|
|
35 |
|
use Data::Dumper; |
36 |
|
#use Devel::CallerItem; |
37 |
|
#use Devel::StackTrace; |
38 |
|
|
39 |
|
|
40 |
|
my $_dp_globals; |
41 |
|
|
42 |
|
$_dp_globals = { |
43 |
|
TRACE => 0, |
44 |
|
}; |
45 |
|
|
46 |
|
|
47 |
|
sub new { |
48 |
|
|
49 |
|
# the classname in most cases |
50 |
|
my $classname = shift; |
51 |
|
|
52 |
|
# use already blessed reference, if passed in - else use the very classname |
53 |
|
my $class = ref ($classname) || $classname; |
54 |
|
|
55 |
|
#$self->log_basic( "$classname->new( ... )" . "\t[via " . __PACKAGE__ . "]" , 'debug'); |
56 |
|
|
57 |
|
# the base for our object - a plain perl hash, which .... |
58 |
|
my $self = {}; |
59 |
|
# note: |
60 |
|
# this makes an instance of an arbitrary perl variable, |
61 |
|
# the most often used for this purpose is - guess it - the hash, |
62 |
|
# since it resembles object-properties in a convenient way: |
63 |
|
# $object->{property} = 'Hello World!'; |
64 |
|
# if you _do_ care about privacy you might take a look |
65 |
|
# at CPAN's Tie::SecureHash or Class::Contract ... have fun! |
66 |
|
|
67 |
|
# TODO: what about logging in here? inherit from |
68 |
|
# DesignPattern::Object::Logger for this purpose.... |
69 |
|
# ... or would this give us (harmful) circular module dependencies??? |
70 |
|
#$self->log_basic( __PACKAGE__ . "->new( @args )", 'debug' ); # this is not "common"! |
71 |
|
|
72 |
|
|
73 |
|
# remember the stacktrace: abstract this out (DesignPattern::Object::Trace) or parametrize! |
74 |
|
#my $trace = Devel::StackTrace->new(); |
75 |
|
#print Dumper($trace); |
76 |
|
#print Dumper($trace->frame(1)->args()); |
77 |
|
|
78 |
|
#print "args: ", $self->{'__caller'}->hasargs(), "\n"; |
79 |
|
|
80 |
|
#print Dumper($self); |
81 |
|
#exit; |
82 |
|
|
83 |
|
|
84 |
|
# argument-handling ... |
85 |
|
|
86 |
|
# ... get them ... |
87 |
|
my @args = (); |
88 |
|
@_ && (@args = @_); |
89 |
|
|
90 |
|
# ... check if we can coerce them into an array (this needs an even number of arguments) |
91 |
|
my $argcount = $#args + 1; |
92 |
|
my $fract = $argcount / 2; |
93 |
|
|
94 |
|
my $seperate = pop @args if $fract != int($fract); |
95 |
|
|
96 |
|
# mixin arguments |
97 |
|
$self = { @args }; |
98 |
|
|
99 |
|
# scan for arguments prefixed by a double underscore '__' |
100 |
|
foreach (keys %$self) { |
101 |
|
if (/^__(.+?)$/) { |
102 |
|
$self->{__bridge}->{$1} = $self->{$_}; |
103 |
|
delete $self->{$_}; |
104 |
|
} |
105 |
|
} |
106 |
|
|
107 |
|
# mixin seperate - FIXME: should this not be done after blessing? |
108 |
|
$self->{__bridge}->{'arg'} = $seperate if $seperate; |
109 |
|
|
110 |
|
# ... bless hash into object using classname |
111 |
|
bless $self, $class; |
112 |
|
|
113 |
|
# remember the caller |
114 |
|
$self->{__bridge}->{caller_module} = caller; |
115 |
|
#print Dumper(caller(2)); |
116 |
|
#exit; |
117 |
|
|
118 |
|
$self->{__bridge}->{class_name} = $classname; |
119 |
|
|
120 |
|
# patches for backward compatibility |
121 |
|
$self->{'__arg'} = $self->{__bridge}->{'arg'} if $self->{__bridge}->{'arg'}; |
122 |
|
$self->{'__caller'} = $self->{__bridge}->{caller_module} if $self->{__bridge}->{caller_module}; |
123 |
|
$self->{'__classname'} = $self->{__bridge}->{class_name} if $self->{__bridge}->{class_name}; |
124 |
|
|
125 |
|
$self->_init() if $self->can('_init'); |
126 |
|
$self->constructor() if $self->can('constructor'); |
127 |
|
|
128 |
|
# trace |
129 |
|
#print Dumper($self); |
130 |
|
#exit; |
131 |
|
|
132 |
|
return $self; |
133 |
|
} |
134 |
|
|
135 |
sub _abstract_function { |
sub _abstract_function { |
136 |
my $self = shift; |
my $self = shift; |
137 |
my $self_classname = ref $self; |
my $self_classname = ref $self; |
138 |
my $function_name = shift; |
my $function_name = shift; |
139 |
# was: |
# was: |
140 |
# $logger->error( __PACKAGE__ . ": function \"$fName\" is an abstract method, please implement it in \"$class\""); |
$self->log_basic( __PACKAGE__ . ": function '$function_name' is an abstract method, please implement it in '$self_classname'.", 'warning'); |
141 |
# is: |
# is: |
142 |
die( __PACKAGE__ . ": Function '$function_name' is an abstract method, please implement it in '$self_classname'."); |
#die( __PACKAGE__ . ": Function '$function_name' is an abstract method, please implement it in '$self_classname'."); |
143 |
#exit; |
#exit; |
144 |
} |
} |
145 |
|
|
146 |
|
sub fromPackage { |
147 |
|
my $self = shift; |
148 |
|
#my $self_classname = ref $self; |
149 |
|
my $pkgname = shift; |
150 |
|
my @args = @_; |
151 |
|
# my $args = shift; |
152 |
|
|
153 |
|
# my $caller = $self->{'__caller'}; |
154 |
|
|
155 |
|
#print Dumper($args); |
156 |
|
|
157 |
|
$self->log_basic( __PACKAGE__ . "->fromPackage( pkgname $pkgname args @args )", 'debug'); |
158 |
|
|
159 |
|
# perl-load |
160 |
|
my $evstring = "use $pkgname;"; |
161 |
|
eval($evstring); |
162 |
|
|
163 |
|
# report errors |
164 |
|
if ($@) { |
165 |
|
# build error-messages |
166 |
|
my $errmsg_native = __PACKAGE__ . ':' . __LINE__ . " Error in eval \"$evstring\": " . $@; |
167 |
|
#my $classname = $self->{__classname}; |
168 |
|
my $errmsg_critical = ''; |
169 |
|
if ($errmsg_native =~ m/Can't locate (.+?) in \@INC/) { |
170 |
|
$errmsg_critical = "Could not instantiate object from package '$pkgname' ('$1' not found)."; |
171 |
|
} else { |
172 |
|
$errmsg_critical = $errmsg_native; |
173 |
|
} |
174 |
|
# write error to logging-output (console|file|database) |
175 |
|
$self->log_basic( $errmsg_native, 'debug' ); |
176 |
|
$self->log_basic( $errmsg_critical, 'warning' ); |
177 |
|
return; |
178 |
|
} |
179 |
|
|
180 |
|
# object-creation |
181 |
|
my $object = $pkgname->new(@args); |
182 |
|
|
183 |
|
# run boot-methods on object |
184 |
|
$object->_init() if $object->can('_init'); |
185 |
|
$object->constructor() if $object->can('constructor'); |
186 |
|
|
187 |
|
return $object; |
188 |
|
} |
189 |
|
|
190 |
|
sub log_basic { |
191 |
|
my $self = shift; |
192 |
|
my $message = shift; |
193 |
|
my $level = shift; |
194 |
|
|
195 |
|
if ($_dp_globals->{TRACE} || ($level && $level =~ /warning|error|critical/)) { |
196 |
|
print $level, ": ", $message, "\n"; |
197 |
|
} |
198 |
|
|
199 |
|
# get logger instance |
200 |
|
if (!$_dp_globals->{logger}) { |
201 |
|
$_dp_globals->{logger} = eval { Log::Dispatch::Config->instance; }; |
202 |
|
} |
203 |
|
|
204 |
|
if ($_dp_globals->{logger}) { |
205 |
|
$_dp_globals->{logger}->log($level, $message); |
206 |
|
#} else { |
207 |
|
#print $level, ": ", $message, "\n"; |
208 |
|
} |
209 |
|
|
210 |
|
} |
211 |
|
|
212 |
1; |
1; |
213 |
|
__END__ |