| 1 |
## -------------------------------------------------------------------------------- |
| 2 |
## $Id: Bridge.pm,v 1.8 2003/02/14 14:20:05 joko Exp $ |
| 3 |
## -------------------------------------------------------------------------------- |
| 4 |
## $Log: Bridge.pm,v $ |
| 5 |
## Revision 1.8 2003/02/14 14:20:05 joko |
| 6 |
## + modified mixin behaviour |
| 7 |
## |
| 8 |
## Revision 1.7 2003/02/11 10:34:19 joko |
| 9 |
## + loaded module may now lack 'mixin::with' declaration |
| 10 |
## + this gets us the possibility to load modules from any perl namespace |
| 11 |
## + enabled this mechanism |
| 12 |
## |
| 13 |
## Revision 1.6 2003/02/09 16:22:51 joko |
| 14 |
## + pseudo constructor mechanism via options |
| 15 |
## |
| 16 |
## Revision 1.5 2003/01/31 01:19:50 root |
| 17 |
## + fixed: doesn't need Log::Dispatch any more, but uses it if available |
| 18 |
## |
| 19 |
## Revision 1.4 2003/01/20 16:55:15 joko |
| 20 |
## + sub mixinPackage |
| 21 |
## + sub include |
| 22 |
## |
| 23 |
## Revision 1.3 2002/12/16 19:57:12 joko |
| 24 |
## + sub unload |
| 25 |
## |
| 26 |
## Revision 1.2 2002/12/15 02:06:15 joko |
| 27 |
## + feature to be able to specify module in non-perl-style when loading plugins: e.g. $process->load('Setup/Storage') |
| 28 |
## |
| 29 |
## Revision 1.1 2002/12/13 21:46:29 joko |
| 30 |
## + initial check-in |
| 31 |
## |
| 32 |
## -------------------------------------------------------------------------------- |
| 33 |
|
| 34 |
|
| 35 |
package DesignPattern::Bridge; |
| 36 |
|
| 37 |
use strict; |
| 38 |
use warnings; |
| 39 |
|
| 40 |
use base qw( DesignPattern::Object ); |
| 41 |
|
| 42 |
use Data::Dumper; |
| 43 |
|
| 44 |
## ======== object inheritance ======== |
| 45 |
|
| 46 |
# TODO / REFACTORING PROPOSAL |
| 47 |
# leading from Data::Storage to code abstracted out into this module - DesignPattern::Bridge |
| 48 |
# - this is no inheritance and it doesn't have to be |
| 49 |
# - implement this module as a bridge to its sub-modules |
| 50 |
# - use the BridgePattern (http://c2.com/cgi/wiki?BridgePattern) |
| 51 |
# Using patterns was already successfully done with Data::Storage::Handler |
| 52 |
# by implementing the AdapterPattern (http://c2.com/cgi/wiki?AdapterPattern) |
| 53 |
# with Perl's AUTOLOAD-mechanism |
| 54 |
# - try to use Perl's "tie" command to implement this functionality here instead of using AUTOLOAD! |
| 55 |
# - sub getChildNodes |
| 56 |
# - sub run |
| 57 |
|
| 58 |
# 2003-02-11, joko: does this have anything in parallel with CPAN's Class::Inner? |
| 59 |
|
| 60 |
|
| 61 |
# get logger instance |
| 62 |
my $logger = eval { Log::Dispatch::Config->instance; }; |
| 63 |
|
| 64 |
my $meta; |
| 65 |
|
| 66 |
## ======== object constructor ======== |
| 67 |
sub new { |
| 68 |
my $invocant = shift; |
| 69 |
my $class = ref($invocant) || $invocant; |
| 70 |
my @args = (); |
| 71 |
@_ && (@args = @_); |
| 72 |
$logger->debug( __PACKAGE__ . "->new(@args)" ) if $logger; |
| 73 |
my $self = { @_ }; |
| 74 |
|
| 75 |
# trace |
| 76 |
#print "class: $class", "\n"; |
| 77 |
|
| 78 |
# create instance |
| 79 |
bless $self, $class; |
| 80 |
|
| 81 |
return $self; |
| 82 |
} |
| 83 |
|
| 84 |
|
| 85 |
## ======== method overrider ======== |
| 86 |
sub AUTOLOAD2 { |
| 87 |
|
| 88 |
my $self = shift; |
| 89 |
our $AUTOLOAD; |
| 90 |
|
| 91 |
##print "AUTOLOAD\n"; |
| 92 |
|
| 93 |
my $method = $AUTOLOAD; |
| 94 |
$method =~ s/^.*:://; |
| 95 |
|
| 96 |
$logger->debug( __PACKAGE__ . "->" . $method . "(@_)" . " (AUTOLOAD called, not dispatched)" ) if $logger; |
| 97 |
|
| 98 |
## ->DESTROY would - if not declared - trigger an AUTOLOAD also |
| 99 |
return if $method =~ m/::DESTROY$/; |
| 100 |
|
| 101 |
## if ($self->_filter_AUTOLOAD($method)) { |
| 102 |
## $self->_accessStorage(); |
| 103 |
## $self->{STORAGEHANDLE}->$method(@_); |
| 104 |
## } |
| 105 |
|
| 106 |
} |
| 107 |
|
| 108 |
sub _getPluginPackage { |
| 109 |
my $self = shift; |
| 110 |
my $modulename_load = shift; |
| 111 |
|
| 112 |
# substitute slashes through double double-colons to load modules perl-style |
| 113 |
$modulename_load =~ s/\//::/g; |
| 114 |
|
| 115 |
# build full package name |
| 116 |
my $self_classname = ref $self; |
| 117 |
# name |
| 118 |
my $package = $modulename_load; |
| 119 |
|
| 120 |
# if package is absolute, cut away prefix ('/' or '::') |
| 121 |
if ($package !~ s/^:://) { |
| 122 |
# else: prefix with base classname if above name is relative (lacks of '/' or '::') |
| 123 |
$package = $self_classname . '::' . $package |
| 124 |
} |
| 125 |
|
| 126 |
return $package; |
| 127 |
} |
| 128 |
|
| 129 |
sub load { |
| 130 |
|
| 131 |
my $self = shift; |
| 132 |
my $modulename = shift; |
| 133 |
my $options = shift; |
| 134 |
|
| 135 |
if (ref $modulename eq 'ARRAY') { |
| 136 |
foreach (@$modulename) { |
| 137 |
$self->load_single($_, $options); |
| 138 |
} |
| 139 |
} else { |
| 140 |
$self->load_single($modulename, $options); |
| 141 |
} |
| 142 |
|
| 143 |
} |
| 144 |
|
| 145 |
sub load_single { |
| 146 |
|
| 147 |
my $self = shift; |
| 148 |
my $modulename_load = shift; |
| 149 |
|
| 150 |
my $options = shift; |
| 151 |
|
| 152 |
my $self_modulename = ref $self; |
| 153 |
my $package = $self->_getPluginPackage($modulename_load); |
| 154 |
|
| 155 |
if ($meta->{loaded}->{$package}) { |
| 156 |
return 1; |
| 157 |
} |
| 158 |
|
| 159 |
#$logger->info( __PACKAGE__ . "->load: $package" ) if $logger; |
| 160 |
#$logger->info( __PACKAGE__ . "->load: $self_modulename" ) if $logger; |
| 161 |
$logger->debug( $self_modulename . "->load: $package\t[via " . __PACKAGE__ . "]" ) if $logger; |
| 162 |
|
| 163 |
# this is the module testing phase - use mixin doesn't seem to propagate errors by default |
| 164 |
eval("use $package;"); |
| 165 |
if ($@) { |
| 166 |
$meta->{loaded}->{$package} = 0; |
| 167 |
# include caller information |
| 168 |
my @caller = caller; |
| 169 |
my $caller_msg = $caller[1] . ':' . $caller[2]; |
| 170 |
my $msg = __PACKAGE__ . "->load: $@ ($caller_msg)"; |
| 171 |
if ($logger) { |
| 172 |
$logger->error($msg); |
| 173 |
} else { |
| 174 |
print $msg, "\n"; |
| 175 |
} |
| 176 |
} |
| 177 |
|
| 178 |
#print "ref-1: ", ref $self, "\n"; |
| 179 |
#print "ref-2: ", ref $self::SUPER, "\n"; |
| 180 |
|
| 181 |
# V1: |
| 182 |
#bless $self, $package; |
| 183 |
|
| 184 |
# V2: |
| 185 |
$self->mixinPackage($package); |
| 186 |
|
| 187 |
if (my $method = $options->{method}) { |
| 188 |
$self->$method(); |
| 189 |
} |
| 190 |
|
| 191 |
return 1; |
| 192 |
|
| 193 |
} |
| 194 |
|
| 195 |
sub mixinPackage { |
| 196 |
my $self = shift; |
| 197 |
my $package = shift; |
| 198 |
|
| 199 |
# switch into foreign package and prepare for mixin |
| 200 |
$self->mixin_prepare($package); |
| 201 |
|
| 202 |
# switch into local package (scope which uses DesignPattern::Bridge) and mixin plugin-module |
| 203 |
$self->mixin_do($package); |
| 204 |
|
| 205 |
} |
| 206 |
|
| 207 |
# TODO: maybe refactor to DesignPattern::Object? what about the '$logger'? |
| 208 |
sub mixin_prepare { |
| 209 |
my $self = shift; |
| 210 |
my $package = shift; |
| 211 |
my $self_classname = ref $self; |
| 212 |
eval("package $package; use mixin::with '$self_classname';"); |
| 213 |
|
| 214 |
# FIXME: --- this is redundant --- |
| 215 |
if ($@) { |
| 216 |
$meta->{loaded}->{$package} = 0; |
| 217 |
$logger->error( __PACKAGE__ . "->load: $@" ) if $logger; |
| 218 |
} else { |
| 219 |
$meta->{loaded}->{$package} = 1; |
| 220 |
} |
| 221 |
# FIXME: --- this is redundant --- |
| 222 |
|
| 223 |
} |
| 224 |
|
| 225 |
sub mixin_do { |
| 226 |
my $self = shift; |
| 227 |
my $package = shift; |
| 228 |
# switch into foreign package and mixin plugin-module |
| 229 |
my $self_classname = ref $self; |
| 230 |
eval("package $self_classname; use mixin '$package';"); |
| 231 |
#eval("use mixin_all '$package';"); |
| 232 |
|
| 233 |
# FIXME: --- this is redundant --- |
| 234 |
if ($@) { |
| 235 |
$meta->{loaded}->{$package} = 0; |
| 236 |
$logger->error( __PACKAGE__ . "->load: $@" ) if $logger; |
| 237 |
} else { |
| 238 |
$meta->{loaded}->{$package} = 1; |
| 239 |
} |
| 240 |
# FIXME: --- this is redundant --- |
| 241 |
|
| 242 |
} |
| 243 |
|
| 244 |
sub unload { |
| 245 |
|
| 246 |
my $self = shift; |
| 247 |
my $modulename_unload = shift; |
| 248 |
|
| 249 |
my $package = $self->_getPluginPackage($modulename_unload); |
| 250 |
|
| 251 |
if ($meta->{loaded}->{$package}) { |
| 252 |
$meta->{loaded}->{$package} = 0; |
| 253 |
my $where = __PACKAGE__ . ':' . __LINE__; |
| 254 |
$logger->debug( __PACKAGE__ . "->unload: FIXME: DESTROY object is not implemented at '$where'." ) if $logger; |
| 255 |
} |
| 256 |
|
| 257 |
} |
| 258 |
|
| 259 |
|
| 260 |
sub boot { |
| 261 |
my $self = shift; |
| 262 |
$self->_abstract_function('boot'); |
| 263 |
} |
| 264 |
|
| 265 |
sub include { |
| 266 |
my $self = shift; |
| 267 |
my $includefile = shift; |
| 268 |
my $package = shift; |
| 269 |
# TODO: do better error-detection here / prevent dies under all circumstances! |
| 270 |
require $includefile; |
| 271 |
$self->mixinPackage($package) if $package; |
| 272 |
} |
| 273 |
|
| 274 |
1; |
| 275 |
__END__ |
Parent Directory
| 
Revision Log
