ch12.htm

corba比较入门级的介绍详细间接了corba访问发布各种细节。

<TT>63:         cout &lt;&lt; ex &lt;&lt; endl;</TT>
<TT>64:         return 1;</TT>
<TT>65:     }</TT>
<TT>66: </TT>
<TT>67:     // Wait for CORBA events.</TT>
<TT>68:     cout &lt;&lt; &quot;Bank \&quot;&quot; &lt;&lt; bankName &lt;&lt; &quot;\&quot; ready.&quot; &lt;&lt; endl;</TT>
<TT>69:     ::boa-&gt;impl_is_ready();</TT>
<TT>70: </TT>
<TT>71:     // When this point is reached, the application is finished.</TT>
<TT>72:     return 0;
73: }</TT> </FONT></PRE>
<P>The changes for <TT>ATMMain.cpp</TT>, similar to those in <TT>BankMain.cpp</TT>,
appear in Listing 12.3. You will readily see that the two implementations are nearly
identical.
<H4><FONT COLOR="#000077">Listing 12.3. ATMMain.cpp.</FONT></H4>
<PRE><FONT COLOR="#0066FF"><TT> 1: // ATMMain.cpp</TT>
<TT> 2: </TT>
<TT> 3: #include &quot;ATMImpl.h&quot;</TT>
<TT> 4: </TT>
<TT> 5: #include &lt;iostream.h&gt;</TT>
<TT> 6: </TT>
<B><TT> 7: #include &lt;CosNaming_c.hh&gt;</TT></B>
<TT> 8: </TT>
<TT> 9: #include &quot;../BankServer_c.h&quot;</TT>
<TT>10: </TT>
<TT>11: CORBA::BOA_var boa;</TT>
<TT>12: </TT>
<TT>13: int main(int argc, char *const *argv) {</TT>
<TT>14: </TT>
<TT>15:     // Check the number of arguments; there should be exactly one</TT>
<TT>16:     // (two counting the executable name itself).</TT>
<TT>17:     if (argc != 2) {</TT>
<TT>18:         cout &lt;&lt; &quot;Usage: ATM &lt;atmname&gt;&quot; &lt;&lt; endl;</TT>
<TT>19:         return 1;</TT>
<TT>20:     }</TT>
<TT>21: </TT>
<TT>22:     // Assign the ATM name to the first argument.</TT>
<TT>23:     const char* atmName = argv[1];</TT>
<TT>24: </TT>
<TT>25:     // Initialize the ORB and BOA.</TT>
<TT>26:     CORBA::ORB_var orb = CORBA::ORB_init(argc, argv);</TT>
<TT>27:     ::boa = orb-&gt;BOA_init(argc, argv);</TT>
<TT>28: </TT>
<TT>29:     // Create an ATM object.</TT>
<TT>30:     ATMImpl atm(atmName);</TT>
<TT>31: </TT>
<TT>32:     // Notify the BOA that the ATMImpl object is ready.</TT>
<TT>33:     ::boa-&gt;obj_is_ready(&amp;atm);</TT>
<TT>34: </TT>
<B><TT>35:     // Locate a BankServer object in the Naming Service.</TT></B>
<B><TT>36:     BankServer_var bankServer;</TT></B>
<B><TT>37:     try {</TT></B>
<B><TT>38:        CORBA::Object_ptr contextObj = orb-&gt;</TT></B>
<B><TT>39:                 resolve_initial_references(&quot;NameService&quot;);</TT></B>
<B><TT>40:         CosNaming::NamingContext_var context = CosNaming::</TT></B>
<B><TT>41:                 NamingContext::_narrow(contextObj);</TT></B>
<B><TT>42:         CosNaming::Name name;</TT></B>
<B><TT>43:         name.length(1);</TT></B>
<B><TT>44:         name[0].id = &quot;BankServer1&quot;;</TT></B>
<B><TT>45:         name[0].kind = &quot;BankServer&quot;;</TT></B>
<B><TT>46:         CORBA::Object_var object = context-&gt;resolve(name);</TT></B>
<B><TT>47:         bankServer = BankServer::_narrow(object);</TT></B>
<B><TT>48:     } catch (const CORBA::Exception&amp; ex) {</TT></B>
<B><TT>49: </TT></B>
<B><TT>50:         // The bind attempt failed...</TT></B>
<B><TT>51:         cout &lt;&lt; &quot;ATMImpl: Unable to bind to a BankServer:&quot; &lt;&lt; endl;</TT></B>
<B><TT>52:         cout &lt;&lt; ex &lt;&lt; endl;</TT></B>
<B><TT>53:         return 1;</TT></B>
<B><TT>54:     }</TT></B>
<TT>55: </TT>
<TT>56:     // Register with the BankServer.</TT>
<TT>57:     try {</TT>
<TT>58:         bankServer-&gt;registerATM(&amp;atm);</TT>
<TT>59:     } catch (const CORBA::Exception&amp; ex) {</TT>
<TT>60: </TT>
<TT>61:         // The registerATM() attempt failed...</TT>
<TT>62:         cout &lt;&lt; &quot;ATMImpl: Unable to register ATM.&quot; &lt;&lt; endl;</TT>
<TT>63:         cout &lt;&lt; ex &lt;&lt; endl;</TT>
<TT>64:         return 1;</TT>
<TT>65:     }</TT>
<TT>66: </TT>
<TT>67:     // Wait for CORBA events.</TT>
<TT>68:     cout &lt;&lt; &quot;ATM \&quot;&quot; &lt;&lt; atmName &lt;&lt; &quot;\&quot; ready.&quot; &lt;&lt; endl;</TT>
<TT>69:     ::boa-&gt;impl_is_ready();</TT>
<TT>70: </TT>
<TT>71:     // When this point is reached, the application is finished.</TT>
<TT>72:     return 0;
73: }</TT> </FONT></PRE>
<P>The modified <TT>ATMClientMain.cpp</TT>, appearing in Listing 12.4, demonstrates
similar changes. Again, the <TT>ATMClient</TT> searches the Naming Service for an
object named <TT>&quot;BankServer1&quot;</TT> of type <TT>&quot;BankServer&quot;</TT>.
The remaining code for <TT>ATMClientMain.cpp</TT> is unchanged.
<H4><FONT COLOR="#000077">Listing 12.4. ATMClientMain.cpp.</FONT></H4>
<PRE><FONT COLOR="#0066FF"><TT>  1: // ATMClientMain.cpp</TT>
<TT>  2: </TT>
<TT>  3: #include &lt;iostream.h&gt;</TT>
<TT>  4: #include &lt;stdlib.h&gt;</TT>
<TT>  5: </TT>
<TT>  6: #include &quot;../Customer/CustomerImpl.h&quot;</TT>
<TT>  7: </TT>
<B><TT>  8: #include &lt;CosNaming_c.hh&gt;</TT></B>
<TT>  9: </TT>
<TT> 10: #include &quot;../Bank_c.h&quot;</TT>
<TT> 11: #include &quot;../BankServer_c.h&quot;</TT>
<TT> 12: #include &quot;../ATM_c.h&quot;</TT>
<TT> 13: </TT>
<TT> 14: int main(int argc, char *const *argv) {</TT>
<TT> 15: </TT>
<TT> 16:     // Check the number of arguments; there should be exactly five</TT>
<TT> 17:     // (six counting the executable name itself).</TT>
<TT> 18:     if (argc != 6) {</TT>
<TT> 19:         cout &lt;&lt; &quot;Usage: ATMClient &lt;name&gt; &lt;social security number&gt;&quot;</TT>
<TT> 20:                 &quot; &lt;address&gt; &lt;mother's maiden name&gt; &lt;PIN&gt;&quot; &lt;&lt; endl;</TT>
<TT> 21:         return 1;</TT>
<TT> 22:     }</TT>
<TT> 23: </TT>
<TT> 24:     // Assign the command line arguments to the Customer attributes.</TT>
<TT> 25:     const char* name = argv[1];</TT>
<TT> 26:     const char* socialSecurityNumber = argv[2];</TT>
<TT> 27:     const char* address = argv[3];</TT>
<TT> 28:     const char* mothersMaidenName = argv[4];</TT>
<TT> 29:     CORBA::Short pin = atoi(argv[5]);</TT>
<TT> 30: </TT>
<TT> 31:     // Initialize the ORB and BOA.</TT>
<TT> 32:     CORBA::ORB_var orb = CORBA::ORB_init(argc, argv);</TT>
<TT> 33:     CORBA::BOA_var boa = orb-&gt;BOA_init(argc, argv);</TT>
<TT> 34: </TT>
<TT> 35:     // Create a Customer object.</TT>
<TT> 36:     cout &lt;&lt; &quot;ATMClient: Creating new Customer:&quot; &lt;&lt; endl;</TT>
<TT> 37:     cout &lt;&lt; &quot;  name: &quot; &lt;&lt; name &lt;&lt; endl;</TT>
<TT> 38:     cout &lt;&lt; &quot;  Social Security number: &quot; &lt;&lt; socialSecurityNumber &lt;&lt;</TT>
<TT> 39:             endl;</TT>
<TT> 40:     cout &lt;&lt; &quot;  address: &quot; &lt;&lt; address &lt;&lt; endl;</TT>
<TT> 41:     cout &lt;&lt; &quot;  mother's maiden name: &quot; &lt;&lt; mothersMaidenName &lt;&lt; endl;</TT>
<TT> 42:     CustomerImpl customer(name, socialSecurityNumber, address,</TT>
<TT> 43:             mothersMaidenName);</TT>
<TT> 44: </TT>
<TT> 45:     // Notify the BOA that the CustomerImpl object is ready.</TT>
<TT> 46:     boa-&gt;obj_is_ready(&amp;customer);</TT>
<TT> 47: </TT>
<B><TT> 48:     // Locate a BankServer object in the Naming Service,</TT></B>
<B><TT> 49:     BankServer_var bankServer;</TT></B>
<B><TT> 50:     try {</TT></B>
<B><TT> 51:         CORBA::Object_ptr contextObj = orb-&gt;</TT></B>
<B><TT> 52:                 resolve_initial_references(&quot;NameService&quot;);</TT></B>
<B><TT> 53:         CosNaming::NamingContext_var context = CosNaming::</TT></B>
<B><TT> 54:                 NamingContext::_narrow(contextObj);</TT></B>
<B><TT> 55:         CosNaming::Name name;</TT></B>
<B><TT> 56:         name.length(1);</TT></B>
<B><TT> 57:         name[0].id = &quot;BankServer1&quot;;</TT></B>
<B><TT> 58:         name[0].kind = &quot;BankServer&quot;;</TT></B>
<B><TT> 59:         CORBA::Object_var object = context-&gt;resolve(name);</TT></B>
<B><TT> 60:         bankServer = BankServer::_narrow(object);</TT></B>
<B><TT> 61:     } catch (const CORBA::Exception&amp; ex) {</TT></B>
<B><TT> 62: </TT></B>
<B><TT> 63:         // The bind attempt failed...</TT></B>
<B><TT> 64:         cout &lt;&lt; &quot;ATMClient: Unable to bind to a BankServer:&quot; &lt;&lt;</TT></B>
<B><TT> 65:                 endl;</TT></B>
<B><TT> 66:         cout &lt;&lt; ex &lt;&lt; endl;</TT></B>
<B><TT> 67:         return 1;</TT></B>
<B><TT> 68:     }</TT></B>
<TT> 69: </TT>
<TT> 70:     cout &lt;&lt; &quot;ATMClient: Successfully bound to a BankServer.&quot; &lt;&lt;</TT>
<TT> 71:             endl;</TT>
<TT> 72: </TT>
<TT> 73:     // Try to get a list of Banks and ATMs from the BankServer.</TT>
<TT> 74:     BankList_ptr banks;</TT>
<TT> 75:     ATMList_ptr ATMs;</TT>
<TT> 76: </TT>
<TT> 77:     try {</TT>
<TT> 78:         banks = bankServer-&gt;getBanks();</TT>
<TT> 79:         ATMs = bankServer-&gt;getATMs();</TT>
<TT> 80:     } catch (const CORBA::Exception&amp; ex) {</TT>
<TT> 81: </TT>
<TT> 82:         // The attempt failed...</TT>
<TT> 83:         cout &lt;&lt; &quot;ATMClient: Unable to get lists of Banks and ATMs:&quot;</TT>
<TT> 84:                 &lt;&lt; endl;</TT>
<TT> 85:         cout &lt;&lt; ex &lt;&lt; endl;</TT>
<TT> 86:         return 1;</TT>
<TT> 87:     }</TT>
<TT> 88: </TT>
<TT> 89:     // Use the first Bank and the first ATM that appear in the</TT>
<TT> 90:     // lists.</TT>
<TT> 91:     if (banks-&gt;length() == 0) {</TT>
<TT> 92: </TT>
<TT> 93:         // No Banks were available.</TT>
<TT> 94:         cout &lt;&lt; &quot;ATMClient: No Banks available.&quot; &lt;&lt; endl;</TT>
<TT> 95:         return 1;</TT>
<TT> 96:     }</TT>
<TT> 97:     if (ATMs-&gt;length() == 0) {</TT>
<TT> 98: </TT>
<TT> 99:         // No ATMs were available.</TT>
<TT>100:         cout &lt;&lt; &quot;ATMClient: No ATMs available.&quot; &lt;&lt; endl;</TT>
<TT>101:         return 1;</TT>
<TT>102:     }</TT>
<TT>103:     Bank_var bank = (*banks)[0];</TT>
<TT>104:     ATM_var atm = (*ATMs)[0];</TT>
<TT>105:     cout &lt;&lt; &quot;ATMClient: Using Bank \&quot;&quot; &lt;&lt; bank-&gt;name() &lt;&lt; &quot;\&quot; and&quot;</TT>
<TT>106:             &lt;&lt; &quot; ATM \&quot;&quot; &lt;&lt; atm-&gt;name() &lt;&lt; &quot;\&quot;.&quot; &lt;&lt; endl;</TT>
<TT>107: </TT>
<TT>108:     // Do some cool stuff.</TT>
<TT>109: </TT>
<TT>110:     Account_var account;</TT>
<TT>111:     ATMCard_var atmCard;</TT>
<TT>112: </TT>
<TT>113:     try {</TT>
<TT>114:         account = bank-&gt;createAccount(&amp;customer, &quot;checking&quot;, 0.0);</TT>
<TT>115:     } catch (const CORBA::Exception&amp; ex) {</TT>
<TT>116: </TT>
<TT>117:         // The createAccount() attempt failed...</TT>
<TT>118:         cout &lt;&lt; &quot;ATMClient: Unable to create Account.&quot; &lt;&lt; endl;</TT>
<TT>119:         cout &lt;&lt; ex &lt;&lt; endl;</TT>
<TT>120:         return 1;</TT>
<TT>121:     }</TT>
<TT>122: </TT>
<TT>123:     try {</TT>
<TT>124: </TT>
<TT>125:         // Request the automatic account update service from the</TT>
<TT>126:         // Bank.</TT>
<TT>127:         bank-&gt;requestUpdateService(account);</TT>
<TT>128:     } catch (const CORBA::Exception&amp; ex) {</TT>
<TT>129: </TT>
<TT>130:         // The requestUpdateService() attempt failed...</TT>
<TT>131:         cout &lt;&lt; &quot;ATMClient: Unable to create Account.&quot; &lt;&lt; endl;</TT>
<TT>132:         cout &lt;&lt; ex &lt;&lt; endl;</TT>
<TT>133:         return 1;</TT>
<TT>134:     }</TT>
<TT>135: </TT>
<TT>136:     try {</TT>
<TT>137: </TT>
<TT>138:         // Print out some Account statistics.</TT>
<TT>139:         cout &lt;&lt; &quot;ATMClient: Opened new Account:&quot; &lt;&lt; endl;</TT>
<TT>140:         cout &lt;&lt; &quot;  account number: &quot; &lt;&lt; account-&gt;accountNumber() &lt;&lt;</TT>
<TT>141:                 endl;</TT>
<TT>142:         cout &lt;&lt; &quot;  creation date: &quot; &lt;&lt; account-&gt;creationDate() &lt;&lt;</TT>