本文主要内容涉及:
- CORBA基本架构
- IDL文件编写
- POA示例实现
- POA+TIE示例实现
- ImplBase示例实现
- ImplBase+TIE示例实现
- Persistent示例实现
ImplBase主要是为了兼容旧代码所提供的,正常情况下,大家是不需要使用的。
JDK提供了工具,可以直接生成stubs及skeletons接口代码:
idlj -fall -oldImplBase Hi.idl
编写server端代码:
import HiCorba.*; import org.omg.CosNaming.*; import org.omg.CosNaming.NamingContextPackage.*; import org.omg.CORBA.*; import java.util.Properties; class HiImpl extends _HiImplBase{ private ORB orb; public void setORB(ORB orb_val){ orb = orb_val; } // implement sayHiTo() method public String sayHiTo(String someone) { return "\nHi, "+someone+" !"+"\n"; } // implement add() method public int add(int numa, int numb) { return numa+numb; } // implement shutdown() method public void shutdown() { orb.shutdown(false); } } public class HiServer { public static void main(String args[]) { try{ // create and initialize the ORB ORB orb = ORB.init(args, null); // create servant and register it with the ORB HiImpl hiImpl = new HiImpl(); hiImpl.setORB(orb); // get the root naming context org.omg.CORBA.Object objRef = orb.resolve_initial_references("NameService"); NamingContext ncRef = NamingContextHelper.narrow(objRef); Hi href = HiHelper.narrow(hiImpl); // bind the Object Reference in Naming NameComponent nc = new NameComponent("Hi", ""); NameComponent path[] = {nc}; ncRef.rebind(path, href); System.out.println("HiServer ready and waiting ..."); // wait for invocations from clients orb.run(); } catch (Exception e) { System.err.println("ERROR: " + e); e.printStackTrace(System.out); } System.out.println("HiServer Exiting ..."); } }
编写client端代码:
import HiCorba.*; import org.omg.CosNaming.*; import org.omg.CosNaming.NamingContextPackage.*; import org.omg.CORBA.*; public class HiClient{ public static void main(String args[]){ try{ // create and initialize the ORB ORB orb = ORB.init(args, null); // get the root naming context org.omg.CORBA.Object objRef = orb.resolve_initial_references("NameService"); NamingContext ncRef = NamingContextHelper.narrow(objRef); // resolve the Object Reference in Naming NameComponent nc = new NameComponent("Hi", ""); NameComponent path[] = {nc}; Hi hiImpl = HiHelper.narrow(ncRef.resolve(path)); System.out.println("Obtained a handle on server object: " + hiImpl); System.out.println(hiImpl.sayHiTo("neohope")); System.out.println(hiImpl.add(70, 80)); hiImpl.shutdown(); } catch (Exception e) { System.out.println("ERROR : " + e) ; e.printStackTrace(System.out); } } }
编译代码:
javac *.java HiCorba/*.java
测试,在三个shell或cmd窗口中依次运行:
#shell01 orbd -ORBInitialPort 1900
#shell02 java HiServer -ORBInitialPort 1900 >>HiServer ready and waiting ... >>HiServer Exiting ...
#shell03 java HiClient -ORBInitialPort 1900 -ORBInitialHost localhost >>Obtained a handle on server object: IOR:000000000000001349444c3a4869436f7262612f 48693a312e30000000000001000000000000006e000102000000000d3139322e3136382e35362e31 000074c300000019afabcb0000000002768712000000000800000001000000001400000000000002 00000001000000200000000000010001000000020501000100010020000101090000000100010100 00000026000000020002 >>Hi, neohope ! >>150