Java实验: 基于CORBA的分布式议程服务 (2)
1.1 关键代码
绑定远程对象：
public static void main(String[] args) {
try {
// 8步 ： 初始化---根---策略----子POA---伺服---激活---激活---监听
//初始化
org.omg.CORBA.ORB orb=org.omg.CORBA.ORB.init(args, null);
//根
org.omg.PortableServer.POA rootPOA=
POAHelper.narrow(orb.resolve_initial_references("RootPOA"));
//策略
org.omg.CORBA.Policy[] policies=
{rootPOA.create_lifespan_policy(
LifespanPolicyValue.PERSISTENT)};
//有 根和策略 创建子POA
org.omg.PortableServer.POA agendaPOA=
rootPOA.create_POA("AgendaPOA",
rootPOA.the_POAManager(), policies);
//伺服
AgendaCORBAImpl agendaServant=new AgendaCORBAImpl();
//激活 伺服
agendaPOA.activate_object_with_id(
"AgendaManager".getBytes(), agendaServant);
//激活 POA管理器
rootPOA.the_POAManager().activate();
System.out.println("Server has ready ...");
//循环监听
orb.run();
} catch (Exception e) {
e.printStackTrace();
}
}
获取远程对象
private static IAgenda getAgenda(String[] args) {
try {
//初始化
org.omg.CORBA.ORB orb=org.omg.CORBA.ORB.init(args,null);
//查找
IAgenda agenda=
IAgendaHelper.bind(
orb,"/AgendaPOA","AgendaManager".getBytes());
return agenda;
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
获取数据库连接：
DBConnectionFacade.java
/**
* Gets the database connection from current active connection provider.
* @return the connection
*/
public static Connection getConnection() throws DBConnectionException{
if (connProvider==null) {
synchronized (initLock) {
if (connProvider==null) { resourceBundleUtil=
ResourceBundleUtil.getResourceBundleUtil(Lables);
String providerClassName=
resourceBundleUtil.getString("provider.calss");
if (providerClassName!=null
&&providerClassName.length()==0) {
try {
Class providerClass=
Class.forName(providerClassName);
connProvider=(DBConnectionProvider)
providerClass.newInstance();//动态装载
} catch (Exception e) {}//这里删去处理异常的代码
}
else {
connProvider = new DBConnectionDefaultPool(resourceBundleUtil);
}
connProvider.initProvider();
}
}
}
return Connection conn=connProvider.getConnection();//这里删去处理异常的代码
}
接口DBConnectionProvider的默认实现类DBConnectionDefaultPool.java
/**
* initial the connection pool.
*
* @see Database.DBConnectionProvider#initProvider()
*/
public void initProvider() throws DBConnectionException {
// set Lock to prevent a connection be returned.
synchronized (initLock) {
// Get properties
String driver = resourceBundleUtil.getString("driver");
String server = resourceBundleUtil.getString("server");
String username = resourceBundleUtil.getString("username");
String password = resourceBundleUtil.getString("password");
// System.out.println(driver+ server+ username+password);
int minConnections = 0, maxConnections = 0;
double connectionTimeOut = 0.0;
try {
minConnections = Integer.parseInt(resourceBundleUtil.getString("minConnections"));
maxConnections = Integer.parseInt(resourceBundleUtil
.getString("maxConnections"));
connectionTimeOut = Double.parseDouble(resourceBundleUtil
.getString("connectionTimeOut"));
} catch (Exception e) {
throw new ResourceBundleNotFoundException(
"Could not parse default pool properties. "
+ "Make sure the values exist and are correct.",
e);
}
String logPath = resourceBundleUtil.getString("logPath");
try {
connectionPool = new ConnectionPool(driver, server, username,
password, minConnections, maxConnections, logPath,
connectionTimeOut);
} catch (IOException e) {
// "Error starting DbConnectionDefaultPool: "
// throw new ConnectionPoolInitPool("Cannt found properties");
e.printStackTrace();
}
}
}
public Connection getConnection() throws DBConnectionException {
if (connectionPool == null) {
// Block until the init has been done.
synchronized (initLock) {// waitting for init.
if (connectionPool == null) {
// Something has gone wrong.
return null;
}