要让JAVA程序能访问SAP系统,一般通过SAP JCO接口进行通讯,在获取到SAP的连接时需求提供一些连接参数,这些参数在最新的 JCO 3.0 中需要被保存到一个带有扩展名.jcoDestination的文件中,这个文件同时被保存在应用程序的安装目录中。因为这只中一个纯文本文件,所有的连接参数并没有被加密,这样对于公用程序可能有安全问题。要使用登陆连接更加安全可以实现自定义的 DestinationDataProvider 实现:
此接口只有简单的三个方法:

interface DestinationDataProvider {
Properties getDestinationProperties(java.lang.String destinationName);
void setDestinationDataEventListener(DestinationDataEventListener eventListener);
boolean supportsEvents();
}

getDestinationProperties 当Java程序获取到SAP的连接时,jco会从这里读取连接属性,你可以编程动态的设定这些属性
setDestinationDataEventListener 设置一个连接事件监听器,实现一个监听器,当JCO连接SAP以获得通知
supportsEvents 返回是否被实现的DestinationDataProvider有事件监听器

实现一个自定义Provider:

    static class MyDestinationDataProvider implements DestinationDataProvider
{
private DestinationDataEventListener eL; private Properties ABAP_AS_properties; public Properties getDestinationProperties(String destinationName)
{
if(destinationName.equals("ABAP_AS") && ABAP_AS_properties!=null)
return ABAP_AS_properties; return null;
//alternatively throw runtime exception
//throw new RuntimeException("Destination " + destinationName + " is not available");
} public void setDestinationDataEventListener(DestinationDataEventListener eventListener)
{
this.eL = eventListener;
} public boolean supportsEvents()
{
return true;
} void changePropertiesForABAP_AS(Properties properties)
{
if(properties==null)
{
eL.deleted("ABAP_AS");
ABAP_AS_properties = null;
}
else
{
if(ABAP_AS_properties!=null && !ABAP_AS_properties.equals(properties))
eL.updated("ABAP_AS");
ABAP_AS_properties = properties;
}
}
}

测试连接:

    public static void main(String[] args) throws Exception
{
Properties connectProperties = new Properties();
connectProperties.setProperty(DestinationDataProvider.JCO_ASHOST, "binmain");
connectProperties.setProperty(DestinationDataProvider.JCO_SYSNR, "53");
connectProperties.setProperty(DestinationDataProvider.JCO_CLIENT, "000");
connectProperties.setProperty(DestinationDataProvider.JCO_USER, "JCOTEST");
connectProperties.setProperty(DestinationDataProvider.JCO_PASSWD, "JCOTEST");
connectProperties.setProperty(DestinationDataProvider.JCO_LANG, "en"); MyDestinationDataProvider myProvider = new MyDestinationDataProvider(); com.sap.conn.jco.ext.Environment.registerDestinationDataProvider(myProvider);
myProvider.changePropertiesForABAP_AS(connectProperties); JCoDestination ABAP_AS = JCoDestinationManager.getDestination("ABAP_AS");
ABAP_AS.ping(); System.out.println("ABAP_AS destination is ok"); }
05-11 13:24