[webMethods] 如何在 Java Service 中呼叫另外一個 Java Service

Problem
假設我有兩個 Java Service，一個為 Test Java Service: input 參數為 name，執行時會出現 popup window 供輸入


另外一個為 HelloWorld，input parameters 有兩個，分別是 name 與 dateTime，由Test Java Service 傳送給 HellowWorld Java Service，welcomeMessage = name + "(" + dateTime + ")"



How-to
可以使用 Service.doInvoke 來呼叫其他 Service
以下是 Test Service 中的 code snippet:

public final class Test_SVC

{

    /** 
     * The primary method for the Java service
     *
     * @param pipeline
     *            The IData pipeline
     * @throws ServiceException
     */
    public static final void Test(IData pipeline) throws ServiceException {
        IDataCursor pipelineCursor = pipeline.getCursor();
        
        // Invoke the pub.date:getCurrentDateString service to get current date time
        String currentDateString = "";
        IDataUtil.put(pipelineCursor, "pattern", "yyyy/MM/dd HH:mm:ss");
        try {
            IData data = Service.doInvoke("pub.date", "getCurrentDateString", pipeline);
            currentDateString = (String) IDataUtil.get(data.getCursor(), "value");
        } catch (Exception e) {
            throw new ServiceException(e);
        }
        
        // input name
        String name = IDataUtil.getString(pipelineCursor, "name");
        IDataUtil.put(pipelineCursor, "name", name);
        
        // get current date time via pub.date:getCurrentDateString service
        IDataUtil.put(pipelineCursor, "dateTime", currentDateString);
        
        // Invoke HelloWorld service
        try {
            Service.doInvoke("acme.albert.work", "HelloWorld", pipeline);
        } catch (Exception e) {
            throw new ServiceException(e);
        }
        
        pipelineCursor.destroy();
    }
}    

以下是 HelloWorld Service 中的 code snippet:

public final class HelloWorld_SVC

{

    /** 
     * The primary method for the Java service
     *
     * @param pipeline
     *            The IData pipeline
     * @throws ServiceException
     */
    public static final void HelloWorld(IData pipeline) throws ServiceException {
        // pipeline
        IDataCursor pipelineCursor = pipeline.getCursor();
        String name = IDataUtil.getString(pipelineCursor, "name");
        String dateTime = IDataUtil.getString(pipelineCursor, "dateTime");
        logger("dateTime = " + dateTime);
        
        pipelineCursor.destroy();
                
        // pipeline
        IDataCursor pipelineCursor_1 = pipeline.getCursor();
        String welcomeMsg = "Hello~" + name + " (" + dateTime + ")";
        logger("welcome msg = " + welcomeMsg);
        IDataUtil.put( pipelineCursor_1, "welcomeMessage", welcomeMsg );
        pipelineCursor_1.destroy();     
    }
    
    // --- <<IS-BEGIN-SHARED-SOURCE-AREA>> ---  
    public static void logger(String message) throws ServiceException {
        IData input = IDataFactory.create();
        
        IDataCursor inputCursor = input.getCursor();
        IDataUtil.put(inputCursor, "message", message);
        IDataUtil.put(inputCursor, "function", "customLogger");
        IDataUtil.put(inputCursor, "level", "INFO");
        inputCursor.destroy();
    
        try {
            Service.doInvoke("pub.flow", "debugLog", input);
        } catch (Exception e) {
            throw new ServiceException(e);
        }
    }
    
    // --- <<IS-END-SHARED-SOURCE-AREA>> ---

}

執行結果:

[9987]2016-11-16 15:52:31 TST [ISP.0090.0004I] customLogger -- welcome msg = Hello~Albert (2016/11/16 15:52:31)
[9986]2016-11-16 15:52:31 TST [ISP.0090.0004I] customLogger -- dateTime = 2016/11/16 15:52:31

上述的範例是採取 synchronous 的方式去呼叫另外一個 Java Service，若要採用 asynchronous 的方式呼叫，需要改寫如下：

    Session session = Service.getSession();
    
    IData input = IDataFactory.create();
    IDataCursor inputCursor = input.getCursor();
    IDataUtil.put(inputCursor, "input", "hello");
    inputCursor.destroy();
    
    Service.doThreadInvoke("acme.albert.work.OPC", "OPC_Heartbeat_Flow", session, input);