xmlblasteraccessrawbase.java

java开源的企业总线.xmlBlaster

package org.xmlBlaster.client.protocol.http.common;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.util.Hashtable;
import java.util.Enumeration;
import java.util.Vector;

/**
 * A java client implementation to access xmlBlaster using a persistent http connection
 * for instant callback messages. 
 * <p>
 * You can control logging with the Applet PARAM tag, logging output is put to the Java console
 * of your browser:
 * </p>
 * <pre>
 * &lt;PARAM name="xmlBlaster/logLevels" value="ERROR,WARN">
 * with more logging:
 * &lt;PARAM name="xmlBlaster/logLevels" value="ERROR,WARN,INFO,DEBUG">
 * </pre>
 * See the example applet {@link http.applet.HelloWorld3} on how to use it.
 * @author <a href="mailto:[e-mail]">Marcel Ruff</a>
 * @see http.applet.HelloWorld3
 */
public abstract class XmlBlasterAccessRawBase implements I_XmlBlasterAccessRaw
{
   /** Typically "http://localhost:8080/xmlBlaster/AppletServlet" */
   protected String xmlBlasterServletUrl;
   private PersistentRequest persistentHttpConnection;
   private I_CallbackRaw callback;
   public static final boolean ONEWAY = true;
   private boolean isConnected = false;
   protected Hashtable properties = new Hashtable();
   protected I_Log logListener;
   protected String logLevels = "ERROR,WARN,INFO";
   private Hashtable cookie;
   private static int staticInstanceCounter;
   protected int instanceCount;

   private static Object mutexer = new Object();

   /**
    * Provides access to xmlBlaster server. 
    * @see #parseAppletParameter
    * @param properties "xmlBlaster/servletUrl", "xmlBlaster/logLevels" (locally used)
    * and additional properties which are send to the servlet.<br />
    * The addtional properties must start with "servlet/xyz=someValue". The "servlet/" will
    * be stripped away and in the web-servlet will arrive "xyz=someValue".
    * The key/values are send in the URL. 
    */
   public XmlBlasterAccessRawBase(Hashtable properties) {
      synchronized (mutexer) {
         staticInstanceCounter++;
         this.instanceCount = staticInstanceCounter;
      }
      this.properties = properties;
      this.xmlBlasterServletUrl = (String)this.properties.get("xmlBlaster/servletUrl"); //param from html page
      if (this.properties.get("xmlBlaster/logLevels") != null)
         logLevels = (String)this.properties.get("xmlBlaster/logLevels");
      log("DEBUG", new StringBuffer("constructor - ").append(getXmlBlasterServletUrl()).toString());
   }

   public String getInstanceId() {
      return ""+getInstanceCount();
   }

   /**
    * Access the unique counter of this object instance. 
    */
   public int getInstanceCount() {
      return this.instanceCount;
   }

   /**
    * Register to receive the logging output
    * @param listener If null we log to the java console of the browser
    */
   public synchronized void setLogListener(I_Log logListener) {
      this.logListener = logListener;

   }
   
   /**
    * @see I_XmlBlasterAccessRaw#getHtmlProperties
    */
   public Hashtable getHtmlProperties() {
      return this.properties;
   }

   /**
    * Log to java console of the browser of the logListener if any is registered
    */
   protected void log(String level, String text) {
      log("XmlBlasterAccess", level, text);
   }

   /**
    * @see I_XmlBlasterAccessRaw#log(String, String, String)
    */
   public synchronized void log(String location, String level, String text) {
      if (this.logListener != null) {
         this.logListener.log(location, level, text);
      }
      if (logLevels.indexOf(level) != -1) System.out.println(new StringBuffer(location).append(" #").append(this.instanceCount).append(" [").append(level).append("]: ").append(text).toString());
   }

   /** 
    * Access the URL of the xmlBlaster servlet. 
    * @return Typically "http://localhost:8080/xmlBlaster/AppletServlet&appletInstanceCount=1"
    */
   public String getXmlBlasterServletUrl() {
      String url = this.xmlBlasterServletUrl;
      if (url != null) {
         StringBuffer tmp = new StringBuffer();
         if (url.indexOf("?") >= 0) 
            tmp.append(url).append("&appletInstanceCount=").append(this.instanceCount);
         else
            tmp.append(url).append("?appletInstanceCount=").append(this.instanceCount);
         
         // Add additional paramaters and send to the servlet
         Hashtable props = getHtmlProperties();
         Enumeration it = props.keys();
         while (it.hasMoreElements()) {
            String key = (String)it.nextElement();
            String value = (String)props.get(key);
            if (key.startsWith("servlet/")) {
               key = key.substring("servlet/".length());
               tmp.append("&").append(key).append("=").append(value);
            }
         }
         
         url = tmp.toString();
      }
      log("DEBUG", new StringBuffer("URL=").append(url).toString());
      return url;
   }

   public void isConnected(boolean isConnected) {
      this.isConnected = isConnected;
      log("INFO", new StringBuffer("isConnected(").append(isConnected).append(")").toString());
   }

   public boolean isConnected() {
      return this.isConnected;
   }

   private String startPersistentHttpConnection() throws Exception {
      this.persistentHttpConnection.start();
      log("DEBUG", "Waiting for connect() to establish ...");

      int num = 100;
      int i;
      for (i=0; i<num; i++) {
         if (this.isConnected) {
            break;
         }
         try {
            Thread.sleep(500);
         } catch(java.lang.InterruptedException e){
            log("WARN", e.toString());
         }
      }
      if (i >= num) {
         log("ERROR", "Can't login to xmlBlaster, timed out.");
         throw new Exception("Can't login to xmlBlaster, timed out.");
      }
      log("INFO", new StringBuffer("Successfully connected to xmlBlaster '").append(getXmlBlasterServletUrl()).append("'").toString());
      return this.persistentHttpConnection.getConnectReturnQos();
   }

   /**
    * @see I_XmlBlasterAccessRaw#connect(String, I_CallbackRaw)
    */
   public String connect(String qos, I_CallbackRaw callback) throws Exception {
      this.callback = callback;

      // We pass getHtmlProperties() to the servlet to be used to initialize Global
      // currently this is attached to the URL (not very nice)
      
      if (qos == null) {
         String loginName = (String)this.properties.get("xmlBlaster/loginName");
         String passwd = (String)this.properties.get("xmlBlaster/passwd");
         if (loginName != null && passwd != null) {
            log("INFO", new StringBuffer("Using loginName = ").append(loginName).append(" as configured in your HTML page to connect to xmlBlaster").toString());
            this.persistentHttpConnection = new PersistentRequest(this, getXmlBlasterServletUrl(), loginName, passwd);
         }
         else
            qos = "<qos/>"; // Servlet does authentication (can be a security issue!)
      }

      if (qos != null) {
         this.persistentHttpConnection = new PersistentRequest(this, getXmlBlasterServletUrl(), qos);
      }

      return startPersistentHttpConnection();
   }

   /**
    * @see I_XmlBlasterAccessRaw#connect(String, I_CallbackRaw)
    */
   public String sendXmlScript(String xmlRequest) throws Exception {
      log("DEBUG", new StringBuffer("xmlScript(xmlRequest=").append(xmlRequest).append(")").toString());
      return (String)postRequest("xmlScript", xmlRequest, null, null, !ONEWAY);
   }

   public Hashtable ping(java.lang.String qos) throws Exception {
      log("DEBUG", new StringBuffer("ping(qos=").append(qos).append(")").toString());
      return (Hashtable)postRequest(PING_NAME, null, qos, null, !ONEWAY);
   }

   public Hashtable subscribe(java.lang.String xmlKey, java.lang.String qos) throws Exception {
      log("DEBUG", new StringBuffer("subscribe(key=").append(xmlKey).append(")").toString());
      return (Hashtable)postRequest(SUBSCRIBE_NAME, xmlKey, qos, null, !ONEWAY);
   }

   public Msg[] get(java.lang.String xmlKey, java.lang.String qos) throws Exception {
      log("DEBUG", new StringBuffer("get(key=").append(xmlKey).append(")").toString());
      //String keyEnc = encode(xmlKey, "UTF-8");
      //String qosEnc = encode(qos, "UTF-8");
      Vector list = (Vector)postRequest(GET_NAME, xmlKey, qos, null, !ONEWAY);
      Msg[] msgs = new Msg[list.size()/3];
      for (int i=0; i<list.size()/3; i++) {
         log("DEBUG", "Synchronous get is not implented");
         Hashtable qosRet = (Hashtable)list.elementAt(i*3);
         Hashtable keyRet = (Hashtable)list.elementAt(i*3+1);
         byte[] content = (byte[])list.elementAt(i*3+2);
         msgs[i] = new Msg(keyRet, content, qosRet);
      }
      return msgs;
   }

   public Hashtable[] unSubscribe(java.lang.String xmlKey, java.lang.String qos) throws Exception {
      log("DEBUG", new StringBuffer("unSubscribe(key=").append(xmlKey).append(")").toString());
      return (Hashtable[])postRequest(UNSUBSCRIBE_NAME, xmlKey, qos, null, !ONEWAY);
   }

   public Hashtable publish(String xmlKey, byte[] content, String qos) throws Exception {
      log("DEBUG", new StringBuffer("publish(key=").append(xmlKey).append(")").toString());
      return (Hashtable)postRequest(PUBLISH_NAME, xmlKey, qos, content, !ONEWAY);
   }

   public Hashtable[] erase(java.lang.String xmlKey, java.lang.String qos) throws Exception {
      log("DEBUG", new StringBuffer("erase(key=").append(xmlKey).append(")").toString());
      return (Hashtable[])postRequest(ERASE_NAME, xmlKey, qos, null, !ONEWAY);
   }

   public void disconnect(String qos) {
      log("DEBUG", "disconnect()");
      try {
         postRequest("disconnect", null, qos, null, !ONEWAY);
         log("INFO", "Successfully disconnected from xmlBlaster");
      }
      catch (Exception e) {
         log("WARN", new StringBuffer("Ignoring unexpected exception during disconnect: ").append(e.toString()).toString());
      }
   }
   
   /**
    * The format:
    * oid + \0 + key + '\0' + qos + '\0' + content: length = oid + key + qos + content + 3
    * @param conn
    * @param actionType
    * @param key
    * @param qos
    * @param content
    */
   static void writeRequest(I_Connection conn, String actionType, String key, String qos, byte[] content) throws IOException {
      conn.setRequestProperty("ActionType", actionType);
      conn.setRequestProperty("BinaryProtocol", "true");
      int length = ObjectOutputStreamMicro.getMessageLength(null, key, qos, content);
      // this is needed since J2ME does not set Content-Length (don't know why)
      conn.setRequestProperty("Data-Length", String.valueOf(length));
      ObjectOutputStreamMicro.writeMessage(conn.getOutputStream(), null, key, qos, content);
      //conn.getOutputStream().close();
   }


   /**
    * Send a http request to the servlet. 
    * @param request The request string without the URL prefix, e.g. "?XmlBlasterAccessRawType=pong"
    * @param doPost if true POST else GET
    * @param oneway true for requests returning void
    * @return The returned value for the given request, "" on error or for oneway messages
    */
   /*
   Object postRequestOld(String actionType, String key, String qos, byte[] content, boolean oneway) throws Exception {
      String request = "ActionType=" + actionType;
      try {
         boolean doPost = true;
         // applet.getAppletContext().showDocument(URL url, String target);
         //String url = (doPost) ? this.xmlBlasterServletUrl : this.xmlBlasterServletUrl + request;

         if ("xmlScript".equals(actionType)) {
            if (key != null) request += "&xmlRequest=" + encode(key, "UTF-8");
         }
         else {
            if (key != null) request += "&key=" + encode(key, "UTF-8");
            if (qos != null) request += "&qos=" + encode(qos, "UTF-8");
            if (content != null) request += "&content=" + encode(new String(content), "UTF-8");
         }