javamanager/javainstaller/installer/javasrc.s60/com/nokia/mj/impl/installer/utils/PropertyProvider.java
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/javamanager/javainstaller/installer/javasrc.s60/com/nokia/mj/impl/installer/utils/PropertyProvider.java Fri Jul 23 12:27:20 2010 +0300
@@ -0,0 +1,179 @@
+/*
+* Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description:
+*
+*/
+
+
+package com.nokia.mj.impl.installer.utils;
+
+/**
+ * Provides notifications whenever the subscribed property value changes.
+ * <br>
+ * One PropertyProvider instance can be used to subscribe events
+ * for only one property. If events for more properties are needed
+ * use separate PropertyProvider instance for each property.
+ *
+ * @see PropertyListener
+ */
+public class PropertyProvider
+{
+ /** Property category. */
+ private int iCategory = 0;
+ /** Property key. */
+ private int iKey = 0;
+ /** Property listener. */
+ private PropertyListener iListener = null;
+ /** Handle to native object. */
+ private int iHandle = 0;
+
+ /**
+ * Constructor.
+ */
+ public PropertyProvider()
+ {
+ }
+
+ /**
+ * Subscribe to listen changes of specified property value.
+ * One PropertyListener can subscribe to only one property
+ * value at a time.
+ *
+ * @param aCategory property category
+ * @param aKey property key
+ * @param aListener listener to be notified.
+ */
+ public void subscribe(int aCategory, int aKey, PropertyListener aListener)
+ {
+ if (iHandle != 0)
+ {
+ InstallerException.internalError("PropertyProvider already in use.");
+ }
+ iCategory = aCategory;
+ iKey = aKey;
+ iListener = aListener;
+ // Start a new thread which blocks until unsubscribe is called.
+ final PropertyProvider provider = this;
+ new Thread(new Runnable()
+ {
+ public void run()
+ {
+ synchronized (provider)
+ {
+ iHandle = _subscribe(iCategory, iKey);
+ // Notify subscribe method after subscription
+ // result is available.
+ provider.notify();
+ }
+ if (iHandle > 0)
+ {
+ // Subscription succeeded, start to process events.
+ _processEvents(iHandle, provider);
+ }
+ }
+ }, "PropertyProviderThread").start();
+ synchronized (this)
+ {
+ try
+ {
+ if (iHandle == 0)
+ {
+ // Wait until subscription has been completed.
+ wait();
+ }
+ }
+ catch (InterruptedException ie)
+ {
+ }
+ }
+ // Check if subscription failed.
+ if (iHandle < 0)
+ {
+ Log.logError("PropertyProvider.subscribe failed with code " + iHandle);
+ iHandle = 0;
+ }
+ }
+
+ /**
+ * Unubscribe from listening changes.
+ */
+ public void unsubscribe()
+ {
+ final PropertyProvider provider = this;
+ new Thread(new Runnable()
+ {
+ public void run()
+ {
+ synchronized (provider)
+ {
+ if (iHandle <= 0)
+ {
+ Log.logWarning(
+ "PropertyProvider.unsubscribe: no subscription.");
+ return;
+ }
+ int err = _unsubscribe(iHandle);
+ if (err < 0)
+ {
+ Log.logError(
+ "PropertyProvider.unsubscribe failed with code " +
+ err);
+ }
+ else
+ {
+ iHandle = 0;
+ }
+ }
+ }
+ }, "PropertyProviderUnsubscribeThread").start();
+ }
+
+ /**
+ * Called from native when value for the subscribed property changes.
+ */
+ private void valueChanged(int aValue)
+ {
+ if (iListener != null)
+ {
+ iListener.valueChanged(iCategory, iKey, aValue);
+ }
+ }
+
+ /**
+ * Subscribe to listen changes of specified property value.
+ *
+ * @param aCategory property category
+ * @param aKey property key
+ * @return handle to native side object or Symbian error
+ * code (negative number)
+ */
+ private static native int _subscribe(int aCategory, int aKey);
+
+ /**
+ * Starts to process events. This call blocks until unsubscribe is called.
+ *
+ * @param aHandle handle to native side object
+ * @param aProvider PropertyProvider class instance to be notified
+ * @return 0 or Symbian error code (negative number)
+ */
+ private static native int _processEvents(int aHandle, PropertyProvider aProvider);
+
+ /**
+ * Unubscribe from listening changes.
+ *
+ * @param aHandle handle to native side object
+ * @return 0 or Symbian error code (negative number)
+ */
+ private static native int _unsubscribe(int aHandle);
+}