1 files changed, 308 insertions, 0 deletions
diff --git a/sca-java-2.x/tags/2.0.1-RC1/modules/sca-api/src/main/java/org/oasisopen/sca/client/impl/SCAClientFactoryFinderImpl.java b/sca-java-2.x/tags/2.0.1-RC1/modules/sca-api/src/main/java/org/oasisopen/sca/client/impl/SCAClientFactoryFinderImpl.java
new file mode 100644
index 0000000000..14a02c8b8f
--- /dev/null
+++ b/sca-java-2.x/tags/2.0.1-RC1/modules/sca-api/src/main/java/org/oasisopen/sca/client/impl/SCAClientFactoryFinderImpl.java
@@ -0,0 +1,308 @@
+/*
+ * Copyright(C) OASIS(R) 2005,2010. All Rights Reserved.
+ * OASIS trademark, IPR and other policies apply.
+ */
+package org.oasisopen.sca.client.impl;
+
+import org.oasisopen.sca.client.SCAClientFactoryFinder;
+
+import java.io.BufferedReader;
+import java.io.Closeable;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.lang.reflect.Constructor;
+import java.net.URI;
+import java.net.URL;
+import java.security.AccessController;
+import java.security.PrivilegedAction;
+import java.util.Properties;
+
+import org.oasisopen.sca.NoSuchDomainException;
+import org.oasisopen.sca.ServiceRuntimeException;
+import org.oasisopen.sca.client.SCAClientFactory;
+
+/**
+ * This is a default implementation of an SCAClientFactoryFinder which is 
+ * used to find an implementation of the SCAClientFactory interface.
+ * 
+ * @see SCAClientFactoryFinder
+ * @see SCAClientFactory
+ * 
+ * @author OASIS Open
+ */
+public class SCAClientFactoryFinderImpl implements SCAClientFactoryFinder {
+
+    /**
+     * The name of the System Property used to determine the SPI 
+     * implementation to use for the SCAClientFactory.
+     */
+    private static final String SCA_CLIENT_FACTORY_PROVIDER_KEY = 
+    	SCAClientFactory.class.getName();
+
+    /**
+     * The name of the file loaded from the ClassPath to determine 
+     * the SPI implementation to use for the SCAClientFactory.
+     */
+    private static final String SCA_CLIENT_FACTORY_PROVIDER_META_INF_SERVICE 
+        = "META-INF/services/" + SCA_CLIENT_FACTORY_PROVIDER_KEY;
+
+    /**
+     * Public Constructor
+     */
+    public SCAClientFactoryFinderImpl() {
+    }
+    
+    /**
+     * Creates an instance of the SCAClientFactorySPI implementation. 
+     * This discovers the SCAClientFactorySPI Implementation and instantiates
+     * the provider's implementation.
+     * 
+     * @param properties    Properties that may be used when creating a new 
+     * instance of the SCAClient
+     * @param classLoader   ClassLoader that may be used when creating a new 
+     * instance of the SCAClient
+     * @param domainURI		URI for the Domain to which this client instance is connected
+     * @return new instance of the SCAClientFactory
+     * @throws ServiceRuntimeException Failed to create SCAClientFactory
+     * Implementation.
+     */
+    public SCAClientFactory find(Properties properties,
+                                 ClassLoader classLoader,
+                                 URI domainURI ) 
+    	throws NoSuchDomainException, ServiceRuntimeException {
+		if (classLoader == null) {
+			classLoader = getThreadContextClassLoader ();
+		}
+		final String factoryImplClassName =
+			discoverProviderFactoryImplClass(properties, classLoader);
+		final Class<? extends SCAClientFactory> factoryImplClass
+			= loadProviderFactoryClass(factoryImplClassName, 
+					                   classLoader);
+		final SCAClientFactory factory =
+			instantiateSCAClientFactoryClass(factoryImplClass,
+								   domainURI, properties );
+		return factory;
+	}
+    
+    /**
+     * Gets the Context ClassLoader for the current Thread.
+     * 
+     * @return The Context ClassLoader for the current Thread.
+     */
+    private static ClassLoader getThreadContextClassLoader () {
+        return AccessController.doPrivileged(
+                new PrivilegedAction<ClassLoader>() {
+             public ClassLoader run() {
+                 return Thread.currentThread().getContextClassLoader();
+             }
+         });
+    }
+
+    /**
+     * Attempts to discover the class name for the SCAClientFactorySPI
+     * implementation from the specified Properties, the System Properties
+     * or the specified ClassLoader.
+     * 
+     * @param properties    Properties that may be used when creating a new 
+     * instance of the SCAClient
+     * @param classLoader   ClassLoader that may be used when creating a new 
+     * instance of the SCAClient
+     * @return The class name of the SCAClientFactorySPI implementation
+     * @throw ServiceRuntimeException Failed to find implementation for 
+     * SCAClientFactorySPI.
+     */
+    private static String 
+        discoverProviderFactoryImplClass(Properties properties, 
+    		                             ClassLoader classLoader) 
+        throws ServiceRuntimeException {
+        String providerClassName = 
+        	checkPropertiesForSPIClassName(properties);
+        if (providerClassName != null) {
+            return providerClassName;
+        }
+
+        providerClassName = 
+        	checkPropertiesForSPIClassName(System.getProperties());
+        if (providerClassName != null) {
+            return providerClassName;
+        }
+        
+        providerClassName = checkMETAINFServicesForSPIClassName(classLoader);
+        if (providerClassName == null) {
+            throw new ServiceRuntimeException(
+            	"Failed to find implementation for SCAClientFactory");
+        }
+        
+        return providerClassName;
+    }
+    
+    /**
+     * Attempts to find the class name for the SCAClientFactorySPI 
+     * implementation from the specified Properties.
+     * 
+     * @param properties    Properties that may be used when creating a new 
+     * instance of the SCAClient
+     * @return The class name for the SCAClientFactorySPI implementation 
+     * or <code>null</code> if not found.
+     */
+    private static String 
+        checkPropertiesForSPIClassName(Properties properties) {
+        if (properties == null) {
+            return null;
+        }
+        
+        final String providerClassName = 
+        	properties.getProperty(SCA_CLIENT_FACTORY_PROVIDER_KEY);
+        if (providerClassName != null && providerClassName.length() > 0) {
+            return providerClassName;
+        }
+        
+        return null;
+    }
+
+    /**
+     * Attempts to find the class name for the SCAClientFactorySPI 
+     * implementation from the META-INF/services directory
+     * 
+     * @param cl   ClassLoader that may be used when creating a new 
+     * instance of the SCAClient
+     * @return The class name for the SCAClientFactorySPI implementation or
+     * <code>null</code> if not found.
+     */
+    private static String checkMETAINFServicesForSPIClassName(ClassLoader cl) 
+    {
+        final URL url = 
+        	cl.getResource(SCA_CLIENT_FACTORY_PROVIDER_META_INF_SERVICE);
+        if (url == null) {
+            return null;
+        }
+        
+        InputStream in = null; 
+        try {
+            in = url.openStream();
+            BufferedReader reader = null;
+            try {
+                reader = 
+                	new BufferedReader(new InputStreamReader(in, "UTF-8"));
+
+                String line;
+                while ((line = readNextLine(reader)) != null) {
+                    if (!line.startsWith("#") && line.length() > 0) {
+                        return line;
+                    }
+                }
+                
+                return null;
+            } finally {
+                closeStream(reader);
+            }
+        } catch (IOException ex) {
+            throw new ServiceRuntimeException(
+            		"Failed to discover SCAClientFactory provider", ex);
+        } finally {
+            closeStream(in);
+        }
+    }
+
+    /**
+     * Reads the next line from the reader and returns the trimmed version 
+     * of that line
+     * 
+     * @param reader The reader from which to read the next line
+     * @return The trimmed next line or <code>null</code> if the end of the 
+     * stream has been reached
+     * @throws IOException I/O error occurred while reading from Reader
+     */
+    private static String readNextLine(BufferedReader reader) 
+        throws IOException {
+    	
+        String line = reader.readLine();
+        if (line != null) {
+            line = line.trim();
+        }
+        return line;
+    }
+    
+    /**
+     * Loads the specified SCAClientFactory Implementation class.
+     * 
+     * @param factoryImplClassName The name of the SCAClientFactory 
+     * Implementation class to load
+     * @param classLoader   ClassLoader that may be used when creating a new 
+     * instance of the SCAClient
+     * @return The specified SCAClientFactory Implementation class
+     * @throws ServiceRuntimeException Failed to load the SCAClientFactory 
+     * Implementation class 
+     */
+    private static Class<? extends SCAClientFactory> 
+        loadProviderFactoryClass(String factoryImplClassName, 
+        		                 ClassLoader classLoader) 
+        throws ServiceRuntimeException {
+
+        try {
+            final Class<?> providerClass = 
+            	classLoader.loadClass(factoryImplClassName);
+            final Class<? extends SCAClientFactory> providerFactoryClass =
+                providerClass.asSubclass(SCAClientFactory.class);
+            return providerFactoryClass;
+        } catch (ClassNotFoundException ex) {
+            throw new ServiceRuntimeException(
+            	"Failed to load SCAClientFactory implementation class "
+            	+ factoryImplClassName, ex);
+        } catch (ClassCastException ex) {
+            throw new ServiceRuntimeException(
+            		"Loaded SCAClientFactory implementation class "
+            		+ factoryImplClassName
+                    + " is not a subclass of " 
+                    + SCAClientFactory.class.getName() , ex);
+        }
+    }
+
+    /**
+     * Instantiate an instance of the specified SCAClientFactorySPI 
+     * Implementation class.
+     *  
+     * @param factoryImplClass The SCAClientFactorySPI Implementation 
+     * class to instantiate.
+     * @param domainURI		URI for the Domain to which this client instance is connected
+     * @param properties    Properties that may be used when creating a new 
+     * instance of the SCAClient
+     * @return An instance of the SCAClientFactorySPI Implementation class
+     * @throws ServiceRuntimeException Failed to instantiate the specified 
+     * specified SCAClientFactorySPI Implementation class  
+     */
+    private static SCAClientFactory instantiateSCAClientFactoryClass(
+    			Class<? extends SCAClientFactory> factoryImplClass,
+        		URI domainURI, Properties properties)
+        throws NoSuchDomainException, ServiceRuntimeException {
+        
+        try {
+            Constructor<? extends SCAClientFactory> URIConstructor = 
+            	factoryImplClass.getConstructor(URI.class, Properties.class);
+            SCAClientFactory provider = 
+               URIConstructor.newInstance( domainURI, properties );
+            return provider;
+        } catch (Throwable ex) {
+            throw new ServiceRuntimeException(
+               "Failed to instantiate SCAClientFactory implementation class " 
+               + factoryImplClass, ex);
+        }
+    }
+    
+    /**
+     * Utility method for closing Closeable Object.
+     * 
+     * @param closeable The Object to close.
+     */
+    private static void closeStream(Closeable closeable) {
+        if (closeable != null) {
+            try{
+                closeable.close();
+            } catch (IOException ex) {
+                throw new ServiceRuntimeException("Failed to close stream", 
+                		                          ex);
+            }
+        }
+    }
+}