Update GenericWAC to implement ConfigurableWAC

GenericWebApplicationContext now implements
ConfigurableWebApplicationContext in order to be compatible with
Framework/DispatcherServlet and ContextLoader/Listener, especially with
regard to changes in SPR-7672 that allow for programmatic use of these
types within Servlet 3.0+ environments.  For the first time, it's now
reasonable to imagine injecting a GWAC into DispatcherServlet; the most
robust way to accommodate this possibility is for GWAC to implement
CWAC.

The implementation is in name only, allowing for interchangable use of
GWAC anywhere, for example, an XWAC could otherwise go.  Methods such
as setConfigLocation will throw UnsupportedOperationException if the
configLocation value actually contains text.  Other methods are
implemented as no-ops or to throw UOE as appropriate.

Issue: SPR-7672

org.springframework.web/src/main/java/org/springframework/web/context/support/GenericWebApplicationContext.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2009 the original author or authors.
+ * Copyright 2002-2011 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,6 +16,7 @@
 
 package org.springframework.web.context.support;
 
+import javax.servlet.ServletConfig;
 import javax.servlet.ServletContext;
 
 import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
@@ -27,16 +28,19 @@ import org.springframework.core.io.support.ResourcePatternResolver;
 import org.springframework.ui.context.Theme;
 import org.springframework.ui.context.ThemeSource;
 import org.springframework.ui.context.support.UiApplicationContextUtils;
+import org.springframework.util.ObjectUtils;
+import org.springframework.util.StringUtils;
+import org.springframework.web.context.ConfigurableWebApplicationContext;
 import org.springframework.web.context.ServletContextAware;
-import org.springframework.web.context.WebApplicationContext;
 
 /**
  * Subclass of {@link GenericApplicationContext}, suitable for web environments.
  *
- * <p>Implements the {@link WebApplicationContext} interface, but not
+ * <p>Implements the
  * {@link org.springframework.web.context.ConfigurableWebApplicationContext},
- * as it is not intended for declarative setup in <code>web.xml</code>. Instead,
+ * but is not intended for declarative setup in <code>web.xml</code>. Instead,
- * it is designed for programmatic setup, for example for building nested contexts.
+ * it is designed for programmatic setup, for example for building nested contexts or
+ * for use within Spring 3.1 {@link org.springframework.web.WebApplicationInitializer}s.
  *
  * <p><b>If you intend to implement a WebApplicationContext that reads bean definitions
  * from configuration files, consider deriving from AbstractRefreshableWebApplicationContext,
@@ -52,10 +56,11 @@ import org.springframework.web.context.WebApplicationContext;
  * this class detects a ThemeSource bean in the context, with the name "themeSource".
  *
  * @author Juergen Hoeller
+ * @author Chris Beams
  * @since 1.2
  */
 public class GenericWebApplicationContext extends GenericApplicationContext
-		implements WebApplicationContext, ThemeSource {
+		implements ConfigurableWebApplicationContext, ThemeSource {
 
 	private ServletContext servletContext;
 
@@ -179,4 +184,45 @@ public class GenericWebApplicationContext extends GenericApplicationContext
 		return this.themeSource.getTheme(themeName);
 	}
 
+
+	// ---------------------------------------------------------------------
+	// Pseudo-implementation of ConfigurableWebApplicationContext
+	// ---------------------------------------------------------------------
+
+	public void setServletConfig(ServletConfig servletConfig) {
+		// no-op
+	}
+
+	public ServletConfig getServletConfig() {
+		throw new UnsupportedOperationException();
+	}
+
+	public void setNamespace(String namespace) {
+		// no-op
+	}
+
+	public String getNamespace() {
+		throw new UnsupportedOperationException();
+	}
+
+	public void setConfigLocation(String configLocation) {
+		if (StringUtils.hasText(configLocation)) {
+			throw new UnsupportedOperationException(
+					"GenericWebApplicationContext does not support configLocation. Do " +
+					"you still have an 'contextConfigLocations' init-param set?");
+		}
+	}
+
+	public void setConfigLocations(String[] configLocations) {
+		if (!ObjectUtils.isEmpty(configLocations)) {
+			throw new UnsupportedOperationException(
+					"GenericWebApplicationContext does not support configLocations. Do " +
+					"you still have an 'contextConfigLocations' init-param set?");
+		}
+	}
+
+	public String[] getConfigLocations() {
+		throw new UnsupportedOperationException();
+	}
+
 }