Add SvlExample for juneau-svl demo

juneau-examples/juneau-examples-core/src/main/java/org/apache/juneau/examples/core/svl/SvlExample.java

@@ -0,0 +1,58 @@
+// ***************************************************************************************************************************
+// * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements.  See the NOTICE file *
+// * distributed with this work for additional information regarding copyright ownership.  The ASF licenses this file        *
+// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance            *
+// * with the License.  You may obtain a copy of the License at                                                              * 
+// *                                                                                                                         *
+// *  http://www.apache.org/licenses/LICENSE-2.0                                                                             *
+// *                                                                                                                         *
+// * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an  *
+// * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the License for the        *
+// * specific language governing permissions and limitations under the License.                                              *
+// ***************************************************************************************************************************
+package org.apache.juneau.examples.core.svl;
+
+import org.apache.juneau.svl.*;
+
+/**
+ * TODO
+ * 
+ */
+public class SvlExample {
+
+	/**
+	 * TODO
+	 * 
+	 * @param args
+	 */
+	public static void main(String[] args) {
+
+		VarResolver vr = VarResolver.DEFAULT;
+
+		// $E{key[,default]} for getting environment variables
+		System.out.println(vr.resolve("JAVA_HOME=$E{JAVA_HOME, not defined}"));
+
+		// $S{key[,default]} for getting system properties (uses System.getProperty() )
+		System.out.println(vr.resolve("os.name=$S{os.name, not defined}"));
+
+		// $IF{key[,default]} general if or if-else condition
+		// $NE{arg} will return true if not empty
+		System.out.println(vr.resolve("TEST_VAR is $IF{$NE{$E{TEST_VAR}}, not empty, empty}"));	
+
+		// $SW{arg,pattern1:then1[,pattern2:then2...]} switch-case
+		System.out.println(vr.resolve("$SW{Carrot, *Ap*:Fruit, *Car*:Veg, *:N/A}"));
+
+		// $PR{arg,pattern,replace} pattern replace
+		System.out.println(vr.resolve("Java version=$PR{$S{java.version}, (_([0-9]+)), \\ build=\\$2}"));
+
+		// $UC{arg} uppercase $LC{arg} lowecase
+		System.out.println(vr.resolve("$LC{JAVA_HOME} $UC{$E{JAVA_HOME}}"));
+
+		/*
+		 *  See all supported variable types at,
+		 *  http://juneau.apache.org/site/apidocs-7.2.1/overview-summary.html#juneau-svl
+		 *  NOTE - juneau-svl supports nested variables well
+		 * */
+	}
+
+}