+ improvements to the Gemfire sample

SGF-3

samples/hello-world/src/main/java/org/springframework/data/gemfire/samples/helloworld/CommandProcessor.java

@@ -16,13 +16,18 @@
 
 package org.springframework.data.gemfire.samples.helloworld;
 
+import java.io.BufferedInputStream;
 import java.io.BufferedReader;
 import java.io.IOException;
+import java.io.InputStream;
 import java.io.InputStreamReader;
+import java.util.Scanner;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
+import com.gemstone.gemfire.cache.Region;
+
 /**
  * @author Costin Leau
  */
@@ -30,33 +35,47 @@ public class CommandProcessor {
 
 	private static final Log log = LogFactory.getLog(CommandProcessor.class);
 
+	private static String help = initHelp();
+	private static String EMPTY = "";
+
 	boolean threadActive;
 	private Thread thread;
 
+	private Region<String, String> region;
+
+	public CommandProcessor(Region<String, String> region) {
+		this.region = region;
+	}
+
 	void start() {
 		if (thread == null) {
-			threadActive = false;
+			threadActive = true;
 			thread = new Thread(new Task(), "cmd-processor");
 			thread.start();
 		}
 	}
 
 	void stop() throws Exception {
-		threadActive = true;
-		thread.join(3 * 1000);
+		threadActive = false;
+		thread.join();
+	}
+
+	void awaitCommands() throws Exception {
+		thread.join();
 	}
 
 	private class Task implements Runnable {
 
 		public void run() {
+			System.out.println("Hello World!");
+			System.out.println("Want to interact with the world ? ...");
+			System.out.println(help);
 			try {
-
 				BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
 
 				while (threadActive) {
 					if (br.ready()) {
-						String line = br.readLine();
-						log.info("Read line " + line);
+						process(br.readLine());
 					}
 				}
 			} catch (IOException ioe) {
@@ -65,4 +84,74 @@ public class CommandProcessor {
 			}
 		}
 	}
-}
+
+	private static String initHelp() {
+		try {
+			InputStream stream = CommandProcessor.class.getResourceAsStream("help.txt");
+			byte[] buffer = new byte[stream.available() > 0 ? stream.available() : 300];
+
+			BufferedInputStream bf = new BufferedInputStream(stream);
+			bf.read(buffer);
+			return new String(buffer);
+		} catch (IOException io) {
+			throw new IllegalStateException("Cannot read help file");
+		}
+	}
+
+	String process(String line) throws Exception {
+		Scanner sc = new Scanner(line);
+		String command = sc.next();
+
+		// parse commands w/o arguments
+		if ("exit".equalsIgnoreCase(command)) {
+			threadActive = false;
+			return EMPTY;
+		}
+		if ("help".equalsIgnoreCase(command)) {
+			return help;
+		}
+		if ("size".equalsIgnoreCase(command)) {
+			return EMPTY + region.size();
+		}
+		if ("clear".equalsIgnoreCase(command)) {
+			region.clear();
+			return EMPTY;
+		}
+		if ("keys".equalsIgnoreCase(command)) {
+			return region.keySet().toString();
+		}
+		if ("values".equalsIgnoreCase(command)) {
+			return region.values().toString();
+		}
+
+		String arg = sc.next();
+
+		// commands w/ 1 arg
+		if ("containsKey".equalsIgnoreCase(command)) {
+			return EMPTY + region.containsKey(arg);
+		}
+		if ("containsValue".equalsIgnoreCase(command)) {
+			return EMPTY + region.containsValue(arg);
+		}
+		if ("query".equalsIgnoreCase(command)) {
+			return region.query(command).toString();
+		}
+		if ("get".equalsIgnoreCase(command)) {
+			return region.get(arg);
+		}
+		if ("remove".equalsIgnoreCase(command)) {
+			return region.remove(arg);
+		}
+
+		// commands w/ 2 args
+
+		String arg2 = sc.next();
+
+		if ("put".equalsIgnoreCase(command)) {
+			return region.put(arg, arg2);
+		}
+
+		sc.close();
+		return "unknown command - run 'help' for available commands";
+	}
+}

samples/hello-world/src/main/java/org/springframework/data/gemfire/samples/helloworld/HelloWorld.java

@@ -39,7 +39,7 @@ public class HelloWorld {
 	private static final Log log = LogFactory.getLog(HelloWorld.class);
 
 	// inject the region
-	@Resource
+	@Resource(name = "hw-region")
 	private Region<String, String> region;
 
 	// re-inject the region (as a Map)
@@ -54,7 +54,7 @@ public class HelloWorld {
 	void start() {
 		log.info("Member " + region.getCache().getDistributedSystem().getDistributedMember().getId()
 				+ " connecting to region [" + region.getName() + "]");
-		processor = new CommandProcessor();
+		processor = new CommandProcessor(region);
 		processor.start();
 	}
 
@@ -64,4 +64,12 @@ public class HelloWorld {
 				+ " disconnecting from region [" + region.getName() + "]");
 		processor.stop();
 	}
+
+	public void greetWorld() {
+		try {
+			processor.awaitCommands();
+		} catch (Exception ex) {
+			throw new IllegalStateException("Cannot greet world", ex);
+		}
+	}
 }

samples/hello-world/src/main/java/org/springframework/data/gemfire/samples/helloworld/Main.java

@@ -45,5 +45,9 @@ public class Main {
 		AbstractApplicationContext ctx = new ClassPathXmlApplicationContext(res);
 		// shutdown the context along with the VM
 		ctx.registerShutdownHook();
+
+		// call greet world to prevent the thread from ending
+		HelloWorld bean = ctx.getBean(HelloWorld.class);
+		bean.greetWorld();
 	}
 }

samples/hello-world/src/main/resources/org/springframework/data/gemfire/samples/helloworld/help.txt

@@ -0,0 +1,16 @@
+Supported commands are:
+
+get <key> - retrieves an entry (by key) from the grid
+put <key> <value> - puts a new entry into the grid
+remove <key> - removes an entry (by key) from the grid
+size - returns the size of the grid
+clear - removes all mapping in the grid
+keys - returns the keys contained by the grid
+values - returns the values contained by the grid
+containsKey <key> - indicates if the given key is contained by the grid
+containsValue <value> - indicates if the given value is contained by the grid
+
+query <query> - executes a query on the grid
+
+help - this info
+exit - this node exists