Tidy up and bug fixes

README.md

@@ -31,4 +31,52 @@ For additional client implementations in other languages, see:
 
 For more information, see [the nailgun website](https://github.com/facebook/nailgun).
 
+## Additional information
 
+### Example usage
+
+```bash
+$ ./nailgun-client/target/ng com.facebook.nailgun.examples.ThreadTest
+```
+
+### Logging
+
+To enable logging, start the server with `-Djava.util.logging.config.file="logging.properties"`. A relative file path is resolved in respect to the working directory
+(i.e. system property `user.dir`). An example file is at `nailgun-server/src/main/resources/logging.properties` but will only be used if (soft-) linked appropriate. 
+
+### Aliases
+
+* Aliases are loaded from `com/facebook/nailgun/builtins/builtins.properties`
+* Adding an alias example:
+  ```bash
+  $ ./nailgun-client/target/ng ng-alias test com.facebook.nailgun.examples.ThreadTest
+  $ ./nailgun-client/target/ng test
+  ```
+
+#### Built-in aliases
+
+```bash
+$ ./nailgun-client/target/ng ng-alias
+ng-alias        com.facebook.nailgun.builtins.NGAlias      
+                Displays and manages command aliases
+
+ng-cp           com.facebook.nailgun.builtins.NGClasspath  
+                Displays and manages the current system classpath
+
+ng-stats        com.facebook.nailgun.builtins.NGServerStats
+                Displays nail statistics
+
+ng-stop         com.facebook.nailgun.builtins.NGStop       
+                Shuts down the nailgun server
+
+ng-version      com.facebook.nailgun.builtins.NGVersion    
+                Displays the server version number.
+```
+
+The alias `ng-cp` is _very_ dangerous and YOU are encouraged to set 
+`com.facebook.nailgun.builtins.NGClasspath.ALLOW_CLASSPATH_MODIFICATION` to 
+`false`.
+
+### Links
+
+* [original homepage](http://www.martiansoftware.com/nailgun/)

logging.properties

@@ -0,0 +1 @@
+nailgun-server/src/main/resources/logging.properties

nailgun-examples/pom.xml

@@ -21,7 +21,7 @@
     <parent>
         <groupId>com.facebook</groupId>
         <artifactId>nailgun-all</artifactId>
-        <version>1.0.1</version>
+        <version>1.0.2-SNAPSHOT</version>
     </parent>
 
     <dependencies>

nailgun-examples/src/main/java/com/facebook/nailgun/examples/DumpAll.java

@@ -18,6 +18,8 @@
 package com.facebook.nailgun.examples;
 
 import com.facebook.nailgun.NGContext;
+
+import java.io.PrintStream;
 import java.util.TreeSet;
 
 /**
@@ -28,24 +30,26 @@
 public class DumpAll {
 
   public static void nailMain(NGContext context) {
-    context.out.println();
-    context.out.println("         context.getCommand(): " + context.getCommand());
-    context.out.println("     context.getInetAddress(): " + context.getInetAddress());
-    context.out.println("            context.getPort(): " + context.getPort());
-    context.out.println("context.getWorkingDirectory(): " + context.getWorkingDirectory());
-    context.out.println("   context.getFileSeparator(): " + context.getFileSeparator());
-    context.out.println("   context.getPathSeparator(): " + context.getPathSeparator());
-
-    context.out.println("\ncontext.getArgs():");
+    PrintStream out = context.getOut();
+    out.println();
+    out.println("         context.getCommand(): " + context.getCommand());
+    out.println("     context.getInetAddress(): " + context.getInetAddress());
+    out.println("            context.getPort(): " + context.getPort());
+    out.println("context.getWorkingDirectory(): " + context.getWorkingDirectory());
+    out.println("   context.getFileSeparator(): " + context.getFileSeparator());
+    out.println("   context.getPathSeparator(): " + context.getPathSeparator());
+
+    out.println("\ncontext.getArgs():");
     for (int i = 0; i < context.getArgs().length; ++i) {
-      context.out.println("   args[" + i + "]=" + context.getArgs()[i]);
+      out.println("   args[" + i + "]=" + context.getArgs()[i]);
     }
 
-    context.out.println("\ncontext.getEnv():");
+    out.println("\ncontext.getEnv():");
     TreeSet keys = new TreeSet(context.getEnv().keySet());
     for (Object okey : keys) {
       String key = (String) okey;
-      context.out.println("   env[\"" + key + "\"]=" + context.getEnv().getProperty(key));
+      out.println("   env[\"" + key + "\"]=" + context.getEnv().getProperty(key));
     }
+    out.flush();
   }
 }

nailgun-examples/src/main/java/com/facebook/nailgun/examples/Hash.java

@@ -83,16 +83,17 @@ public static void nailMain(NGContext context)
       // display available algorithms
       Set algs = getCryptoImpls("MessageDigest");
       for (Object alg : algs) {
-        context.out.println(alg);
+        context.getOut().println(alg);
       }
+      context.getOut().flush();
       return;
     }
 
     // perform the actual hash.  throw any exceptions back to the user.
     MessageDigest md = MessageDigest.getInstance(args[0]);
 
     byte[] b = new byte[1024];
-    int bytesRead = context.in.read(b);
+    int bytesRead = context.getIn().read(b);
     while (bytesRead != -1) {
       md.update(b, 0, bytesRead);
       bytesRead = System.in.read(b);
@@ -105,6 +106,7 @@ public static void nailMain(NGContext context)
       buf.append(HEXCHARS[(result[i] >> 4) & 0x0f]);
       buf.append(HEXCHARS[result[i] & 0x0f]);
     }
-    context.out.println(buf);
+    context.getOut().println(buf);
+    context.getOut().flush();
   }
 }

nailgun-examples/src/main/java/com/facebook/nailgun/examples/Heartbeat.java

@@ -47,7 +47,7 @@ public static void nailMain(final NGContext context) {
             }
           });
 
-      context.addHeartbeatListener(() -> context.out.print("H"));
+      context.addHeartbeatListener(() -> context.getOut().print("H"));
 
       synchronized (lock) {
         if (!shutdown.get()) {

nailgun-examples/src/main/java/com/facebook/nailgun/examples/Prompt.java

@@ -32,7 +32,8 @@ public static void nailMain(NGContext context) {
     if (result == null) {
       context.exit(1);
     } else {
-      context.out.println(result);
+      context.getOut().println(result);
+      context.getOut().flush();
     }
   }
 }

nailgun-examples/src/main/java/com/facebook/nailgun/examples/Stack.java

@@ -66,10 +66,11 @@ public static void nailMain(NGContext context) throws InterruptedException {
           sharedStack.wait();
         }
         if (sharedStack.size() > 0) {
-          context.out.println(sharedStack.pop());
+          context.getOut().println(sharedStack.pop());
           exitCode = 0;
         }
       }
+      context.getOut().flush();
       context.exit(exitCode);
       return;
     }

nailgun-server/pom.xml

@@ -21,7 +21,7 @@
     <parent>
         <groupId>com.facebook</groupId>
         <artifactId>nailgun-all</artifactId>
-        <version>1.0.1</version>
+        <version>1.0.2-SNAPSHOT</version>
     </parent>
 
     <dependencies>

nailgun-server/src/main/java/com/facebook/nailgun/AliasManager.java

@@ -35,14 +35,10 @@ public class AliasManager {
   private Map aliases;
 
   /** Creates a new AliasManager, populating it with default Aliases. */
-  public AliasManager() {
+  public AliasManager(ClassLoader cl) {
     aliases = new java.util.HashMap();
 
     Properties props = new Properties();
-    ClassLoader cl = getClass().getClassLoader();
-    if (cl == null)
-      cl = ClassLoader.getSystemClassLoader(); // needed if nailgun classes are loaded in the boot
-    // classpath.
     try (InputStream is =
         cl.getResourceAsStream("com/facebook/nailgun/builtins/builtins.properties")) {
       props.load(is);

nailgun-server/src/main/java/com/facebook/nailgun/NGClientListener.java

@@ -16,6 +16,7 @@
 
 package com.facebook.nailgun;
 
+@FunctionalInterface
 public interface NGClientListener {
 
   /**

nailgun-server/src/main/java/com/facebook/nailgun/NGCommunicator.java

@@ -17,7 +17,6 @@
 package com.facebook.nailgun;
 
 import java.io.ByteArrayInputStream;
-import java.io.Closeable;
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.EOFException;
@@ -48,7 +47,7 @@
  * using underlying socket streams. Also handles client disconnect events based on client
  * heartbeats.
  */
-public class NGCommunicator implements Closeable {
+public class NGCommunicator implements AutoCloseable {
 
   private static final Logger LOG = Logger.getLogger(NGCommunicator.class.getName());
   private final ExecutorService orchestratorExecutor;
@@ -383,6 +382,7 @@ private void stopOut() throws IOException {
     if (outClosed) {
       return;
     }
+    out.flush();
     outClosed = true;
 
     LOG.log(Level.FINE, "Shutting down socket for output");

nailgun-server/src/main/java/com/facebook/nailgun/NGConstants.java

@@ -17,8 +17,12 @@
 
 package com.facebook.nailgun;
 
+import java.io.File;
 import java.io.InputStream;
+import java.net.MalformedURLException;
+import java.net.URL;
 import java.util.Properties;
+import java.util.logging.Logger;
 
 /**
  * Just a simple holder for various NailGun-related contants.
@@ -27,6 +31,8 @@
  */
 public class NGConstants {
 
+  private static final Logger LOG = Logger.getLogger(NGConstants.class.getName());
+
   /** The default NailGun port (2113) */
   public static final int DEFAULT_PORT = 2113;
   /** The exit code sent to clients if nail completed successfully */
@@ -63,9 +69,6 @@ public class NGConstants {
   /** Chunk type marker for heartbeats sent to let the server know the client is still alive. */
   public static final byte CHUNKTYPE_HEARTBEAT = 'H';
 
-  /** Server version number */
-  public static final String VERSION = getVersion();
-
   /** Expected interval between heartbeats in milliseconds. */
   public static final short HEARTBEAT_INTERVAL_MILLIS = 1000;
 
@@ -78,17 +81,38 @@ public class NGConstants {
   /** Maximum chunk len sent from client. */
   public static final short MAXIMUM_CHUNK_LENGTH = 2048;
 
+  private static String VERSION = null;
+
   /** Loads the version number from a file generated by Maven. */
-  private static String getVersion() {
-    Properties props = new Properties();
-    try (InputStream is =
-        NGConstants.class.getResourceAsStream(
-            "/META-INF/maven/com.facebook/nailgun-server/pom.properties")) {
-      props.load(is);
-    } catch (Throwable e) {
-      // In static initialization context, outputting or logging an exception is dangerous
-      // It smells bad, but let's ignore it
+  public static String getVersion() throws MalformedURLException {
+    if (VERSION == null) {
+      Properties props = new Properties();
+      URL url =
+          NGServer.getInstance()
+              .getClassLoader()
+              .getResource("META-INF/maven/com.facebook/nailgun-server/pom.properties");
+      if (url == null) {
+        File file = new File("target/maven-archiver/pom.properties");
+        if (file.isFile()) {
+          url = file.toURI().toURL();
+        }
+      }
+      if (url == null) {
+        File file = new File("nailgun-server/target/maven-archiver/pom.properties");
+        if (file.isFile()) {
+          url = file.toURI().toURL();
+        }
+      }
+      LOG.info("get version info from " + url);
+      try (InputStream is = url.openStream()) {
+        props.load(is);
+      } catch (Throwable e) {
+        // In static initialization context, outputting or logging an exception is dangerous
+        // It smells bad, but let's ignore it
+      }
+      VERSION =
+          props.getProperty("version", System.getProperty("nailgun.server.version", "[UNKNOWN]"));
     }
-    return props.getProperty("version", System.getProperty("nailgun.server.version", "[UNKNOWN]"));
+    return VERSION;
   }
 }

nailgun-server/src/main/java/com/facebook/nailgun/NGContext.java

@@ -63,18 +63,22 @@ public class NGContext {
   private String workingDirectory = null;
 
   /** The client's stdin */
-  public InputStream in = null;
+  private InputStream in = null;
 
   /** The client's stdout */
-  public PrintStream out = null;
+  private PrintStream out = null;
 
   /** The client's stderr */
-  public PrintStream err = null;
+  private PrintStream err = null;
 
   private NGCommunicator communicator = null;
 
   /** Creates a new, empty NGContext */
-  public NGContext() {}
+  public NGContext(InputStream in, PrintStream out, PrintStream err) {
+    setIn(in);
+    setOut(out);
+    setErr(err);
+  }
 
   public void setCommunicator(NGCommunicator comm) {
     this.communicator = comm;
@@ -123,7 +127,7 @@ public String getWorkingDirectory() {
    * @param in The {@link InputStream} to use as stdin for the current nail. This should be an
    *     InputStream that ultimately reads from {@link NGInputStream}.
    */
-  public void setIn(InputStream in) {
+  private void setIn(InputStream in) {
     this.in = in;
     if (!(System.in instanceof ThreadLocalInputStream)) {
       throw new IllegalStateException("System.in should be set by nailgun.");
@@ -138,7 +142,7 @@ public void setIn(InputStream in) {
    * @param out The {@link PrintStream} to use as stdout for the current nail. This should be a
    *     PrintStream that ultimately writes to {@link NGOutputStream}.
    */
-  public void setOut(PrintStream out) {
+  private void setOut(PrintStream out) {
     this.out = out;
     if (!(System.out instanceof ThreadLocalPrintStream)) {
       throw new IllegalStateException("System.out should be set by nailgun.");
@@ -153,7 +157,7 @@ public void setOut(PrintStream out) {
    * @param err The {@link PrintStream} to use as stderr for the current nail. This should be a
    *     PrintStream that ultimately writes to {@link NGOutputStream}.
    */
-  public void setErr(PrintStream err) {
+  private void setErr(PrintStream err) {
     this.err = err;
     if (!(System.err instanceof ThreadLocalPrintStream)) {
       throw new IllegalStateException("System.err should be set by nailgun.");
@@ -162,6 +166,18 @@ public void setErr(PrintStream err) {
     tls.init(err);
   }
 
+  public InputStream getIn() {
+    return in;
+  }
+
+  public PrintStream getOut() {
+    return out;
+  }
+
+  public PrintStream getErr() {
+    return err;
+  }
+
   void setEnv(Properties remoteEnvironment) {
     this.remoteEnvironment = remoteEnvironment;
   }

nailgun-server/src/main/java/com/facebook/nailgun/NGHeartbeatListener.java

@@ -16,6 +16,7 @@
 
 package com.facebook.nailgun;
 
+@FunctionalInterface
 public interface NGHeartbeatListener {
 
   /**