pmd: CLI - make sure we display the usage help text

Therefore make the -h option a help option.
Make the auxclasspath option description look nicer - newlines break the layout.
Always display the jcommander usage help text.
And exit with an error code in case there are parameter errors.

pmd/src/main/java/net/sourceforge/pmd/PMD.java

@@ -335,8 +335,6 @@ public class PMD {
 		return languages;
 	}
 
-	private static final int ERROR_STATUS = 1;
-
     /**
      * Entry to invoke PMD as command line tool
      *
@@ -367,7 +365,7 @@ public class PMD {
 		} catch (Exception e) {
 			PMDCommandLineInterface.buildUsageText();
 			System.out.println(e.getMessage());
-			status = ERROR_STATUS;
+			status = PMDCommandLineInterface.ERROR_STATUS;
 		} finally {
 		    logHandlerManager.close();
 		    LOG.setLevel(oldLogLevel);

pmd/src/main/java/net/sourceforge/pmd/cli/PMDCommandLineInterface.java

@@ -27,17 +27,24 @@ public class PMDCommandLineInterface {
 	public static final String NO_EXIT_AFTER_RUN = "net.sourceforge.pmd.cli.noExit";
 	public static final String STATUS_CODE_PROPERTY = "net.sourceforge.pmd.cli.status";
 
+	public static final int ERROR_STATUS = 1;
+
 	public static PMDParameters extractParameters(PMDParameters arguments, String[] args, String progName) {
+		jcommander = new JCommander(arguments);
+		jcommander.setProgramName(progName);
+
 		try {
-			jcommander = new JCommander(arguments, args);
-			jcommander.setProgramName(progName);
+			jcommander.parse(args);
 			if (arguments.isHelp()) {
 				jcommander.usage();
-				System.exit(0);
+				System.out.println(buildUsageText());
+				setStatusCodeOrExit(0);
 			}
 		} catch (ParameterException e) {
+			jcommander.usage();
 			System.out.println(buildUsageText());
 			System.out.println(e.getMessage());
+			setStatusCodeOrExit(ERROR_STATUS);
 		}
 		return arguments;
 	}
@@ -61,7 +68,7 @@ public class PMDCommandLineInterface {
 		+ "3) A ruleset filename or a comma-delimited string of ruleset filenames"				+ PMD.EOL
 		+ PMD.EOL
 		+ "For example: "																		+ PMD.EOL
-		+ "c:\\> " + launchCmd + "-d c:\\my\\source\\code -f html -R java-unusedcode"					+ PMD.EOL
+		+ "c:\\> " + launchCmd + " -d c:\\my\\source\\code -f html -R java-unusedcode"			+ PMD.EOL
 		+ PMD.EOL;
 
 		fullText += supportedVersions() + PMD.EOL;
@@ -148,12 +155,16 @@ public class PMDCommandLineInterface {
 	}
 
 	public static void run(String[] args) {
-    	if ( isExitAfterRunSet() )
-    		System.exit(PMD.run(args));
-    	else
-    		setStatusCode(PMD.run(args));
+		setStatusCodeOrExit(PMD.run(args));
     }
 
+	public static void setStatusCodeOrExit(int status) {
+		if ( isExitAfterRunSet() )
+			System.exit(status);
+		else
+			setStatusCode(status);
+	}
+
     private static boolean isExitAfterRunSet() {
     	return (System.getenv(NO_EXIT_AFTER_RUN) == null ? false : true);
     }

pmd/src/main/java/net/sourceforge/pmd/cli/PMDParameters.java

@@ -28,7 +28,7 @@ public class PMDParameters {
 	@Parameter(names = {"-debug", "-verbose", "-D", "-V"}, description = "Debug mode")
 	private boolean debug = false;
 	
-	@Parameter(names = {"-help","-h","-H"}, description = "Display help on usage")
+	@Parameter(names = {"-help","-h","-H"}, description = "Display help on usage", help = true)
 	private boolean help = false;
 
 	@Parameter(names= {"-encoding", "-e"} , description = "specifies the character set encoding of the source code files PMD is reading (i.e., UTF-8)")
@@ -67,7 +67,7 @@ public class PMDParameters {
 	@Parameter(names = {"-language", "-l"}, description = "specify version of a language PMD should use")
 	private String language = Language.getDefaultLanguage().getTerseName();
 
-	@Parameter(names = "-auxclasspath", description = "specifies the classpath for libraries used by the source code (used by type resolution)\n(alternatively, a 'file://' URL to a text file containing path elements on consecutive lines")
+	@Parameter(names = "-auxclasspath", description = "specifies the classpath for libraries used by the source code. This is used by the type resolution. Alternatively, a 'file://' URL to a text file containing path elements on consecutive lines can be specified.")
 	private String auxclasspath;	
 	
 	class PropertyConverter implements IStringConverter<Properties> {