Added validity check for commands

client/src/main/java/envoy/client/data/commands/SystemCommandsMap.java

@@ -3,6 +3,7 @@ package envoy.client.data.commands;
 import java.util.*;
 import java.util.function.Function;
 import java.util.logging.Level;
+import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 
 import envoy.util.EnvoyLog;
@@ -23,45 +24,58 @@ public class SystemCommandsMap {
 
 	private final HashMap<String, SystemCommand> systemCommands = new HashMap<>();
 
+	private final Pattern commandBounds = Pattern.compile("^[a-zA-Z0-9_:!\\(\\)\\?\\.\\,\\;\\-]+$");
+
 	/**
+	 * Adds a command with according action and the number of arguments that should
+	 * be parsed if the command does not violate API constrictions to the map.
+	 *
 	 * @param command           the string that must be inputted to execute the
 	 *                          given action
 	 * @param action            the action that should be performed
 	 * @param numberOfArguments the amount of arguments that need to be parsed for
 	 *                          the underlying function
+	 * @see SystemCommandsMap#isValidKey(String)
 	 * @since Envoy Client v0.1-beta
 	 */
 	public void addCommand(String command, Function<String[], Void> action, int numberOfArguments) {
-		systemCommands.put(command, new SystemCommand(action, numberOfArguments, ""));
+		if (isValidKey(command)) systemCommands.put(command, new SystemCommand(action, numberOfArguments, ""));
 	}
 
 	/**
+	 * Adds a command with according action, the number of arguments that should be
+	 * parsed and a description of the system command, if the command does not
+	 * violate API constrictions, to the map.
+	 *
 	 * @param command           the string that must be inputted to execute the
 	 *                          given action
 	 * @param action            the action that should be performed
 	 * @param numberOfArguments the amount of arguments that need to be parsed for
 	 *                          the underlying function
 	 * @param description       the description of this {@link SystemCommand}
+	 * @see SystemCommandsMap#isValidKey(String)
 	 * @since Envoy Client v0.1-beta
 	 */
 	public void addCommand(String command, Function<String[], Void> action, int numberOfArguments, String description) {
-		systemCommands.put(command, new SystemCommand(action, numberOfArguments, description));
+		if (isValidKey(command)) systemCommands.put(command, new SystemCommand(action, numberOfArguments, description));
 	}
 
 	/**
-	 * Adds a new {@link SystemCommand} to the map that does not depend upon
+	 * Adds a command with according action that does not depend on arguments, if
-	 * arguments in the given String
+	 * the command does not violate API constrictions, to the map.
 	 *
 	 * @param command the string that must be inputted to execute the given action
 	 * @param action  the action that should be performed. To see why this Function
 	 *                takes a {@code String[]}, see {@link SystemCommand}
+	 * @see SystemCommandsMap#isValidKey(String)
 	 * @since Envoy Client v0.1-beta
 	 */
 	public void addNoArgCommand(String command, Function<String[], Void> action) { addCommand(command, action, 0); }
 
 	/**
-	 * Adds a new {@link SystemCommand} to the map that does not depend upon
+	 * Adds a command with according action that does not depend on arguments and a
-	 * arguments in the given String
+	 * description of that action, if the command does not violate API
+	 * constrictions, to the map.
 	 *
 	 * @param command     the string that must be inputted to execute the given
 	 *                    action
@@ -69,11 +83,18 @@ public class SystemCommandsMap {
 	 *                    Function takes a {@code String[]}, see
 	 *                    {@link SystemCommand}
 	 * @param description the description of this {@link SystemCommand}
+	 * @see SystemCommandsMap#isValidKey(String)
 	 * @since Envoy Client v0.1-beta
 	 */
 	public void addNoArgCommand(String command, Function<String[], Void> action, String description) { addCommand(command, action, 0); }
 
 	/**
+	 * Convenience method that does the same as
+	 * {@link SystemCommandsMap#addCommand(String, Function, int)}.
+	 * <p>
+	 * Adds a command with according action and the number of arguments that should
+	 * be parsed if the command does not violate API constrictions to the map.
+	 *
 	 * @param command           the string that must be inputted to execute the
 	 *                          given action
 	 * @param action            the action that should be performed. To see why this
@@ -81,10 +102,32 @@ public class SystemCommandsMap {
 	 *                          {@link SystemCommand}
 	 * @param numberOfArguments the amount of arguments that need to be parsed for
 	 *                          the underlying function
+	 * @see SystemCommandsMap#isValidKey(String)
 	 * @since Envoy Client v0.1-beta
 	 */
-	public void add(String command, Function<String[], Void> action, int numberOfArguments) {
+	public void add(String command, Function<String[], Void> action, int numberOfArguments) { addCommand(command, action, numberOfArguments); }
-		systemCommands.put(command, new SystemCommand(action, numberOfArguments, ""));
+
+	/**
+	 * Examines whether a key can be put in the map and logs it with
+	 * {@code Level.WARNING} if that key violates API constrictions <br>
+	 * (allowed chars are <b>a-zA-Z0-9_:!()?.,;-</b>)
+	 * <p>
+	 * The approach to not throw an exception was taken so that an ugly try-catch
+	 * block for every addition to the system commands map could be avoided, an
+	 * error that
+	 * should only occur during implementation and not in production.
+	 *
+	 * @param command the key to examine
+	 * @return whether this key can be used in the map
+	 * @since Envoy Client v0.1-beta
+	 */
+	public final boolean isValidKey(String command) {
+		final boolean valid = commandBounds.matcher(command).matches();
+		if (!valid) EnvoyLog.getLogger(SystemCommandsMap.class)
+			.log(Level.WARNING,
+					"The command \"" + command + "\" is not valid. It will cause problems in execution: Only the characters " + commandBounds
+							+ "are allowed");
+		return valid;
 	}
 
 	/**