Update Delete command UG, DG and messages

docs/UserGuide.md

@@ -187,18 +187,19 @@ Examples:
 
 _{To be updated...}_
 
-Deletes the specified contact from the address book.
+Deletes the specified contact from the address book and its associated contacts if specified.
+Format: `delete INDEX [--recursive]` or `delete --id ID [--recursive]`
 
-Format: `delete INDEX`
+* `INDEX` refers to the index number shown on the list and must be a positive integer.
+* Deletes the person with id `ID` if specified, ignoring if the contact is shown in the list.
+* Deletes other contacts associated under the selected contact if `--recursive` is used, ignoring if the contact is shown in the list.
 
+Examples:
+* `delete 1` deletes the 1st contact in the list of contacts shown.
+* `delete --id 045f` deletes the contact with id `045f` in the address book.
+* `delete 1 --recursive` deletes the 1st contact along with other contacts associated under it.
 
-* Deletes the contact at the specified `INDEX`.
-* The index refers to the index number shown in the displayed contact list.
-* The index **must be a positive integer** 1, 2, 3, ...
 
-Examples:
-* `list` followed by `delete 2` deletes the 2nd contact in the address book.
-* `find Betsy` followed by `delete 1` deletes the 1st contact in the results of the `find` command.
 
 
 ### Clearing all entries: `clear`
@@ -251,7 +252,7 @@ Action | Format, Examples
 **Add Organization** | `add --type o[rganization] --name <NAME> [--id ID] [--phone NUMBER] [--email EMAIL] [--url URL] [--addr ADDRESS] [--stat STATUS] [--pos POSITION] [--tag TAG]...`<br> e.g., `add --type o --name NUS --phone 0123456789 --email example@nus.edu.sg --url https://www.nus.edu.sg/ --stat pending --pos Research`
 **Add Recruiter** | `add --type r[ecruiter] --name <NAME> [--id ID] [--oid ORG_ID] [--phone NUMBER] [--email EMAIL] [--url URL] [--addr ADDRESS] [--tag TAG]...`<br> e.g., `add --name John Doe --type Recruiter --oid paypal-sg`
 **Clear** | `clear`
-**Delete** | `delete INDEX`<br> e.g., `delete 3`
+**Delete** | `delete INDEX [--recursive]` or <br> `delete --id ID [--recursive]` <br> e.g., `delete 3`, `delete --id 55tg`
 **Edit** | Coming soon...
 **Find** | `find KEYWORD [MORE_KEYWORDS]`<br> e.g., `find James Jake`
 **List** | `list`

src/main/java/seedu/address/logic/commands/DeleteCommand.java

@@ -1,6 +1,8 @@
 package seedu.address.logic.commands;
 
 import static java.util.Objects.requireNonNull;
+import static seedu.address.logic.parser.CliSyntax.FLAG_ID;
+import static seedu.address.logic.parser.CliSyntax.FLAG_RECURSIVE;
 
 import java.util.List;
 import java.util.function.Function;
@@ -22,8 +24,14 @@ public class DeleteCommand extends Command {
 
     public static final String MESSAGE_USAGE = COMMAND_WORD
             + ": Deletes the contact identified by the index number used in the displayed contact list.\n"
-            + "Parameters: INDEX (must be a positive integer)\n"
-            + "Example: " + COMMAND_WORD + " 1";
+            + "Parameters: "
+            + "INDEX (must be a positive integer) "
+            + FLAG_ID + " ID "
+            + FLAG_RECURSIVE + " RECURSIVE "
+            + "\n"
+            + "Example 1: " + COMMAND_WORD + " 1\n"
+            + "Example 2: " + COMMAND_WORD + " --id 0d0h4\n"
+            + "Example 3: " + COMMAND_WORD + " 1 --recursive\n";
 
     public static final String MESSAGE_DELETE_CONTACT_SUCCESS = "Deleted Contact: %1$s";