working delete command

README.md

@@ -1,4 +1,4 @@
-# MiniDB
+<h1 align=center>MiniDB</h1>
 
 MiniDB is a type of [key-value](https://en.wikipedia.org/wiki/Key%E2%80%93value_database) like [XML Document Database](https://en.wikipedia.org/wiki/XML_database).
 
@@ -12,16 +12,22 @@ This is my college Project Submission for the following course
 - Course Code: IS4C04
 - Course Instructor: `Mr. Suhaas KP`, Assistant Professor, Department of Information Science and Engineering, `The National Institute Of Engineering`, Mysuru 570008
 
+### Made with
+- OpenJDK 16.0.1
+- Visual Studio Code
+- A bit Powered by [Github-Copilot-preview](https://copilot.github.com/)
+
 ## Usage
 
 Use the following commands to perform [CRUD](https://en.wikipedia.org/wiki/Create,_read,_update_and_delete) operations on this NoSQL Database.
 
 - `list` to list all the created databases
 - `new {name}` For creating a new database. (`{}` denotes that name is a variable)
-- `use {name}` to select the database from the existing ones for CRUD operations
+- `use {name}` to select the database from the existing ones for CRUD operations.
+- `delete {name}` to delete a database.
 - `schema {}` for declaring schema of the database. (NOTE: schema must be declared first to add any data)
-- `add {}` for adding data to the database. the data seperated with `,` must follow the schema.
-- `read` to read and show the data into the console.
+- `add {}` for adding data to the database. the data is seperated with `,` and must follow the schema.
+- `read` to read and show the data of the database.
 
 ### Example usage
 
@@ -41,4 +47,5 @@ schema id,name,legs
 add 1,cat,4
 add 2,fish,0
 ```
-Note: The first element is taken as the id, which is used as a pointer to data. So, it's a good practice to name it as `id` itself.
+
+Note: The first element is taken as the id, which is used as a pointer to data. So, it's a good practice to name it as `id` itself.

src/cli.java

@@ -117,11 +117,16 @@ private static void cliInputs(String input) {
                 break;
             }
 
-            case "update/delete": {
+            case "update": {
 
                 break;
             }
 
+            case "delete": {
+                registry.deleteDatabase(inputCmds[1]);
+                break;
+            }
+
             default: {
                 System.out.println("UNKNOWN COMMAND: " + inputCmds[0] + "\nType `info commands` for commands list");
                 break;

src/minidb/xmlParser/RegistryFile.java

@@ -1,5 +1,6 @@
 package minidb.xmlParser;
 
+import java.io.File;
 import java.time.LocalDateTime;
 import java.time.format.DateTimeFormatter;
 import java.util.Objects;
@@ -112,6 +113,7 @@ public void listAllDatabases() {
     public int checkDatabase(String name) {
         int x = -1;
         NodeList list = this.doc.getElementsByTagName("name");
+
         for (int i = 0; i < list.getLength(); i++) {
             Node dbNode = list.item(i);
             String dbName = dbNode.getTextContent();
@@ -149,6 +151,22 @@ public String getDatabasePath(String name, boolean create) {
     }
 
     public void deleteDatabase(String name) {
+        int dbid = checkDatabase(name);
+
+        if (dbid != -1) {
+            String dbPath = getDatabasePath(name, false);
+
+            NodeList list = this.doc.getElementsByTagName("database");
+            Element dbEntry = (Element) list.item(dbid);
+            dbEntry.getParentNode().removeChild(dbEntry);
+            this.updateFile();
 
+            File f = new File(dbPath);
+            f.delete();
+            print("Database deleted");
+
+        } else {
+            print("Database does not exist");
+        }
     }
 }