add DbConnect and DbAdapter#getByUrl

appmate/src/main/java/nctu/fintech/appmate/DbAdapter.java

@@ -23,6 +23,7 @@
 /**
  * SQL connect, client side
  *
+ * <p>
  * Implemented features:
  * <ol>
  *     <li>Get: get all</li>
@@ -32,6 +33,7 @@
  *     <li>Update: update specific item by index</li>
  *     <li>Delete: delete specific item by index</li>
  * </ol>
+ * </p>
  *
  * @version 0.9.2 (2016-09-14)
  * @author  Tzu-ting, NCTU Fintech Center
@@ -252,6 +254,25 @@ public boolean delete(int index) {
         }
     }
 
+    /**
+     * get object by URL
+     * <p>
+     * <strong>NOTICE</strong>
+     * This method currently run WITHOUT any anti-foolish procedure. Please DO NOT use this
+     *
+     * @param url request url
+     * @return retrieved object, or null when connection failed
+     */
+    public JSONObject getByUrl(String url) {
+        try {
+            String response = sendRequest("GET", url, HttpURLConnection.HTTP_OK, true);
+            return new JSONObject(response);
+        } catch (Exception e) {
+            Log.e(this.getClass().getName(), e.getMessage());
+            return null;
+        }
+    }
+
     //*******************************************************
     //  Internal members
     //

appmate/src/main/java/nctu/fintech/appmate/DbConnection.java

@@ -0,0 +1,64 @@
+package nctu.fintech.appmate;
+
+import android.support.annotation.NonNull;
+
+import java.lang.*;
+
+/**
+ * Handle the connect to the database.
+ * <p>This class helps to handle host domain and authentication to prevent rookie mistake.</p>
+ *<p>usage example:
+ * {@code
+ *        DbConnection connection = new DbConnection("localhost:8000", "USER", "PASSW0RD");
+ *        DbAdapter tableAdapter = connection.getTable("table_name");
+ * } </p>
+ * @version 1.0 (2016-9-22)
+ * @author Tzu-ting, NCTU Fintech Center
+ */
+public class DbConnection {
+
+    private final String _host;
+
+    private final boolean _useAuth;
+    private String _username = null;
+    private String _password = null;
+
+    /**
+     * Create a connection to the database which does NOT require authentication
+     *
+     * @param host host domain where database located
+     */
+    public DbConnection(@NonNull String host) {
+        _host = host;
+        _useAuth = false;
+    }
+
+    /**
+     * Create a connection to the database which requires authentication.
+     *
+     * @param host     host domain where database located
+     * @param username username/id to login
+     * @param password password to login
+     */
+    public DbConnection(@NonNull String host, @NonNull String username, @NonNull String password) {
+        _host = host;
+        _useAuth = true;
+        _username = username;
+        _password = password;
+    }
+
+    /**
+     * Get {@code DbAdapter} for specific table
+     *
+     * @param tableName table name to retrieve
+     * @return a {@code DbAdapter} linked to the specific table
+     */
+    public DbAdapter getTable(@NonNull String tableName) {
+        if (_useAuth) {
+            return new DbAdapter(_host, tableName, _username, _password);
+        } else {
+            return new DbAdapter(_host, tableName);
+        }
+    }
+
+}