Check if a user is present in the local database or not

app/src/main/java/org/communiquons/android/comunic/client/data/DatabaseContract.java

@@ -19,7 +19,7 @@ public final class DatabaseContract {
     public static final String DATABASE_NAME = "database.db";
 
     /* Users info table */
-    public static abstract class UsersInfo implements BaseColumns {
+    public static abstract class UsersInfoSchema implements BaseColumns {
         public static final String TABLE_NAME = "users_info";
 
         public static final String COLUMN_NAME_USER_ID = "user_id";

app/src/main/java/org/communiquons/android/comunic/client/data/DatabaseHelper.java

@@ -4,7 +4,7 @@ import android.content.Context;
 import android.database.sqlite.SQLiteDatabase;
 import android.database.sqlite.SQLiteOpenHelper;
 
-import org.communiquons.android.comunic.client.data.DatabaseContract.UsersInfo;
+import org.communiquons.android.comunic.client.data.DatabaseContract.UsersInfoSchema;
 
 /**
  * Database helper. This file handles the creation / upgrade of the local database
@@ -26,16 +26,16 @@ public class DatabaseHelper extends SQLiteOpenHelper {
      * Creation and deletion of the users info table
      */
     private static final String SQL_CREATE_USERS_INFOS_TABLE =
-            "CREATE TABLE " + UsersInfo.TABLE_NAME + " (" +
+            "CREATE TABLE " + UsersInfoSchema.TABLE_NAME + " (" +
-                    UsersInfo._ID + " INTEGER PRIMARY KEY," +
+                    UsersInfoSchema._ID + " INTEGER PRIMARY KEY," +
-                    UsersInfo.COLUMN_NAME_USER_ID + INTEGER_TYPE + COMMA_SEP +
+                    UsersInfoSchema.COLUMN_NAME_USER_ID + INTEGER_TYPE + COMMA_SEP +
-                    UsersInfo.COLUMN_NAME_USER_FIRSTNAME + TEXT_TYPE + COMMA_SEP +
+                    UsersInfoSchema.COLUMN_NAME_USER_FIRSTNAME + TEXT_TYPE + COMMA_SEP +
-                    UsersInfo.COLUMN_NAME_USER_LASTNAME + TEXT_TYPE + COMMA_SEP +
+                    UsersInfoSchema.COLUMN_NAME_USER_LASTNAME + TEXT_TYPE + COMMA_SEP +
-                    UsersInfo.COLUMN_NAME_USER_ACCOUNT_IMAGE + TEXT_TYPE
+                    UsersInfoSchema.COLUMN_NAME_USER_ACCOUNT_IMAGE + TEXT_TYPE
             + " )";
 
     private static final String SQL_DELETE_USERS_INFOS_TABLE = "DROP TABLE IF EXISTS " +
-            UsersInfo.TABLE_NAME;
+            UsersInfoSchema.TABLE_NAME;
 
 
 

app/src/main/java/org/communiquons/android/comunic/client/data/UsersInfo/UserInfo.java

@@ -1,4 +1,4 @@
-package org.communiquons.android.comunic.client.data;
+package org.communiquons.android.comunic.client.data.UsersInfo;
 
 /**
  * This class contains the informations about a single user

app/src/main/java/org/communiquons/android/comunic/client/data/UsersInfo/UsersInfosDbHelper.java

@@ -0,0 +1,73 @@
+package org.communiquons.android.comunic.client.data.UsersInfo;
+
+import android.database.Cursor;
+import android.database.sqlite.SQLiteDatabase;
+
+import org.communiquons.android.comunic.client.data.DatabaseContract.UsersInfoSchema;
+import org.communiquons.android.comunic.client.data.DatabaseHelper;
+
+/**
+ * Users informations helpers
+ *
+ * Makes the interface between the UsersInfo object and the SQLite object
+ *
+ * @author Pierre HUBERT
+ * Created by pierre on 11/2/17.
+ */
+
+public class UsersInfosDbHelper {
+
+    /**
+     * Database helper
+     */
+    private DatabaseHelper dbHelper;
+
+    /**
+     * Class constructor
+     *
+     * @param dbHelper Database helper object
+     */
+    public UsersInfosDbHelper(DatabaseHelper dbHelper){
+        this.dbHelper = dbHelper;
+    }
+
+    /**
+     * Check wether a user is present in the database or not
+     *
+     * @param userID The user to research on the database
+     * @return boolean True if the user exists / false else
+     */
+    public boolean exists(int userID){
+
+        //Get the database
+        SQLiteDatabase db = dbHelper.getReadableDatabase();
+
+        //Define the condition of the research
+        String projection[] = {
+                UsersInfoSchema._ID
+        };
+
+        String selection = UsersInfoSchema.COLUMN_NAME_USER_ID + " = ?";
+        String[] selectionArgs = {""+userID};
+
+        String sortOrder = UsersInfoSchema._ID;
+
+        //Perform the request on the database
+        Cursor c = db.query(
+                UsersInfoSchema.TABLE_NAME,
+                projection,
+                selection,
+                selectionArgs,
+                null,
+                null,
+                sortOrder
+        );
+
+        int number_entries = c.getCount();
+
+        //Close cursor
+        c.close();
+
+        return number_entries > 0;
+    }
+}