Added the AbstractQuery class

src/main/java/de/gnmyt/sqltoolkit/querybuilder/AbstractQuery.java

@@ -0,0 +1,36 @@
+package de.gnmyt.sqltoolkit.querybuilder;
+
+import java.util.HashMap;
+
+public abstract class AbstractQuery {
+
+    private final HashMap<QueryParameter, Object> PARAMETERS = new HashMap<>();
+
+    /**
+     * The building logic of the sql query
+     *
+     * @return the sql query
+     */
+    public abstract SQLQuery build();
+
+    /**
+     * Adds a query parameter to the building list
+     *
+     * @param type  The type you want to use
+     * @param value The value of the type
+     */
+    public void addParameter(QueryParameter type, Object value) {
+        PARAMETERS.put(type, value);
+    }
+
+    /**
+     * Gets a query parameter from the building list
+     *
+     * @param type The type you want to get
+     * @return the query parameter
+     */
+    protected Object getParameter(QueryParameter type) {
+        return PARAMETERS.get(type);
+    }
+
+}